0001564590-21-008833 | 10-K | XBRL Viewer | Dynavax Technologies Corp

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Document and Entity Information - USD ($) $ in Millions	12 Months Ended
Document and Entity Information - USD ($) $ in Millions	Dec. 31, 2020	Feb. 22, 2021	Jun. 30, 2020
Cover [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2020
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	FY
Trading Symbol	DVAX
Entity Registrant Name	Dynavax Technologies Corp
Entity Central Index Key	0001029142
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	Yes
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		113,256,101
Entity Public Float			$ 884.4
Title of 12(b) Security	Common Stock, $0.001 par value
Security Exchange Name	NASDAQ
Entity File Number	001-34207
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	33-0728374
Entity Address, Address Line One	2100 Powell Street
Entity Address, Address Line Two	Suite 900
Entity Address, City or Town	Emeryville
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	94608
City Area Code	510
Local Phone Number	848-5100
Document Annual Report	true
Document Transition Report	false
Entity Interactive Data Current	Yes
ICFR Auditor Attestation Flag	true
Documents Incorporated by Reference	Portions of the Definitive Proxy Statement for the registrant’s 2021 Annual Meeting of Stockholders are incorporated by reference into Part III, Items 10-14 of this Form 10-K. The Definitive Proxy Statement will be filed no later than 120 days after the close of the registrant’s fiscal year ended December 31, 2020.

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 32,073	$ 39,884
Marketable securities available-for-sale	132,963	111,171
Accounts and other receivables, net	22,661	8,886
Inventories, net	63,689	41,332
Prepaid manufacturing	29,423
Prepaid expenses and other current assets	9,206	7,380
Total current assets	290,015	208,653
Property and equipment, net	30,567	32,022
Intangible assets, net		2,500
Operating lease right-of-use assets	26,583	30,252
Goodwill	2,297	2,081
Restricted cash	237	216
Other assets	3,573	3,344
Total assets	353,272	279,068
Current liabilities:
Accounts payable	3,312	9,278
Accrued research and development	2,805	4,120
Accrued liabilities	19,099	14,802
Warrant liability	10,736	14,860
Deferred revenue	38,212
Other current liabilities	3,247	9,987
Total current liabilities	77,411	53,047
Long-term debt, net of debt discount of $1,094 and $1,394 at December 31, 2020 and 2019, respectively	179,811	178,601
Long-term portion of lease liabilities	34,789	37,845
Other long-term liabilities	2,568	1,285
Total liabilities	294,579	270,778
Commitments and contingencies (Note 9)
Stockholders’ equity:
Preferred stock value
Common stock: $0.001 par value; 278,000 shares and 139,000 shares authorized at December 31, 2020 and 2019, respectively; 110,190 shares and 83,871 shares issued and outstanding at December 31, 2020 and 2019, respectively	110	84
Additional paid-in capital	1,352,374	1,229,417
Accumulated other comprehensive gain (loss)	273	(2,387)
Accumulated deficit	(1,294,064)	(1,218,824)
Total stockholders’ equity	58,693	8,290
Total liabilities and stockholders’ equity	353,272	279,068
Series B Convertible Preferred Stock
Stockholders’ equity:
Preferred stock value

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Long-term debt, net of debt discount	$ 1,094	$ 1,394
Preferred stock, par value	$ 0.001	$ 0.001
Preferred stock, shares authorized	5,000,000	5,000,000
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	278,000,000	139,000,000
Common stock, shares issued	110,190,000	83,871,000
Common stock, shares outstanding	110,189,859	83,871,000
Series B Convertible Preferred Stock
Preferred stock, shares issued	4,000	5,000
Preferred stock, shares outstanding	4,140	5,000

Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Revenues:
Total revenues	$ 46,551	$ 35,219	$ 8,198
Operating expenses:
Cost of sales - amortization of intangible assets	2,500	9,217	10,862
Research and development	28,607	62,331	74,951
Selling, general and administrative	79,256	74,986	64,770
Restructuring		13,356
Total operating expenses	114,922	170,062	161,517
Gain on sale of assets	(6,851)
Loss from operations	(68,371)	(134,843)	(153,319)
Other income (expense):
Interest income	1,260	3,370	3,828
Interest expense	(19,062)	(16,977)	(9,338)
Sublease income	7,706	2,619
Change in fair value of warrant liability (Note 14)	4,124	(7,500)
Other	(897)	731	(70)
Net loss	(75,240)	(152,600)	(158,899)
Preferred stock deemed dividend		(3,267)
Net loss allocable to common stockholders	$ (75,240)	$ (155,867)	$ (158,899)
Basic net loss per share allocable to common stockholders	$ (0.75)	$ (2.16)	$ (2.55)
Weighted average shares used to compute basic net loss per share allocable to common stockholders	100,753	72,024	62,362
Diluted net loss per share allocable to common stockholders	$ (0.78)	$ (2.16)	$ (2.55)
Weighted average shares used to compute diluted net loss per share allocable to common stockholders	101,504	72,024	62,362
Product
Revenues:
Total revenues	$ 39,307	$ 34,644	$ 6,812
Operating expenses:
Cost of sales - product	11,410	10,172	10,934
Cost of sales - amortization of intangible assets	2,500	9,217	10,862
Other Revenue
Revenues:
Total revenues	$ 7,244	$ 575	$ 1,386

Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Statement Of Income And Comprehensive Income [Abstract]
Net loss	$ (75,240)	$ (152,600)	$ (158,899)
Other comprehensive income (loss), net of tax:
Reclassification of realized gain on available-for-sale securities recognized in interest income	(21)
Change in unrealized gain (loss) on marketable securities available-for-sale	(20)	140	12
Cumulative foreign currency translation adjustments	2,701	(512)	(1,146)
Total other comprehensive income (loss)	2,660	(372)	(1,134)
Total comprehensive loss	$ (72,580)	$ (152,972)	$ (160,033)

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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+ Details

- Definition

Amount after tax and reclassification adjustments of other comprehensive income (loss).

+ References

+ Details

Consolidated Statements of Stockholders' Equity - USD ($) shares in Thousands, $ in Thousands	Total	Offering	Offering Series B Convertible Preferred Stock	Common Stock	Common Stock Offering	Preferred Stock	Preferred Stock Offering Series B Convertible Preferred Stock	Additional Paid-in Capital	Additional Paid-in Capital Offering	Additional Paid-in Capital Offering Series B Convertible Preferred Stock	Accumulated Other Comprehensive (Loss) Income	Accumulated Deficit
Beginning Balances at Dec. 31, 2017	$ 199,549			$ 62				$ 1,107,693			$ (881)	$ (907,325)
Beginning Balances (in shares) at Dec. 31, 2017				61,533
Issuance (withholding) of common stock upon exercise of stock options and restricted stock awards, net	(523)			$ 1				(524)
Issuance (withholding) of common stock upon exercise of stock options and restricted stock awards, net (in shares)				1,204
Issuance of common stock under Employee Stock Purchase Plan	594							594
Issuance of common stock under Employee Stock Purchase Plan (in shares)				125
Stock compensation expense	23,478							23,478
Total other comprehensive loss	(1,134)										(1,134)
Net loss	(158,899)											(158,899)
Ending Balances at Dec. 31, 2018	63,065			$ 63				1,131,241			(2,015)	(1,066,224)
Ending Balances (in shares) at Dec. 31, 2018				62,862
Issuance (withholding) of common stock upon exercise of stock options and restricted stock awards, net	2			$ 1				1
Issuance (withholding) of common stock upon exercise of stock options and restricted stock awards, net (in shares)				975
Issuance of common stock under Employee Stock Purchase Plan	565							565
Issuance of common stock under Employee Stock Purchase Plan (in shares)				122
Issuance of common stock and preferred stock, net of issuance costs	60,113		$ 12,061	$ 20				60,093		$ 12,061
Issuance of common stock and preferred stock, net of issuance costs (in shares)				19,912			5
Stock compensation expense	25,456							25,456
Total other comprehensive loss	(372)										(372)
Net loss	(152,600)											(152,600)
Ending Balances at Dec. 31, 2019	8,290			$ 84				1,229,417			(2,387)	(1,218,824)
Ending Balances (in shares) at Dec. 31, 2019				83,871		5
Conversion of Preferred Stock	1			$ 1
Stock Issued During Period, Shares, Conversion of Convertible Securities				700
Stock Redeemed During Period, Shares, Conversion of Convertible Securities (in shares)						(1)
Issuance (withholding) of common stock upon exercise of stock options and restricted stock awards, net	289			$ 1				288
Issuance (withholding) of common stock upon exercise of stock options and restricted stock awards, net (in shares)				1,209
Issuance of common stock under Employee Stock Purchase Plan	672							672
Issuance of common stock under Employee Stock Purchase Plan (in shares)				195
Issuance of common stock and preferred stock, net of issuance costs		$ 108,537			$ 24				$ 108,513
Issuance of common stock and preferred stock, net of issuance costs (in shares)					24,215
Stock compensation expense	13,484							13,484
Total other comprehensive loss	2,660										2,660
Net loss	(75,240)											(75,240)
Ending Balances at Dec. 31, 2020	$ 58,693			$ 110				$ 1,352,374			$ 273	$ (1,294,064)
Ending Balances (in shares) at Dec. 31, 2020				110,190		4

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Operating activities
Net loss	$ (75,240)	$ (152,600)	$ (158,899)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	4,273	8,938	3,621
Amortization of right-of-use assets	2,562	3,375
(Gain) loss on disposal of property and equipment and from lease termination	(98)	18	98
Amortization of premiums (accretion of discounts) on marketable securities	535	(1,462)	(1,559)
Realized gain on available-for-sale securities	(57)
Change in fair value of warrant liability	(4,124)	7,500
Stock compensation expense	13,484	25,456	23,478
Cost of sales - amortization of intangible assets	2,500	9,217	10,862
Non-cash interest expense	2,542	4,973	2,755
Tenant improvements provided by the landlord	1,137	6,999
Gain on sale of assets	(6,851)
Changes in operating assets and liabilities:
Accounts and other receivables, net	(13,775)	(5,182)	(2,850)
Inventories, net	(22,357)	(22,310)	(18,710)
Prepaid manufacturing	(29,423)
Prepaid expenses and other current assets	(1,826)	(1,278)	(2,405)
Other assets	(229)	1,632	(3,706)
Accounts payable	(3,448)	4,848	3,417
Lease liabilities	(2,872)	(2,000)
Deferred revenue	38,212
Accrued and other liabilities	2,804	(9,376)	12,597
Net cash used in operating activities	(92,251)	(121,252)	(131,301)
Investing activities
Acquisition of technology licenses	(7,000)	(7,000)	(11,000)
Purchases of marketable securities	(201,786)	(215,191)	(213,804)
Proceeds from maturities and redemptions of marketable securities	148,565	201,810	284,457
Proceeds from sales of marketable securities	30,910
Purchases of property and equipment, net	(4,072)	(22,401)	(4,187)
Proceeds from sale of assets, net of transaction costs	6,851
Net cash (used in) provided by investing activities	(26,532)	(42,782)	55,466
Financing activities
Proceeds from long-term debt, net		74,250	99,000
Proceeds from issuances of common stock, net	108,538	65,948
Proceeds from issuances of preferred stock, net		13,586
Proceeds (tax withholding) from exercise of stock options and restricted stock awards, net	289	2	(523)
Proceeds from Employee Stock Purchase Plan	672	565	594
Net cash provided by financing activities	109,499	154,351	99,071
Effect of exchange rate changes on cash, cash equivalents and restricted cash	1,494	(184)	(482)
Net (decrease) increase in cash, cash equivalents and restricted cash	(7,790)	(9,867)	22,754
Cash, cash equivalents and restricted cash at beginning of year	40,100	49,967	27,213
Cash, cash equivalents and restricted cash at end of year	32,310	40,100	49,967
Supplemental disclosure of cash flow information
Cash paid during the year for interest	16,541	12,147	6,583
Non-cash investing and financing activities:
Non-cash acquisition of technology license			12,773
Purchases of property and equipment, not yet paid	$ 361	2,698	$ 920
Proceeds allocated to warrant liability at issuance		7,360
Right-of-use assets obtained in exchange for operating lease liabilities		$ 40,626

Organization

12 Months Ended

Dec. 31, 2020

Organization Consolidation And Presentation Of Financial Statements [Abstract]

Organization

1.	Organization

Dynavax Technologies Corporation (“we,” “our,” “us,” “Dynavax” or the “Company”), is a commercial stage biopharmaceutical company focused on developing and commercializing novel vaccines. Our first marketed product, HEPLISAV-B® (Hepatitis B Vaccine (Recombinant), Adjuvanted) is approved by the United States Food and Drug Administration (“FDA”) for prevention of infection caused by all known subtypes of hepatitis B virus in adults age 18 years and older. We also manufacture and sell CpG 1018, the adjuvant used in HEPLISAV-B. We are working to develop CpG 1018 as a premier vaccine adjuvant through research collaborations and partnerships. Current collaborations are focused on adjuvanted vaccines for COVID-19, pertussis and universal influenza. We reincorporated in Delaware in 2000.

Summary of Significant Accounting Policies

12 Months Ended

Dec. 31, 2020

Accounting Policies [Abstract]

Summary of Significant Accounting Policies

2.	Summary of Significant Accounting Policies

Basis of Presentation and Principles of Consolidation

The consolidated financial statements are prepared in accordance with U.S. generally accepted accounting principles (“GAAP”) and include our accounts and those of our wholly-owned subsidiaries, Dynavax GmbH located in Düsseldorf, Germany and Dynavax India LLP in India. All significant intercompany accounts and transactions among the entities have been eliminated from the consolidated financial statements. We operate in one business segment: discovery, development and commercialization of novel vaccines.

Liquidity and Financial Condition

As of December 31, 2020, we had cash, cash equivalents and marketable securities of $165.0 million.

The Company has incurred losses and negative cash flows from operations since its inception and expects to incur operating losses for the foreseeable future as we continue to invest in commercialization of HEPLISAV-B and development of our CpG 1018 adjuvant. If we cannot generate a sufficient amount of revenue from product sales, we will need to finance our operations through strategic alliance and licensing arrangements and/or future public or private debt and equity financings. Adequate financing may not be available to us on acceptable terms, or at all.

We currently anticipate that our cash, cash equivalents and short-term marketable securities as of December 31, 2020, and anticipated revenues from HEPLISAV-B and CpG 1018 will be sufficient to fund our operations for at least the next 12 months from the date of this filing.

Our ability to raise additional capital in the equity and debt markets, should we choose to do so, is dependent on a number of factors, including, but not limited to, the market demand for our common stock, which itself is subject to a number of development and business risks and uncertainties, our creditworthiness and the uncertainty that we would be able to raise such additional capital at a price or on terms that are favorable to us. Raising additional funds through the issuance of equity or debt securities could result in dilution to our existing stockholders, increased fixed payment obligations, or both. In addition, these securities may have rights senior to those of our common stock and could include covenants that would restrict our operations.

Use of Estimates

The preparation of financial statements in conformity with GAAP requires management to make informed estimates and assumptions that affect the amounts reported in the consolidated financial statements and accompanying notes. Management’s estimates are based on historical information available as of the date of the consolidated financial statements and various other assumptions we believe are reasonable under the circumstances. Actual results could differ materially from these estimates.

Foreign Currency Translation

We consider the local currency to be the functional currency for our international subsidiaries, Dynavax GmbH and Dynavax India LLP. Accordingly, assets and liabilities denominated in this foreign currency are translated into U.S. dollars using the exchange rate in effect on the balance sheet date. Revenues and expenses are translated at average exchange rates prevailing during the year. Currency translation adjustments arising from period to period are charged or credited to accumulated other comprehensive income (loss) in stockholders’ equity.

As of December 31, 2020 and 2019, the cumulative translation adjustments balance was $0.2 million and $(2.5) million, respectively, primarily related to the translation of Dynavax GmbH assets, liabilities and operating results from Euros to U.S. dollars. For the years ended December 31, 2020, 2019 and 2018, we reported an unrealized gain (loss) of $2.7 million, $(0.5) million and $(1.1) million, respectively. Realized gains and losses resulting from currency transactions are included in other income (expense) in the consolidated statements of operations. For the years ended December 31, 2020, 2019 and 2018, we reported a (loss) gain of $(0.8) million, $0.2 million and $0.3 million, respectively, resulting from currency transactions in our consolidated statements of operations.

Cash, Cash Equivalents and Marketable Securities

We consider all liquid investments purchased with an original maturity of three months or less and that can be liquidated without prior notice or penalty to be cash equivalents. Management determines the appropriate classification of marketable securities at the time of purchase. In accordance with our investment policy, we invest in short-term money market funds, U.S. treasuries, U.S. government agency securities and corporate debt securities. We believe these types of investments are subject to minimal credit and market risk.

We have classified our entire investment portfolio as available-for-sale and available for use in current operations and accordingly have classified all investments as short-term. Available-for-sale securities are carried at fair value based on inputs that are observable, either directly or indirectly, such as quoted market prices for similar securities; quoted prices in markets that are not active; or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the securities, with unrealized gains and losses included in accumulated other comprehensive loss in stockholders’ equity. Realized gains and losses and declines in value, if any, judged to be other than temporary on available-for-sale securities are included in interest income or expense. The cost of securities sold is based on the specific identification method. Management assesses whether declines in the fair value of investment securities are other than temporary. In determining whether a decline is other than temporary, management considers the following factors:

•

whether the investment has been in a continuous realized loss position for over 12 months;

•

the duration to maturity of our investments;

•

our intention and ability to hold the investment to maturity and if it is not more likely than not that we will be required to sell the investment before recovery of the amortized cost bases;

•

the credit rating, financial condition and near-term prospects of the issuer; and

•

the type of investments made.

To date, there have been no declines in fair value that have been identified as other than temporary.

Concentration of Credit Risk and Other Risks and Uncertainties

Financial instruments that are subject to concentration of credit risk consist primarily of cash equivalents, marketable securities and accounts receivable.

Our policy is to invest cash in institutional money market funds and marketable securities of the U.S. government and corporate issuers with high credit quality to limit the amount of credit exposure. We currently maintain a portfolio of cash equivalents and marketable securities in a variety of securities, including short-term money market funds, U.S. treasuries, U.S. government agency securities and corporate debt securities. We have not experienced any losses on our cash equivalents and marketable securities.

Our accounts receivable balance consists, primarily, of amounts due from product sales. Accounts receivable are recorded net of reserves for chargebacks, distribution fees, trade discounts and doubtful accounts. We estimate our allowance for doubtful accounts based on an evaluation of the aging of our receivables. Accounts receivable balances are written off against the allowance when it is probable that the receivable will not be collected. To date, we have not recorded any allowance for doubtful accounts.

Our product candidates will require approval from the FDA and foreign regulatory agencies before commercial sales can commence. There can be no assurance that our products will receive any of these required approvals. The denial or delay of such approvals may have a material adverse impact on our business and may impact our business in the future. In addition, after the approval of HEPLISAV-B by the FDA, there is still an ongoing risk of adverse events that did not appear during the drug approval process.

We are subject to risks common to companies in the biopharmaceutical industry, including, but not limited to, new technological innovations, clinical development risk, establishment of appropriate commercial partnerships, protection of proprietary technology, compliance with government and environmental regulations, uncertainty of market acceptance of product candidates, product liability, the volatility of our stock price and the need to obtain additional financing.

During the years ended December 31, 2020, 2019 and 2018, 77%, 100% and 83%, respectively, of our revenues were earned in the United States. As of December 31, 2020 and 2019, 57% and 62%, respectively, of our long-lived assets were located in the United States and the remaining long-lived assets were located in Germany.

Our source of product revenue consists of sales of HEPLISAV-B and CpG 1018.

We sell HEPLISAV-B to a limited number of wholesalers and specialty distributors in the U.S. All of our HEPLISAV-B revenue is from these customers. For the years ended December 31, 2020, 2019 and 2018, our three largest customers collectively represented approximately 61%, 62% and 68% of our HEPLISAV-B product revenue, respectively. All of our CpG 1018 sales were outside the U.S.

As of December 31, 2020 and 2019, our three largest customers collectively represented approximately 86% and 76% of our HEPLISAV-B trade receivable balance.

Inventories

Inventory is stated at the lower of cost or estimated net realizable value, on a first-in, first-out (“FIFO”), basis. We primarily use actual costs to determine our cost basis for inventories. Our assessment of market value requires the use of estimates regarding the net realizable value of our inventory balances, including an assessment of excess or obsolete inventory. We determine excess or obsolete inventory based on multiple factors, including an estimate of the future demand for our products, product expiration dates and current sales levels. Our assumptions of future demand for our products are inherently uncertain and if we were to change any of these judgments or estimates, it could cause a material increase or decrease in the amount of inventory reserves that we report in a particular period. For the year ended December 31, 2020 and 2019, there were no inventory reserves recognized. During 2018, we recorded $1.0 million in inventory reserves, which is included in cost of sales – product.

We consider regulatory approval of product candidates to be uncertain and product manufactured prior to regulatory approval may not be sold unless regulatory approval is obtained. As such, the manufacturing costs for product candidates incurred prior to regulatory approval are not capitalized as inventory but are expensed as research and development costs. We begin capitalization of these inventory related costs once regulatory approval is obtained.

HEPLISAV-B was approved by the FDA on November 9, 2017, at which time we began to capitalize inventory costs associated with the vial presentation of HEPLISAV-B. In March 2018, we received regulatory approval of the pre-filled syringe (“PFS”) presentation of HEPLISAV-B. Prior to FDA approval of HEPLISAV-B, all costs related to the manufacturing of HEPLISAV-B that could potentially be available to support the commercial launch, were charged to research and development expense in the period incurred as there was no alternative future use. Prior to regulatory approval of PFS, costs associated with resuming operating activities at the Düsseldorf manufacturing facility were also included in research and development expense. Subsequent to regulatory approval of PFS, costs associated with resuming manufacturing activities at the Düsseldorf facility were included in cost of sales – product, until commercial production resumed in mid-2018 at which time these costs were recorded as raw materials inventory.

Intangible Assets

We record definite-lived intangible assets related to certain capitalized milestone and sublicense payments. After determining that the pattern of future cash flows associated with intangible asset could not be reliably estimated with a high level of precision, these assets are amortized on a straight-line basis over their remaining useful lives, which are estimated to be the remaining patent life. We assess our intangible assets for impairment if indicators are present or changes in circumstance suggest that impairment may exist. No impairment has been identified during the years presented.

Long-Lived Assets

Property and equipment are recorded at cost. Depreciation is computed using the straight-line method over the estimated useful lives of the respective assets. Additions, major renewals and improvements are capitalized and repair and maintenance costs are charged to expense as incurred. Leasehold improvements are amortized over the remaining life of the initial lease term or the estimated useful lives of the assets, whichever is shorter.

We evaluate the carrying value of long-lived assets, whenever events or changes in business circumstances or our planned use of long-lived assets indicate, based on undiscounted future operating cash flows, that their carrying amounts may not be fully recoverable or that their useful lives are no longer appropriate. When an indicator of impairment exists, undiscounted future operating cash flows of long-lived assets are compared to their respective carrying value. If the carrying value is greater than the undiscounted future operating cash flows of long-lived assets, the long-lived assets are written down to their respective fair values and an impairment loss is recorded. Fair value is determined primarily using the discounted cash flows expected to be generated from the use of assets. Significant management judgment is required in the forecast of future operating results that are used in the preparation of expected cash flows. In the third quarter of 2019, we recorded accelerated depreciation of $3.0 million related to certain long-lived assets. See Note 17.

Leases

We determine if an arrangement includes a lease at inception. Operating leases are included in operating lease right-of-use assets, other current liabilities and long-term portion of lease liabilities in our consolidated balance sheets. Right-of-use assets represent our right to use an underlying asset during the lease term and lease liabilities represent our obligation to make lease payments arising from the lease. Operating lease right-of-use assets and liabilities are recognized at the lease commencement date based on the present value of lease payments over the lease term. In determining the net present value of lease payments, we use our incremental borrowing rate which represents an estimated rate of interest that we would have to pay to borrow equivalent funds on a collateralized basis at the lease commencement date.

The operating lease right-of-use assets also include any lease payments made and exclude any lease incentives. Our leases may include options to extend or terminate the lease which are included in the lease term when it is reasonably certain that we will exercise any such options. Lease expense is recognized on a straight-line basis over the expected lease term. We have elected not to apply the recognition requirements of ASC 842 for short-term leases. We have also elected the practical expedient to not separate lease components from non-lease components.

As lessors, we determine if an arrangement includes a lease at inception. We elected the practical expedient to not separate lease components from non-lease components. Sublease income is recognized on a straight-line basis over the expected lease term and is included in other income (expense) in our consolidated statements of operations.

Goodwill

Our goodwill balance relates to our April 2006 acquisition of Dynavax GmbH. Goodwill represents the excess purchase price over the fair value of tangible and intangible assets acquired and liabilities assumed. Goodwill is not amortized but is subject to an annual impairment test. In performing its goodwill impairment review, we assess qualitative factors to determine whether it is more likely than not that the fair value of its reporting unit is less than its carrying amount, including goodwill. The qualitative factors include, but are not limited to macroeconomic conditions, industry and market considerations, and the overall financial performance of the Company. If after assessing the totality of these qualitative factors, we determine that it is not more likely than not that the fair value of its reporting unit is less than its carrying amount, then no additional assessment is deemed necessary. Otherwise, we will proceed to perform a test for goodwill impairment. The first step involves comparing the estimated fair value of the related reporting unit against its carrying amount including goodwill. If the carrying amount exceeds the fair value, the amount by which the carrying amount exceeds the reporting unit’s fair value is recorded as a charge in the consolidated statements of operations. We determined that we have only one operating segment and there are no components of that operating segment that are deemed to be separate reporting units such that we have one reporting unit for purposes of our goodwill impairment testing. We evaluate goodwill for impairment on an annual basis and on an interim basis if events or changes in circumstances between annual impairment tests indicate that the asset might be impaired. No impairment has been identified for the years presented.

Revenue Recognition

We recognize revenue when the customer obtains control of promised goods or services, in an amount that reflects the consideration which we expect to receive in exchange for those goods or services. To determine revenue recognition for arrangements that we determine are within the scope of Accounting Standards Codification (“ASC”) 606, we perform the following five steps: (i) identify the contract(s) with a customer; (ii) identify the performance obligations in the contract; (iii) determine the transaction price; (iv) allocate the transaction price to the performance obligations in the contract; and (v) recognize revenue when (or as) we satisfy a performance obligation. We only apply the five-step model to contracts when it is probable that we will collect the consideration we are entitled to in exchange for the goods or services we transfer to the customer. At contract inception, once the contract is determined to be within the scope of ASC 606, we assess the goods or services promised within each contract and determine those that are performance obligations, and assess whether each promised good or service is distinct. We then recognize as revenue the amount of the transaction price that is allocated to the respective performance obligation when (or as) the performance obligation is satisfied.

Product Revenue, Net – HEPLISAV-B

We sell HEPLISAV-B to a limited number of wholesalers and specialty distributors in the U.S. (collectively, our “Customers”). Revenues from product sales are recognized when we have satisfied our performance obligation, which is the transfer of control of our product upon delivery to the Customer. The timing between the recognition of revenue for product sales and the receipt of payment is not significant. Because our standard credit terms are short-term and we expect to receive payment in less than one-year, there is no significant financing component on the related receivables. Taxes collected from Customers relating to product sales and remitted to governmental authorities are excluded from revenues.

Overall, product revenue, net, reflects our best estimates of the amount of consideration to which we are entitled based on the terms of the contract. The amount of variable consideration is included in the net sales price only to the extent that it is probable that a significant reversal in the amount of the cumulative revenue recognized will not occur in a future period. If our estimates differ significantly from actuals, we will record adjustments that would affect product revenue, net in the period of adjustment.

Reserves for Variable Consideration

Revenues from product sales are recorded at the net sales price, which includes estimates of variable consideration such as product returns, chargebacks, discounts, rebates and other fees that are offered within contracts between us and our Customers, healthcare providers, pharmacies and others relating to our product sales. We estimate variable consideration using either the most likely amount method or the expected value method, depending on the type of variable consideration and what method better predicts the amount of consideration we expect to receive. We take into consideration relevant factors such as industry data, current contractual terms, available information about Customers’ inventory, resale and chargeback data and forecasted customer buying and payment patterns, in estimating each variable consideration. The variable consideration is recorded at the time product sales is recognized, resulting in a reduction in product revenue and a reduction in accounts receivable (if the Customer offsets the amount against its accounts receivable) or as an accrued liability (if we pay the amount through our accounts payable process). Variable consideration requires significant estimates, judgment and information obtained from external sources. The amount of variable consideration is included in the net sales price only to the extent that it is probable that a significant reversal in the amount of the cumulative revenue recognized will not occur in a future period. If our estimates differ significantly from actuals, we will record adjustments that would affect product revenue, net in the period of adjustment. If we were to change any of these judgments or estimates, it could cause a material increase or decrease in the amount of revenue that we report in a particular period. We evaluate our estimates of variable considerations including, but not limited to, product returns, chargebacks and rebates, periodically or when there is an event or change in circumstances that may indicate that our estimates may change. During the fourth quarter of 2020, based on an analysis of historical product returns and customer ordering patterns, we decreased our returns reserve resulting in an increase in HEPLISAV-B product revenue, net of approximately $0.8 million. There were no material adjustments to these estimates for the years ended December 31, 2019 and 2018.

Product Returns: Consistent with industry practice, we offer our Customers a limited right of return based on the product’s expiration date for product that has been purchased from us. We estimate the amount of our product sales that may be returned by our Customers and record this estimate as a reduction of revenue in the period the related product revenue is recognized. We consider several factors in the estimation of potential product returns including expiration dates of the product shipped, the limited product return rights, available information about Customers’ inventory, shelf life of the product and other relevant factors.

Chargebacks: Our Customers subsequently resell our product to healthcare providers, pharmacies and others. In addition to distribution agreements with Customers, we enter into arrangements with qualified healthcare providers that provide for chargebacks and discounts with respect to the purchase of our product. Chargebacks represent the estimated obligations resulting from contractual commitments to sell product to qualified healthcare providers at prices lower than the list prices charged to Customers who directly purchase the product from us. Customers charge us for the difference between what they pay for the product and the ultimate selling price to the qualified healthcare providers. These reserves are established in the same period that the related revenue is recognized, resulting in a reduction of product revenue and accounts receivable. Chargeback amounts are determined at the time of resale to the qualified healthcare providers by Customers, and we issue credits for such amounts generally within a few weeks of the Customer’s notification to us of the resale. Reserves for chargebacks consists of credits that we expect to issue for units that remain in the distribution channel inventories at each reporting period end that we expect will be sold to the qualified healthcare providers, and chargebacks for units that our Customers have sold to the qualified healthcare providers, but for which credits have not been issued.

Trade Discounts and Allowances: We provide our Customers with discounts which include early payment incentives that are explicitly stated in our contracts, and are recorded as a reduction of revenue in the period the related product revenue is recognized.

Distribution Fees: Distribution fees include fees paid to certain Customers for sales order management, data and distribution services. Distribution fees are recorded as a reduction of revenue in the period the related product revenue is recognized.

Rebates: Under certain contracts, customers may obtain rebates for purchasing minimum volumes of our product. We estimate these rebates based upon the expected purchases and the contractual rebate rate and record this estimate as a reduction in revenue in the period the related revenue is recognized.

Product Revenue, Net – CpG 1018

We also sell our novel adjuvant, CpG 1018, to our collaboration partners for use in their development and/or commercialization of COVID-19 vaccine. We have determined that our collaboration partners meet the definition of customers under ASC 606. Therefore, we accounted for our CpG 1018 sales under ASC 606. Revenues from product sales are recognized when we have satisfied our performance obligation, which is the transfer of control of our product to the customer. Because the timing between the recognition of revenue for product sales and the receipt of payment is less than one year, there is no significant financing component on the related receivables.

Overall, product revenue, net, reflects our best estimates of the amount of consideration to which we are entitled based on the terms of the contract. The amount of consideration is included in the net sales price only to the extent that it is probable that a significant reversal in the amount of the cumulative revenue recognized will not occur in a future period. If our estimates differ significantly from actuals, we will record adjustments that would affect product revenue, net in the period of adjustment.

Collaboration and Manufacturing Service Revenue

We have entered into collaborative arrangements and arrangements to provide manufacturing services to other companies. Such arrangements may include promises to customers which, if capable of being distinct, are accounted for as separate performance obligations. For agreements with multiple performance obligations, we allocate estimated revenue to each performance obligation at contract inception based on the estimated transaction price of each performance obligation. Revenue allocated to each performance obligation is then recognized when we satisfy the performance obligation by transferring control of the promised good or service to the customer. Collaboration and manufacturing service revenue is included in other revenue in our consolidated statements of operations.

Research and Development Expenses and Accruals

Research and development expenses include personnel and facility-related expenses, outside contracted services including clinical trial costs, manufacturing and process development costs, research costs and other consulting services and non-cash stock-based compensation. Research and development costs are expensed as incurred. Amounts due under contracts with third parties may be either fixed fee or fee for service, and may include upfront payments, monthly payments and payments upon the completion of milestones or receipt of deliverables. Non-refundable advance payments under agreements are capitalized and expensed as the related goods are delivered or services are performed.

We contract with third parties to perform various clinical trial activities in the on-going development of potential products. The financial terms of these agreements are subject to negotiation, vary from contract to contract and may result in uneven payment flows to our vendors. Payments under the contracts depend on factors such as the achievement of certain events, successful enrollment of patients, and completion of portions of the clinical trial or similar conditions. Our accrual for clinical trials is based on estimates of the services received and efforts expended pursuant to contracts with clinical trial centers and clinical research organizations. We may terminate these contracts upon written notice and we are generally only liable for actual effort expended by the organizations to the date of termination, although in certain instances we may be further responsible for termination fees and penalties. We estimate research and development expenses and the related accrual as of each balance sheet date based on the facts and circumstances known to us at that time. There have been no material adjustments to the prior period accrued estimates for clinical trial activities during the years presented.

Stock-Based Compensation

Stock-based compensation expense for restricted stock units and stock options is estimated at the grant date based on the award’s estimated fair value and is recognized on a straight-line basis over the award’s requisite service period, assuming estimated forfeiture rates. Fair value of restricted stock units is determined at the date of grant using the Company’s closing stock price. Our determination of the fair value of stock options on the date of grant using an option-pricing model is affected by our stock price, as well as assumptions regarding a number of subjective variables. We selected the Black-Scholes option pricing model as the most appropriate method for determining the estimated fair value-based measurement of our stock options. The Black-Scholes model requires the use of subjective assumptions which determine the fair value-based measurement of stock options. These assumptions include, but are not limited to, our expected stock price volatility over the term of the awards, and projected employee stock option exercise behaviors. In the future, as additional empirical evidence regarding these input estimates becomes available, we may change or refine our approach of deriving these input estimates. These changes could impact our fair value of stock options granted in the future. Changes in the fair value of stock awards could materially impact our operating results.

Our current estimate of volatility is based on the historical volatility of our stock price. To the extent volatility in our stock price increases in the future, our estimates of the fair value of options granted in the future could increase, thereby increasing stock-based compensation cost recognized in future periods. We derive the expected term assumption primarily based on our historical settlement experience, while giving consideration to options that have not yet completed a full life cycle. Stock-based compensation cost is recognized only for awards ultimately expected to vest. Our estimate of the forfeiture rate is based primarily on our historical experience. To the extent we revise this estimate in the future, our share-based compensation cost could be materially impacted in the period of revision. There have been no material adjustments to these estimates during the years presented.

Income Taxes

The asset and liability approach is used to recognize deferred tax assets and liabilities for the expected future tax consequences of temporary differences between the carrying amounts and the tax bases of assets and liabilities. Tax law and rate changes are reflected in income in the period such changes are enacted. We include interest and penalties related to income taxes, including unrecognized tax benefits, within income tax expense.

Our income tax returns are based on calculations and assumptions that are subject to examination by the Internal Revenue Service and other tax authorities. In addition, the calculation of our tax liabilities involves dealing with uncertainties in the application of complex tax regulations. We recognize liabilities for uncertain tax positions based on a two-step process. The first step is to evaluate the tax position for recognition by determining if the weight of available evidence indicates that it is more likely than not that the position will be sustained on audit, including resolution of related appeals or litigation processes, if any. The second step is to measure the tax benefit as the largest amount that is more than 50% likely of being realized upon settlement. While we believe we have appropriate support for the positions taken on our tax returns, we regularly assess the potential outcomes of examinations by tax authorities in determining the adequacy of our provision for income taxes. We continually assess the likelihood and amount of potential adjustments and adjust the income tax provision, income taxes payable and deferred taxes in the period in which the facts that give rise to a revision become known.

Significant judgment is required in determining our provision for income taxes, our deferred tax assets and liabilities and the valuation allowance recorded against our net deferred tax assets. Deferred tax assets and liabilities are determined using the enacted tax rates in effect for the years in which those tax assets are expected to be realized. A valuation allowance is established when it is more likely than not the future realization of all or some of the deferred tax assets will not be achieved. The evaluation of the need for a valuation allowance is performed on a jurisdiction-by-jurisdiction basis, and includes a review of all available positive and negative evidence. Factors reviewed include projections of pre-tax book income for the foreseeable future, determination of cumulative pre-tax book income after permanent differences, earnings history, and reliability of forecasting.

Based on our review, we concluded that it was more likely than not that we would not be able to realize the benefit of our domestic and foreign deferred tax assets in the future. This conclusion was based on historical and projected operating performance, as well as our expectation that our operations will not generate sufficient taxable income in future periods to realize the tax benefits associated with the deferred tax assets within the statutory carryover periods. Therefore, we have maintained a full valuation allowance on our deferred tax assets as of December 31, 2020 and 2019. We will continue to assess the need for a valuation allowance on our deferred tax assets by evaluating both positive and negative evidence that may exist. Any adjustment to the net deferred tax asset valuation allowance would be recorded in the statement of operations for the period that the adjustment is determined to be required.

Restructuring

Restructuring costs are comprised of severance, other termination benefit costs, stock-based compensation expense for stock award and stock option modifications related to workforce reductions and accelerated depreciation. We recognize restructuring charges when the liability is probable and the amount is estimable. Employee termination benefits are accrued at the date management has committed to a plan of termination and affected employees have been notified of their termination date and expected severance benefits.

Recent Accounting Pronouncements

Accounting Standards Update 2016-13

In June 2016, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) No. 2016-13, Financial Instruments – Credit Losses (Topic 326): Measurement of Credit Losses of Financial Instruments. The standard changes the methodology for measuring credit losses on financial instruments and the timing of when such losses are recorded. For public business entities, excluding smaller reporting companies, this ASU is effective for fiscal years beginning after December 15, 2019. Furthermore, the one-time determination of whether an entity is eligible to be a smaller reporting company shall be based on an entity’s most recent determination as of November 15, 2019, in accordance with SEC regulations. Because we were a smaller reporting company based on the most recent determination as of November 15, 2019, this ASU and its subsequent updates, will be effective for fiscal years beginning after December 15, 2022. We are currently evaluating the impact this standard will have on our consolidated financial statements.

Accounting Standards Update 2019-12

In December 2019, the FASB issued ASU No. 2019-12, Simplifying the Accounting for Income Taxes (Topic 740). This ASU simplifies the accounting for income taxes by removing certain exceptions and improving consistent application in certain areas of Topic 740. The ASU is effective for annual periods beginning after December 15, 2020 with early adoption permitted. We adopted this ASU on January 1, 2021 and the adoption of this standard did not have a material impact on our consolidated financial statements.

Accounting Standards Update 2020-06

In August 2020, the FASB issued ASU No. 2020-06, Debt—Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging—Contracts in Entity’s Own Equity (Subtopic 815-40): Accounting for Convertible Instruments and Contracts in an Entity’s Own Equity. This ASU simplifies the accounting for convertible instruments. This ASU also requires entities to use the if-converted method for all convertible instruments in calculating diluted earnings-per-share. The ASU is effective for annual periods beginning after December 15, 2021 with early adoption permitted. We are currently evaluating the impact this standard will have on our condensed consolidated financial statements.

Fair Value Measurements

12 Months Ended

Dec. 31, 2020

Fair Value Disclosures [Abstract]

Fair Value Measurements

3.	Fair Value Measurements

We measure fair value as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. Valuation techniques used to measure fair value must maximize the use of observable inputs and minimize the use of unobservable inputs. The accounting standard describes a fair value hierarchy based on three levels of inputs, of which the first two are considered observable and the last unobservable, that may be used to measure fair value which are the following:

•

Level 1—Observable inputs, such as quoted prices in active markets for identical assets or liabilities;

•

Level 2—Inputs other than Level 1 that are observable, either directly or indirectly, such as quoted prices for similar assets or liabilities, quoted prices in markets that are not active or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities; and

•

Level 3—Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities; therefore, requiring an entity to develop its own valuation techniques and assumptions.

Assets and liabilities are classified based on the lowest level of input that is significant to the fair value measurements. We review the fair value hierarchy classification on a quarterly basis. Changes in the ability to observe valuation inputs may result in a reclassification of levels for certain assets or liabilities within the fair value hierarchy. There were no transfers between Level 1, 2 and 3 during the years ended December 31, 2020 and 2019.

The carrying amounts of cash equivalents, accounts and other receivables, accounts payable and accrued liabilities are considered reasonable estimates of their respective fair value because of their short-term nature.

Recurring Fair Value Measurements

The following table represents the fair value hierarchy for our financial assets (cash equivalents and marketable securities) and liabilities measured at fair value on a recurring basis (in thousands):

	Level 1		Level 2		Level 3		Total
December 31, 2020
Assets
Money market funds	$	23,128	$	-	$	-	$	23,128
U.S. treasuries		-		32,579		-		32,579
U.S. government agency securities		-		40,321		-		40,321
Corporate debt securities		-		61,063		-		61,063
Total assets	$	23,128	$	133,963	$	-	$	157,091
Liabilities
Warrant liability	$	-	$	-	$	10,736	$	10,736

	Level 1		Level 2		Level 3		Total
December 31, 2019
Assets
Money market funds	$	27,854	$	-	$	-	$	27,854
U.S. treasuries		-		6,517		-		6,517
U.S. government agency securities		-		51,273		-		51,273
Corporate debt securities		-		61,373		-		61,373
Total assets	$	27,854	$	119,163	$	-	$	147,017
Liabilities
Warrant liability	$	-	$	-	$	14,860	$	14,860
Sublicense liability		-		-		6,948		6,948
Total liabilities	$	-	$	-	$	21,808	$	21,808

Money market funds are highly liquid investments and are actively traded. The pricing information on these investment instruments is readily available and can be independently validated as of the measurement date. This approach results in the classification of these securities as Level 1 of the fair value hierarchy.

U.S. treasuries, U.S. government agency securities and corporate debt securities are measured at fair value using Level 2 inputs. We review trading activity and pricing for these investments as of each measurement date. When sufficient quoted pricing for identical securities is not available, we use market pricing and other observable market inputs for similar securities obtained from various third-party data providers. These inputs represent quoted prices for similar assets in active markets or these inputs have been derived from observable market data. This approach results in the classification of these securities as Level 2 of the fair value hierarchy.

Warrants were issued in connection with the underwritten public offering in August 2019 and are accounted for as a derivative liability at fair value. See Note 14. The fair value of the warrant liability is estimated using the Black-Scholes model which requires assumptions such as expected term, expected volatility and risk-free interest rate. These assumptions are subjective and require judgement to develop. Expected term is estimated using the full remaining contractual term of the warrants. We determine expected volatility based on our historical common stock price volatility. The warrant liability is classified as a Level 3 instrument as its value is based on unobservable inputs that are supported by little or no market activity.

As of December 31, 2020, we used the following key assumptions to estimate the fair value of warrant liability:

Number of shares		5,841,250
Expected term	1.1 years
Expected volatility		1.0
Risk-free interest rate		0.1	%
Dividend yield		0	%

The following table provides a summary of changes in the fair value warrant liability for year ended December 31, 2020 and 2019 (in thousands):

Balance at December 31, 2018	$	-
Fair value of warrant liability at issuance date		7,360
Increase in estimated fair value of warrant liability upon revaluation		7,500
Balance at December 31, 2019	$	14,860
Decrease in estimated fair value of warrant liability upon revaluation		(4,124	)
Balance at December 31, 2020	$	10,736

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

Cash, Cash Equivalents, Restricted Cash and Marketable Securities

12 Months Ended

Dec. 31, 2020

Investments Debt And Equity Securities [Abstract]

Cash, Cash Equivalents, Restricted Cash and Marketable Securities

4.	Cash, Cash Equivalents, Restricted Cash and Marketable Securities

The following table provides a reconciliation of cash, cash equivalents and restricted cash reported within the consolidated balance sheets that sum to the total of the same amounts shown in the consolidated statements of cash flows:

	December 31
	2020		2019		2018
Cash and cash equivalents	$	32,073	$	39,884	$	49,348
Restricted cash		237		216		619
Total cash, cash equivalents and restricted cash shown in the consolidated statements of cash flows	$	32,310	$	40,100	$	49,967

Restricted cash balances relate to certificates of deposit issued as collateral to certain letters of credit issued as security to our lease arrangements. See Note 9.

Cash, cash equivalents and marketable securities consist of the following (in thousands):

	Amortized Cost		Unrealized Gains		Unrealized Losses			Estimated Fair Value
December 31, 2020
Cash and cash equivalents:
Cash	$	7,945	$	-	$	-		$	7,945
Money market funds		23,128		-		-			23,128
Corporate debt securities		1,000		-		-			1,000
Total cash and cash equivalents		32,073		-		-			32,073
Marketable securities available-for-sale:
U.S. treasuries		32,548		31		-			32,579
U.S. government agency securities		40,313		14		(6	)		40,321
Corporate debt securities		60,071		3		(11	)		60,063
Total marketable securities available-for-sale		132,932		48		(17	)		132,963
Total cash, cash equivalents and marketable securities	$	165,005	$	48	$	(17	)	$	165,036
December 31, 2019
Cash and cash equivalents:
Cash	$	4,038	$	-	$	-		$	4,038
Money market funds		27,854		-		-			27,854
Corporate debt securities		7,992		-		-			7,992
Total cash and cash equivalents		39,884		-		-			39,884
Marketable securities available-for-sale:
U.S. treasuries		6,511		6		-			6,517
U.S. government agency securities		51,235		50		(12	)		51,273
Corporate debt securities		53,353		28		-			53,381
Total marketable securities available-for-sale		111,099		84		(12	)		111,171
Total cash, cash equivalents and marketable securities	$	150,983	$	84	$	(12	)	$	151,055

The maturities of our marketable securities available-for-sale are as follows (in thousands):

.	December 31, 2020
	Amortized Cost		Estimated Fair Value
Mature in one year or less	$	122,156	$	122,181
Mature after one year through two years		10,776		10,782
	$	132,932	$	132,963

For the year ended December 31, 2020, there were gross realized gains on investments of $0.1 million and no gross realized losses. There were no gross realized gains or losses on investments for each of the year ended December 31, 2019 and 2018. Realized gains are included in interest income in the consolidated statements of operations. All investments with unrealized losses at December 31, 2020 have been in a loss position for less than twelve months. We do not intend to sell the investments that are in an unrealized loss position before recovery of their amortized cost basis. To date, there have been no declines in fair value that have been identified as other than temporary.

Inventories, Net

12 Months Ended

Dec. 31, 2020

Inventory Disclosure [Abstract]

Inventories, net

5.	Inventories, net

The following table presents inventories, net (in thousands):

	December 31
	2020		2019
Raw materials	$	25,121	$	15,198
Work-in-process		30,293		22,890
Finished goods		8,275		3,244
Total	$	63,689	$	41,332

As of December 31, 2020, prepaid manufacturing on the consolidated balance sheets represents prepayments totaling $29.4 million made to a third-party manufacturer to produce CpG 1018 to fulfil our collaborators’ orders which we expect to be utilized in the manufacturing process and/or sold within the next twelve months. See Note 10.

Intangible Assets, Net

12 Months Ended

Dec. 31, 2020

Goodwill And Intangible Assets Disclosure [Abstract]

Intangible Assets, Net

6.	Intangible Assets, net

Intangible assets are related to certain capitalized milestone and sublicense payments. The following table presents intangible assets (in thousands):

	December 31,
	2020			2019
Intangible assets	$	19,773		$	19,773
Less accumulated amortization		(19,773	)		(17,273	)
Total	$	-		$	2,500

We recorded cost of sales - amortization of intangible assets related to capitalized sublicense payments to Merck, Sharp & Dohme Corp. (“Merck”) that we capitalized upon FDA approval of HEPLISAV-B in November 2017. See Note 10. Cost of sales – amortization of intangible assets for the year ended 2020 and 2019 was $2.5 million and $9.2 million, respectively. At December 31, 2020, intangible assets related to Merck has been fully amortized. No impairment of intangible assets has been identified during the years presented.

Sale of SD-101 Program

In May 2019, we announced a strategic restructuring to focus on our vaccine business and curtail our investment in our immuno-oncology programs. In July 2020, we sold assets related to our immuno-oncology compound, SD-101, which included intellectual property, clinical and non-clinical data, regulatory filings, clinical supply inventory and certain contracts to Surefire Medical Inc. d/b/a TriSalus Life Sciences (“TriSalus”). Pursuant to the Asset Purchase Agreement, we received $5 million upon closing of the transaction and $4 million in December 2020 as reimbursement for certain clinical trial expenses. In addition, we could receive up to an additional $250 million upon the achievement of certain development, regulatory, and commercial milestones and low double-digit royalties based on potential future net sales of product containing SD-101 compound. In connection with our agreement with Symphony Dynamo, Inc. and Symphony Dynamo Holdings LLC (“Holdings”) in November 2009, we paid $2.5 million to Holdings in August 2020. See Note 9.

For the year ended December 31, 2020, we recognized a gain on sale of SD-101 assets of $6.9 million, based on the amount of consideration received, net of any transaction costs. The $2.5 million payment to Holdings was included in selling, general and administrative expense in our consolidated statement of operations.

Property and Equipment, Net

12 Months Ended

Dec. 31, 2020

Property Plant And Equipment [Abstract]

Property and Equipment, Net

7.	Property and Equipment, net

Property and equipment consist of the following (in thousands):

	Estimated Useful	December 31,
	Life (In years)	2020			2019
Manufacturing equipment	5-14	$	13,884		$	11,484
Lab equipment	5-13		2,888			2,522
Computer equipment	3		5,255			5,009
Furniture and fixtures	3-13		2,510			1,934
Leasehold improvements	2-12		28,417			24,724
Assets in progress			1,024			4,336
			53,978			50,009
Less accumulated depreciation and amortization			(23,411	)		(17,987	)
Total		$	30,567		$	32,022

Depreciation and amortization expense on property and equipment was $4.3 million, $8.9 million and $3.6 million for the years ended December 31, 2020, 2019 and 2018, respectively. Included in depreciation and amortization expense for the year ended December 31, 2019 was accelerated depreciation of $3.0 million related to certain long-lived assets. See Note 17.

Current Accrued Liabilities and Accrued Research and Development

12 Months Ended

Dec. 31, 2020

Disclosure Component Of Current Accrued Liabilities And Accrued Research And Development [Abstract]

Current Accrued Liabilities and Accrued Research and Development

8.	Current Accrued Liabilities and Accrued Research and Development

Current accrued liabilities and accrued research and development consist of the following (in thousands):

	December 31,
	2020		2019
Payroll and related expenses	$	8,684	$	6,653
Revenue reserve accruals		6,040		3,893
Third party research expenses		1,963		2,308
Third party development expenses		842		505
Restructuring liability		-		675
Other accrued liabilities		4,375		4,888
Total	$	21,904	$	18,922

Commitments and Contingencies

12 Months Ended

Dec. 31, 2020

Commitments And Contingencies Disclosure [Abstract]

Commitments and Contingencies

9.	Commitments and Contingencies

Leases

We lease our facilities in Emeryville, California and Düsseldorf, Germany.

In July 2019, we entered into a sublease for office space located at 2100 Powell Street, Emeryville, California (the “Powell Street Sublease”) and the lease for our former corporate headquarters at 2929 Seventh Street, Berkeley, California was terminated effective August 31, 2019. Under the terms of the Powell Street Sublease, we are leasing 23,976 square feet at the rate of $3.90 per square foot, paid on a monthly basis. Rent is subject to scheduled annual increases and we are responsible for certain operating expenses and taxes throughout the life of the Powell Street Sublease. The Powell Street Sublease will continue until June 30, 2022. There is no option to extend the sublease term.

On September 17, 2018, we entered into a lease (“Horton Street Master Lease”) for office and laboratory space located at 5959 Horton Street, Emeryville, California (“Horton Street Premises”). Under the terms of the Horton Street Master Lease, we are leasing 75,662 square feet at the rate of $4.75 per square foot, paid on a monthly basis, starting on April 1, 2019 (“Commencement Date”). Rent is subject to scheduled annual increases, and we are also responsible for certain operating expenses and taxes throughout the life of Horton Street Master Lease. In connection with the Horton Street Master Lease, we are entitled to a tenant improvement allowance of up to $8.3 million, of which $8.1 million was received through December 31, 2020. The Horton Street Master Lease has an initial term of 12 years, following the Commencement Date with an option to extend the lease for two successive five-year terms. The optional periods were not included in the lease term used in determining the right-of-use asset or the lease liability as we did not consider it reasonably certain that we would exercise the options. The operating lease right-of-use assets and liabilities on our December 31, 2020 and 2019 consolidated balance sheets primarily relate to the Horton Street Master Lease.

In connection with the organizational restructuring in May 2019 (see Note 17), we did not occupy the Horton Street Premises and in July 2019, we entered into an agreement to sublease the Horton Street Premises to a third party (“Horton Street Sublease”). Under the terms of the Horton Street Sublease, we are subleasing the entire 75,662 rentable square feet at the rate of $5.50 per square foot, paid on a monthly basis. Rent is subject to scheduled annual increases and the subtenant (“Subtenant”) is responsible for certain operating expenses and taxes throughout the life of the Horton Street Sublease. The Horton Street Sublease will continue until March 31, 2031, unless earlier terminated, concurrent with the term of our Horton Street Master Lease. The Subtenant has no option to extend the sublease term. For the years ended December 31, 2020 and 2019, we recognized $7.7 million and $2.6 million, respectively of sublease income included in other income (expense) in our consolidated statements of operations.

Under the terms of the Horton Street Master Lease, rent received from the Subtenant in excess of rent paid to the landlord is shared by paying the landlord 50% of the excess rent. The excess rent is considered a variable lease payment and the total estimated payments are being recognized as additional rent expense on a straight-line basis.

Our lease expense comprises of the following (in thousands):

	Year Ended December 31,
	2020		2019		2018
Operating lease expense	$	6,267	$	6,886	$	3,953

Cash paid for amounts included in the measurement of lease liabilities for the years ended December 31, 2020 and 2019 was $6.9 million and $5.5 million, respectively and were included in change in lease liabilities in our consolidated statement of cash flows.

The balance sheet classification of our operating lease liabilities was as follows (in thousands):

	December 31, 2020		December 31, 2019
Operating lease liabilities:
Current portion of lease liabilities (included in other current liabilities)	$	3,247	$	3,039
Long-term portion of lease liabilities		34,789		37,845
Total operating lease liabilities	$	38,036	$	40,884

At December 31, 2020, the maturities of our sublease income and operating lease liabilities were as follows (in thousands):

Years ending December 31,	Sublease Income		Operating Lease Liabilities
2021	$	5,201	$	6,942
2022		5,357		6,268
2023		5,518		5,403
2024		5,684		5,547
2025		5,854		5,696
Thereafter		33,742		30,760
Total	$	61,356		60,616
Less:
Present value adjustment				(22,580	)
Total			$	38,036

The weighted average remaining lease term and the weighted average discount rate used to determine the operating lease liability were as follows:

	December 31, 2020			December 31, 2019
Weighted average remaining lease term	9.1 years			9.7 years
Weighted average discount rate		10.1	%		10.1	%

Commitments

On February 20, 2018, we entered into a $175.0 million term loan agreement (“Loan Agreement”) with CRG Servicing LLC. We borrowed $100.0 million under the Loan Agreement at closing and the remaining $75.0 million in March 2019 (collectively, “Term Loans”). At our option, until September 30, 2023, a portion of the interest payments may be paid in kind, and thereby added to the principal. Through December 31, 2020, a portion of our interest was paid in kind, which increased the principal amount of the Term Loans. Included in our total contractual obligations of $188.1 million is the principal amount of $175.0 million, paid-in-kind interest of $5.9 million and the backend facility fee of $7.2 million. The Term Loans have a maturity date of December 31, 2023, unless earlier prepaid. See Note 11.

As of December 31, 2020, our material non-cancelable purchase and other commitments, for the supply of HEPLISAV-B, CpG 1018 and for clinical research totaled $21.7 million.

During 2004, we also established a letter of credit with Deutsche Bank as security for our Düsseldorf Lease in the amount of €0.2 million (Euros). The letter of credit remained outstanding through December 31, 2020 and is collateralized by a certificate of deposit for €0.2 million, which has been included in restricted cash in the consolidated balance sheets as of December 31, 2020 and 2019.

In addition to the non-cancelable commitments included above, we have entered into contractual arrangements that obligate us to make payments to the contractual counterparties upon the occurrence of future events. In addition, in the normal course of operations, we have entered into license and other agreements and intend to continue to seek additional rights relating to compounds or technologies in connection with our discovery, manufacturing and development programs. Under the terms of the agreements, we may be required to pay future up-front fees, milestones and royalties on net sales of products originating from the licensed technologies, if any, or other payments contingent upon the occurrence of future events that cannot reasonably be estimated.

We also rely on and have entered into agreements with research institutions, contract research organizations and clinical investigators as well as clinical material manufacturers. These agreements are terminable by us upon written notice. Generally, we are liable only for actual effort expended by the organizations at any point in time during the contract through the notice period. As of December 31, 2020, our non-cancelable obligation for services and materials provided by these organizations totaled $0.3 million.

We provided $0.1 million of guarantee as of December 31, 2020 in the form of a surety bond issued to support a certain license which requires a surety bond to ensure our compliance with a certain state’s requirements. We would only be liable for any penalty of up to the guaranteed amount in the event of a non-compliance, of which the probability is remote.

In conjunction with our agreement with Holdings in November 2009, we agreed to make contingent cash payments to Holdings equal to 50% of the first $50 million from any upfront, pre-commercialization milestone or similar payments received by us from any agreement with any third party with respect to the development and/or commercialization of cancer and hepatitis C therapies originally licensed to Symphony Dynamo, Inc., including SD-101. In July 2020, we sold assets related to our SD-101 compound to TriSalus. See Note 6. We paid $2.5 million to Holdings in August 2020. We are obligated to pay Holdings 50% of the contingent pre-commercialization milestone payments that we may receive under the Asset Purchase Agreement. No liability has been recorded under this agreement as of December 31, 2020.

Contingencies

From time to time, we may be involved in claims, suits, and proceedings arising from the ordinary course of our business, including actions with respect to intellectual property claims, commercial claims, and other matters. Such claims, suits, and proceedings are inherently uncertain and their results cannot be predicted with certainty. Regardless of the outcome, such legal proceedings can have an adverse impact on us because of legal costs, diversion of management resources, and other factors. In addition, it is possible that a resolution of one or more such proceedings could result in substantial damages, fines, penalties or orders requiring a change in our business practices, which could in the future materially and adversely affect our financial position, financial statements, results of operations, or cash flows in a particular period.

Collaborative Research, Development and License Agreements

12 Months Ended

Dec. 31, 2020

Research And Development [Abstract]

Collaborative Research, Development and License Agreements

10.	Collaborative Research, Development and License Agreements

Coalition for Epidemic Preparedness Innovations

In September 2020, we entered into a Reservation Agreement for the Provision of Goods (the “Reservation Agreement”) with Coalition for Epidemic Preparedness Innovations (“CEPI”) to make available specified quantities of CpG 1018 adjuvant, for purchases at certain prices, to CEPI and its COVID-19 vaccine development partners (“CEPI Partners”). Payments received under the Reservation Agreement are considered an exchange for our CpG 1018 adjuvant which is an output of our ordinary activities. As such, we account for the arrangement under the scope of ASC 606. Payments are recorded as deferred revenue and recognized as revenue in the period when we satisfy our performance obligation to deliver CpG 1018 ordered or when CEPI’s right to place an order expires. Pursuant to the Reservation Agreement, we received $6.3 million from CEPI in September 2020 for production scale-up and a fourth quarter 2020 reservation fee.

In October 2020, CEPI terminated the Reservation Agreement and its right to place an order expired. Therefore, we recognized $6.3 million as other revenue in the fourth quarter of 2020.

Valneva SE

In April 2020, we entered into a Collaboration Agreement, as amended, with Valneva Scotland Limited (“Valneva”) to provide CpG 1018 adjuvant for use in the development of Valneva’s COVID-19 vaccine candidate. Then, in July 2020, we entered into a Clinical Collaboration Agreement, as amended, to provide additional quantities of CpG 1018 adjuvant. In September 2020, we entered into a Supply Agreement (“Supply Agreement”) with Valneva to manufacture and supply specified quantities of CpG 1018 adjuvant for use in the commercialization of Valneva's COVID-19 vaccine candidate.

We concluded that the Collaboration Agreement and the Supply Agreement were entered into at or near the same time, with the same customer and were negotiated as a package with a single commercial objective, that is the provision of CpG 1018 adjuvant to Valneva. Therefore, the Collaboration Agreement and the Supply Agreement should be combined and accounted for as a single arrangement.

Pursuant to our supply agreement with Valneva, in the fourth quarter of 2020, we received payments from Valneva totaling $20.0 million and issued an invoice to Valneva for $17.1 million for advanced payment to purchase specified quantities of CpG 1018 adjuvant in the first half of 2021. We recorded the total amount of $37.1 million as deferred revenue in our consolidated balance sheets as of December 31, 2020.

Bill & Melinda Gates Foundation Grant Agreement

In July 2020, we entered into a grant agreement (the "Grant Agreement") with Bill & Melinda Gates Foundation (“BMGF”), under which we were awarded a grant of up to $3.4 million to scale up production of our CpG 1018 adjuvant to support the global COVID-19 response (the “Project”) and we received $1.2 million of the grant from BMGF which we accounted for as deferred revenue in our consolidated balance sheets at December 31, 2020. Any grant funds, plus any income, that have not been used for, or committed to, the Project must be returned promptly to BMGF upon expiration or termination of the Grant Agreement.

We and BMGF had also planned to execute a Global Access and Strategy/Commitment Agreement (“GASC Agreement”) in connection with the Grant Agreement. Upon execution of the GASC Agreement, we would receive the remaining $2.2 million in grant funding. As of February 25, 2021, the GASC Agreement has not been executed and if it is not executed we will not receive the remaining grant funding.

Serum Institute of India Pvt. Ltd.

In June 2017, we entered into an agreement to provide Serum Institute of India Pvt. Ltd. (“SIIPL”) with technical support. In consideration, SIIPL agreed to pay us at an agreed upon hourly rate for services and reimburse certain out-of-pocket expenses. In addition, we have rights to commercialization of certain potential products manufactured at the SIIPL facility. For the years ended December 31, 2020, 2019 and 2018, we recognized collaboration revenue of $0.9 million, $0.1 million and $1.4 million, respectively.

Merck, Sharp & Dohme Corp.

In February 2018, we entered into a Sublicense Agreement (the “Sublicense Agreement”) with Merck. The Sublicense Agreement grants us, under certain non-exclusive U.S. patent rights controlled by Merck which relate to recombinant production of hepatitis B surface antigen, the right to manufacture, use, offer for sale, sell and import HEPLISAV-B in the United States and includes the right to grant further sublicenses. Under the terms of the Sublicense Agreement, we were obligated to pay $21.0 million in three installments. The first, second and third installment of $7.0 million each was paid in February 2018, 2019 and 2020, respectively. The Sublicense Agreement expired in April 2020, at which time the license became perpetual, irrevocable, fully paid-up and royalty free. As of December 31, 2020, the intangible asset has been fully amortized. At December 31, 2019, the intangible asset, net balance was $2.5 million. See Note 6.

Long-Term Debt

12 Months Ended

Dec. 31, 2020

Debt Disclosure [Abstract]

Long-Term Debt

11.	Long-Term Debt

Long-Term Debt

On February 20, 2018, we entered into a $175.0 million Loan Agreement with CRG Servicing LLC (“CRG”). Net proceeds under the Loan Agreement were $173.3 million. The Term Loans under the Loan Agreement bear interest at a rate equal to 9.5% per annum. At December 31, 2020, the effective interest rate was 10.3%. At our option, until September 30, 2023, a portion of the interest payments may be paid in kind, and thereby added to the principal. Through December 31, 2020, a portion of our interest was paid in kind, which increased the principal amount of the Term Loans to $180.9 million, net of debt discount of $1.1 million. The Term Loans have a maturity date of December 31, 2023, unless earlier prepaid. The Term Loans and paid-in-kind interest will be entirely payable at maturity.

In August 2019, we entered into a second amendment to the Loan Agreement (the “Second Amendment”). The Second Amendment amended the annual net sales threshold for sales of HEPLISAV-B, revising the twelve-month measurement periods from beginning on January 1 of each year to beginning on July 1 of each year and ending on June 30, 2023. The Second Amendment also revised the fee payable upon partial prepayment or at maturity of the Term Loans from 3% to 4% of the aggregate principal amounts.

In November 2020, we entered into a third amendment to the Loan Agreement (the “Third Amendment”). The Third Amendment modified the annual net sales threshold requirement to include sales of CpG 1018 and removed the annual net sales threshold requirement for the twelve-month period beginning July 1, 2020 and ending on June 30, 2021.

The obligations under the Loan Agreement are secured, subject to customary permitted liens and other agreed upon exceptions, by a perfected security interest in (i) all tangible and intangible assets of the Company and any future subsidiary guarantors, except for certain customary excluded property, and (ii) all of the capital stock owned by the Company and such future subsidiary guarantors (limited, in the case of the stock of certain non-U.S. subsidiaries of the Company and certain U.S. subsidiaries substantially all of whose assets consist of equity interests in non-U.S. subsidiaries, to 65% of the capital stock of such subsidiaries, subject to certain exceptions). The obligations under the Loan Agreement will be guaranteed by each of the Company’s future direct and indirect subsidiaries (other than certain non-U.S. subsidiaries of the Company and certain U.S. subsidiaries substantially all of whose assets consist of equity interests in non-U.S. subsidiaries, subject to certain exceptions). The Loan Agreement contains customary covenants and requires us to comply with a $15.0 million daily minimum combined cash and investment balance covenant and a twelve-month period revenue requirement starting on July 1, 2019 for sales of HEPLISAV-B and CpG 1018.

We recorded $19.1 million, $16.5 million and $8.8 million of interest expense related to the Term Loans during the year ended December 31, 2020, 2019 and 2018, respectively.

Revenue Recognition

12 Months Ended

Dec. 31, 2020

Revenue Recognition [Abstract]

Revenue Recognition

12.	Revenue Recognition

Our product revenue, net consisted of the following:

	Year Ended
	December 31
	2020		2019		2018
HEPLISAV-B	$	36,030	$	34,644	$	6,812
CpG 1018		3,277		-		-
Total	$	39,307	$	34,644	$	6,812

The following table summarizes balances and activities in HEPLISAV-B product revenue allowance and reserve categories for the year ended December 31, 2020 and 2019 (in thousands):

	Balance at Beginning of Period		Provisions related to current period sales		Credit or payments made during the period			Balance at End of Period
Year ended December 31, 2020:
Accounts receivable reserves(1)	$	2,701	$	11,417	$	(11,282	)	$	2,836
Revenue reserve accruals(2)	$	3,893	$	6,694	$	(4,547	)	$	6,040
Year ended December 31, 2019:
Accounts receivable reserves(1)	$	1,272	$	11,042	$	(9,613	)	$	2,701
Revenue reserve accruals(2)	$	1,033	$	6,632	$	(3,772	)	$	3,893

(1)	Reserves are for chargebacks, discounts and other fees.

(2)	Accruals are for returns, rebates and other fees

- Definition

The entire disclosure of revenue from contract with customer to transfer good or service and to transfer nonfinancial asset. Includes, but is not limited to, disaggregation of revenue, credit loss recognized from contract with customer, judgment and change in judgment related to contract with customer, and asset recognized from cost incurred to obtain or fulfill contract with customer. Excludes insurance and lease contracts.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-URI http://asc.fasb.org/topic&trid=49130388

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130551-203045

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 13
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130556-203045

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 12
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130554-203045

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 9
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130550-203045

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 12
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130554-203045

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 12
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130554-203045

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 12
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130554-203045

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130558-203045

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 12
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130554-203045

+ Details

Net Loss Per Share

12 Months Ended

Dec. 31, 2020

Earnings Per Share [Abstract]

Net Loss Per Share

13.	Net Loss Per Share

Basic net loss per share is calculated by dividing the net loss by the weighted-average number of common shares outstanding during the period. Diluted net loss per share is computed by dividing the net loss by the weighted-average number of common shares outstanding during the period and giving effect to all potentially dilutive common shares using the treasury-stock method. For purposes of this calculation, outstanding stock options, stock awards, warrants and Series B Convertible Preferred Stock are considered to be potentially dilutive common shares and are only included in the calculation of diluted net loss per share when their effect is dilutive.

	Year Ended
	December 31,
	2020			2019			2018
Numerator
Net loss	$	(75,240	)	$	(152,600	)	$	(158,899	)
Preferred stock deemed dividend		-			(3,267	)		-
Net loss allocable to common stockholders, basic		(75,240	)		(155,867	)		(158,899	)
Removal of change in fair value of warrant liability		(4,124	)		-			-
Net loss allocable to common stockholders, diluted	$	(79,364	)	$	(155,867	)	$	(158,899	)
Denominator
Weighted average shares used to compute net loss allocable to common stockholders per share, basic		100,753			72,024			62,362
Effect of dilutive warrants		751			-			-
Weighted average shares used to compute net loss allocable to common stockholders per share, diluted		101,504			72,024			62,362

The following were excluded from the calculation of diluted net loss per share as the effect of their inclusion would have been anti-dilutive:

	December 31,
	2020		2019		2018
Outstanding securities not included in diluted net loss per share calculation (in thousands):
Stock options and stock awards		10,299		9,789		7,344
Series B Convertible Preferred Stock (as converted to common stock)		4,140		4,840		-
Warrants (as exercisable into common stock)		-		5,841		-

Common Stock

12 Months Ended

Dec. 31, 2020

Preferred Stock Common Stock And Warrants [Abstract]

Common Stock

14.	Common Stock

Common Stock Outstanding

As of December 31, 2020, there were 110,189,859 shares of our common stock outstanding.

In August 2019, we sold (i) 18,525,000 shares of our common stock, par value $0.001 per share, (ii) 4,840 shares of our Series B Preferred Stock, par value $0.001 per share (“Series B Preferred Stock”) and (iii) warrants to purchase up to an aggregate of 5,841,250 shares of our common stock in an underwritten public offering (the “Offering”). Each share of common stock was sold together with a warrant to purchase 0.25 shares of common stock, at a combined price of $3.00 per share of common stock and the accompanying warrant. Each share of Series B Preferred Stock was sold together with a warrant to purchase 250 shares of common stock, at a combined price of $3,000 per share and the accompanying warrant. Proceeds from the Offering were approximately $65.6 million, net of issuance costs of $4.5 million.

Investment funds associated with Bain Capital Life Sciences Investors, LLC (Bain Capital Life Sciences) purchased approximately $35.0 million of common stock, Series B Preferred Stock and warrants in this Offering at the public offering price. Pursuant to the Offering, (i) Bain Capital Life Sciences Fund, L.P. purchased 6,826,266 shares of common stock, 3,756 shares of Series B Preferred Stock and warrants to purchase 2,645,566 shares of common stock for a total purchase price of approximately $31.7 million and (ii) BCIP Life Sciences Associates, L.P. purchased 698,734 shares of common stock, 384 shares of Series B Preferred Stock and warrants to purchase 270,684 shares of common stock for a total purchase price of approximately $3.2 million (together, “Bain Life Sciences Funds”). Bain Capital Life Sciences is the general partner of Bain Life Sciences Funds. The participation by these investors was on the same terms as the other investors in the Offering.

Following the offering, Andrew A. F. Hack, M.D., Ph.D and Managing Director of Bain Capital Life Sciences (a related party), was appointed to our board of directors.

On March 11, 2020, we entered into a warrant exchange agreement with Bain Life Sciences Funds pursuant to which we agreed that we would, upon future notice from Bain Life Sciences Funds, exchange all or a portion of the common stock warrants held by Bain Life Sciences Funds for warrants to purchase a new Series C convertible preferred stock (“Series C Warrants”). Each share of Series C convertible preferred stock would be convertible into 1,000 shares of common stock, with a conversion price of $4.50 and would have substantially identical rights to our Series B Preferred Stock. As of December 31, 2020, Bain Life Sciences Funds have not exercised their rights to exchange common stock warrants with Series C Warrants.

In May 2020, we completed an underwritten public offering of 16,100,000 shares of our common stock, par value $0.001 per share, including 2,100,000 shares sold pursuant to the full exercise of an overallotment option previously granted to the underwriters. All of the shares were offered at a price to the public of $5.00 per share. The net proceeds to us from this offering were approximately $75.4 million, after deducting the underwriting discount and other offering expenses payable by us. Bain Life Sciences Funds purchased 1,000,000 shares of common stock in the underwritten public offering. The participation by Bain Life Sciences Funds was on the same terms as the other investors in the offering.

For year ended December 31, 2020, we sold 8,005,467 shares of our common stock and received net cash proceeds of $32.3 million pursuant to a 2017 At Market Sales Agreement (“2017 ATM Agreement”) with Cowen and Company, LLC (“Cowen”) that terminated in August 2020.

On August 6, 2020, we entered into an at-the-market Sales Agreement (the “2020 ATM Agreement”) with Cowen, under which we may offer and sell from time to time, at our sole discretion, shares of our common stock having an aggregate offering price of up to $150 million through Cowen as our sales agent. We agreed to pay Cowen a commission of up to 3% of the gross sales proceeds of any common stock sold through Cowen under the 2020 ATM Agreement. For the year ended December 31, 2020, we received net cash proceeds of $0.8 million resulting from sales of 109,176 shares of our common stock pursuant to the 2020 ATM Agreement. As of December 31, 2020, we had $149.1 million remaining under the 2020 ATM Agreement. Subsequent to December 31, 2020 and through February 22, 2021, we sold 2,299,952 shares of common stock for net proceeds of $22.7 million under the 2020 ATM Agreement.

Preferred Stock Outstanding

As of December 31, 2020, there were 4,140 shares of Series B Preferred Stock outstanding.

In the second quarter of 2020, 700 shares of our Series B Preferred Stock were converted into 700,000 shares of common stock.

Each share of Series B Preferred Stock is convertible into 1,000 shares of common stock at any time at the holder’s option. However, the holder is prohibited from converting the Series B Preferred Stock into shares of common stock if, as a result of such conversion, the holder and its affiliates would own more than 4.99% of the total number of shares of common stock then issued and outstanding, which percentage may be changed at the holders’ election to a higher or lower percentage (not to exceed 19.99%) upon 61 days’ notice to the Company. In the event of liquidation, dissolution, or winding up, the holder of Series B Preferred Stock will receive payment on shares of Series B Preferred Stock (determined on an as-converted to common stock basis) equal to the amount that would be paid on our common stock. Shares of Series B Preferred Stock generally have no voting rights, except as required by law and except that the consent of holders of a majority of the outstanding Series B Preferred Stock is required to amend the terms of the Series B Preferred Stock. Holders of Series B Preferred Stock are not entitled to receive any dividends, unless and until specifically declared by our board of directors. The Series B Preferred Stock ranks on parity with our common stock as to distributions of assets upon liquidation, dissolution or winding up. The Series B Preferred Stock may rank senior to, on parity with or junior to any class or series of capital stock created in the future depending upon the specific terms of such future stock issuance.

The fair value of the common stock into which the Series B Preferred Stock is convertible exceeded the allocated purchase price of the Series B Preferred Stock by $3.3 million on the date of issuance, for which we recorded a deemed dividend. We recognized a deemed dividend equal to the number of common stock into which the Series B Preferred Stock is convertible multiplied by the difference between the value of the common stock and the Series B Preferred Stock conversion price per share on the date of issuance, which is the date the stock first became convertible. The dividend was reflected as a one-time, non-cash, deemed dividend to the holders of Series B Preferred Stock on the date of issuance.

Warrants

As of December 31, 2020, the following common stock warrants were outstanding:

Warrants Issuance Date

Shares Issuable

(in thousands)

Expiration Date

Exercise Price

per Share

Outstanding as of

December 31, 2020

(in thousands)

August 12, 2019

5,841

February 12, 2022

4.50

5,841

In February 2021, 750,000 of our common stock warrants were exercised.

Warrants were exercisable upon issuance. The holder is prohibited from exercising these warrants if, as a result of such exercise, the holder and its affiliates, would own more than 4.99% of the total number of shares of common stock then issued and outstanding, which percentage may be changed at the holders’ election to a higher or lower percentage (not to exceed 19.99%) upon 61 days’ notice to the Company.

The warrants contain provisions that may obligate us to repurchase them for an amount that does not represent fair value in the event of a change of control. Due to this provision, the warrants do not meet the criteria to be considered indexed to our own stock. Accordingly, we recorded the warrants as a derivative liability at fair value of $7.4 million on the issuance date, which was estimated using the Black-Scholes model.

The warrants will be revalued at each reporting period using the Black-Scholes model and the change in the fair value of the warrants will recognized as other income (expense) in the consolidated statements of operations. At December 31, 2020 and 2019, the estimated fair value of warrant liability was $10.7 million and $14.9 million, respectively. For the year ended December 31, 2020, we recognized $4.1 million decrease in the estimated fair value of warrant liability as income in other income (expense) in our consolidated statements of operations. For the year ended December 31, 2019, we recognized $7.5 million increase in the estimated fair value of warrant liability as a loss in other income (expense) in our consolidated statements of operations.

Equity Plans and Stock-Based Compensation

12 Months Ended

Dec. 31, 2019

Share Based Compensation [Abstract]

Equity Plans and Stock-Based Compensation

15.	Equity Plans and Stock-Based Compensation

Equity Plans

Our 2018 Equity Incentive Plan (the “2018 EIP”) is intended to be the successor to and continuation of the Dynavax Technologies Corporation 2011 Equity Incentive Plan (the “2011 EIP”). The aggregate number of shares of our common stock that may be issued under the 2018 EIP (subject to adjustment for certain changes in capitalization) is comprised of the sum of (i) 5,000,000 newly reserved shares of common stock, (ii) 140,250 unallocated shares of common stock remaining available for grant under the 2011 EIP as of May 31, 2018, and (iii) 7,477,619 shares subject to outstanding stock awards granted under the 2011 EIP and the Dynavax Technologies Corporation 2017 Inducement Award Plan that may become available from time to time as set forth in the 2018 EIP. The 2018 EIP provides for the issuance of up to 12,617,869 shares of our common stock to our employees and directors.

On May 28, 2020 and on May 30, 2019, our stockholders approved an amendment to 2018 Equity Incentive Plan (the “Amended 2018 EIP”) to, among other things, increase the aggregate number of shares of common stock authorized for issuance by 7,600,000 and 2,300,000, respectively. Under the Amended 2018 EIP, the aggregate number of shares of our common stock that may be issued to employees and directors (subject to adjustment for certain changes in capitalization) is 22,517,869.

In January 2021, we adopted the Dynavax Technologies Corporation 2021 Inducement Award Plan, pursuant to which we reserved 1,500,000 shares of common stock for issuance under the plan to be used exclusively for grants of awards to individuals who were not previously employees or directors of the Company.

The Amended 2018 EIP is administered by our Board of Directors, or a designated committee of the Board of Directors, and awards granted under the Amended 2018 EIP have a term of 7 years unless earlier terminated by the Board of Directors. As of December 31, 2020, there were 8,349,853 shares of common stock reserved for issuance under the Amended 2018 EIP.

Activity under our stock plans is set forth below:

	Shares Underlying Outstanding Options (in thousands)			Weighted-Average Exercise Price Per Share		Weighted-Average Remaining Contractual Term (years)		Aggregate Intrinsic Value (in thousands)
Balance at December 31, 2019		8,006		$	13.86
Options granted		2,003			5.76
Options exercised		(72	)		4.20
Options cancelled:
Options forfeited (unvested)		(356	)		7.24
Options expired (vested)		(1,076	)		19.75
Balance at December 31, 2020		8,505		$	11.57		4.25	$	616
Vested and expected to vest at December 31, 2020		8,314		$	11.69		4.21	$	607
Exercisable at December 31, 2020		5,551		$	14.13		3.35	$	516

The total intrinsic value of stock options exercised during the years ended December 31, 2020, 2019 and 2018 was $0.1 million, $26,000 and $0.2 million, respectively. The total intrinsic value of exercised stock options is calculated based on the difference between the exercise price and the quoted market price of our common stock as of the close of the exercise date.

The total fair value of stock options vested during the years ended December 31, 2020, 2019 and 2018 was $13.8 million, $19.5 million and $8.1 million, respectively.

Our non-vested stock awards are comprised of restricted stock units granted with performance and time-based vesting criteria. A summary of the status of non-vested restricted stock units as of December 31, 2020, and activities during 2020 are summarized as follows:

	Number of Shares (In thousands)			Weighted-Average Grant-Date Fair Value
Non-vested as of December 31, 2019		1,784		$	9.16
Granted		1,412			5.64
Vested		(1,139	)		8.18
Forfeited		(263	)		7.68
Non-vested as of December 31, 2020		1,794		$	7.23

Stock-based compensation expense related to restricted stock units was approximately $4.9 million for the year ended December 31, 2020. The aggregate intrinsic value of the restricted stock units outstanding as of December 31, 2020, based on our stock price on that date, was $8.0 million.

The total fair value of restricted stock units vested during the years ended December 31, 2020, 2019 and 2018 was $4.9 million, $7.9 million and $19.4 million, respectively.

Stock-Based Compensation

Under our stock-based compensation plans, option awards generally vest over a three-year or four-year period contingent upon continuous service and unless exercised, expire seven or ten years from the date of grant (or earlier upon termination of continuous service). The Company has also granted performance-based equity awards to certain of our employees. As of December 31, 2020, approximately 117,000 shares underlying stock options and approximately 247,000 restricted stock unit awards with performance-based vesting criteria were outstanding. None of the awards with performance-based vesting criteria were deemed probable as of December 31, 2020. We recognized stock-based compensation expense for awards with performance-based vesting criteria during the years ended December 31, 2020, 2019 and 2018 of $0.1 million, $0.5 million and $1.9 million, respectively.

The fair value of each option is estimated on the date of grant using the Black-Scholes option valuation model and the following weighted-average assumptions:

	Stock Options									Employee Stock Purchase Plan
	Year Ended December 31,									Year Ended December 31,
	2020			2019			2018			2020			2019			2018
Weighted-average fair value	$	3.91		$	4.58		$	10.75		$	2.82		$	2.72		$	8.30
Risk-free interest rate		1.0	%		2.1	%		2.5	%		0.9	%		1.9	%		2.4	%
Expected life (in years)		4.5			4.5			4.2			1.2			1.2			1.3
Expected Volatility		0.9			0.9			0.8			0.7			0.7			1.1

Expected volatility is based on historical volatility of our stock price. The expected life of options granted is estimated based on historical option exercise and employee termination data. Our senior management, who hold a majority of the options outstanding, and other employees were grouped and considered separately for valuation purposes. The risk-free rate for periods within the contractual life of the option is based on the U.S. Treasury yield curve in effect at the time of grant. Forfeiture estimates are based on historical employee turnover. The dividend yield is zero percent for all years and is based on our history and expectation of dividend payouts.

Compensation expense is based on awards ultimately expected to vest and reflects estimated forfeitures. For equity awards with time-based vesting, the fair value is amortized to expense on a straight-line basis over the vesting periods. For equity awards with performance-based vesting criteria, the fair value is amortized to expense when the achievement of the vesting criteria becomes probable. Stock-based compensation for the year ended December 31, 2020 included reversal of expenses related to cancellation of certain equity grants in the first quarter of 2020. Stock-based compensation cost for the year ended December 31, 2019 includes incremental cost of $4.1 million for accelerated vesting of stock awards and extension of exercise period of stock options in connection with the retirement of our Chief Executive Officer. See Note 17.

We recognized the following amounts of stock-based compensation expense (in thousands):

	Year Ended December 31,
	2020		2019		2018
Employees and directors stock-based compensation expense	$	13,484	$	25,456	$	23,478

	Year Ended December 31,
	2020		2019		2018
Research and development	$	1,000	$	8,058	$	9,604
Selling, general and administrative		9,585		10,224		11,761
Cost of sales - product		619		1,088		1,354
Inventory		2,280		1,964		759
Restructuring		-		4,122		-
Total	$	13,484	$	25,456	$	23,478

As of December 31, 2020, the total unrecognized compensation cost related to non-vested stock options and awards deemed probable of vesting, including all stock options with time-based vesting, net of estimated forfeitures, amounted to $15.9 million, which is expected to be recognized over the remaining weighted-average vesting period of 1.8 years. Additionally, as of December 31, 2020, the total unrecognized compensation cost related to equity awards with performance-based vesting criteria amounted to $1.2 million.

Employee Stock Purchase Plan

The Amended and Restated 2014 Employee Stock Purchase Plan (the “Purchase Plan”) provides for the purchase of common stock by eligible employees and became effective on May 28, 2014. On May 31, 2018, our stockholders approved an amendment to the Purchase Plan to increase the aggregate number of shares of common stock authorized for issuance by 600,000 shares. The purchase price per share is the lesser of (i) 85% of the fair market value of the common stock on the commencement of the two-year offer period (generally, the sixteenth day in February or August) or (ii) 85% of the fair market value of the common stock on the exercise date, which is the last day of a purchase period (generally, the fifteenth day in February or August). For the year ended December 31, 2020, employees have acquired 195,334 shares of our common stock under the Purchase Plan and 255,583 shares of our common stock remained available for future purchases under the Purchase Plan.

As of December 31, 2020, the total unrecognized compensation cost related to shares of our common stock under the Purchase Plan amounted to $0.2 million, which is expected to be recognized over the remaining weighted-average vesting period of 1 year.

Employee Benefit Plan

12 Months Ended

Dec. 31, 2020

Pension And Other Postretirement Benefit Expense [Abstract]

Employee Benefit Plan

16.	Employee Benefit Plan

We maintain a 401(k) Plan, which qualifies as a deferred salary arrangement under Section 401(k) of the Internal Revenue Code. Under the 401(k) Plan, participating employees may defer a portion of their pretax earnings. We may, at our discretion, contribute for the benefit of eligible employees. The Company’s contribution to the 401(k) Plan was approximately $0.2 million, $0.3 million and $0.2 million for the years ended December 31, 2020, 2019 and 2018, respectively.

- Definition

The entire disclosure for retirement benefits.

+ References

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+ Details

Restructuring

12 Months Ended

Dec. 31, 2020

Restructuring And Related Activities [Abstract]

Restructuring

17.	Restructuring

On May 23, 2019, we implemented a strategic organizational restructuring, principally to align our operations around our vaccine business and significantly curtail further investment in our immuno-oncology business. In connection with the restructuring, we reduced our workforce by approximately 80 positions, or approximately 36%, of U.S.-based personnel. Also, in connection with the restructuring, our Chief Executive Officer, also a member of the Board of Directors (the “Board”), submitted notice of his retirement from the Company and the Board, effective August 1, 2019. As of December 31, 2020, we have completed our restructuring activities and all costs have been incurred.

The major components of our restructuring costs are summarized as follows (in thousands):

Components of Restructuring Costs	Restructuring Costs Incurred for the Year Ended December 31, 2019
Severance and other termination benefits	$	6,277
Stock-based compensation expense (a)		4,122
Accelerated depreciation		2,957
Total restructuring cost	$	13,356

(a)

As a result of accelerated vesting of stock awards and the extension of exercise period of stock options

The outstanding restructuring liabilities are included in accrued liabilities on the consolidated balance sheets. As of December 31, 2020 and 2019, the components of the restructuring liabilities were as follows (in thousands):

	Severance and Other Termination Benefits
Balance at December 31, 2018	$	-
Severance and other termination benefits		6,277
Cash payments or settlements		(5,602	)
Balance at December 31, 2019	$	675
Cash payments or settlements		(675	)
Balance at December 31, 2020	$	-

Income Taxes

12 Months Ended

Dec. 31, 2020

Income Tax Disclosure [Abstract]

Income Taxes

18.	Income Taxes

Consolidated (loss) income before provision for income taxes consisted of the following (in thousands):

	Year Ended December 31,
	2020			2019			2018
U.S.	$	(76,324	)	$	(154,605	)	$	(160,032	)
Non U.S.		1,084			2,005			1,133
Total	$	(75,240	)	$	(152,600	)	$	(158,899	)

No income tax expense was recorded for the years ended December 31, 2020, 2019 and 2018 due to our full valuation allowance position. The difference between the consolidated income tax benefit and the amount computed by applying the federal statutory income tax rate to the consolidated loss before income taxes was as follows (in thousands):

	Year Ended December 31,
	2020			2019			2018
Income tax benefit at federal statutory rate	$	(15,756	)	$	(32,046	)	$	(33,366	)
State tax		(3,194	)		(3,153	)		(5,591	)
Business credits		(773	)		(1,757	)		(3,065	)
Uncertain tax positions		193			5,426			-
Deferred compensation charges		809			4,600			(1,165	)
Change in valuation allowance		19,009			22,715			43,134
Section 162(m) limitation		473			2,439			-
Mark-to-market of warrants		(866	)		1,575			-
Other		105			201			53
Total income tax expense	$	-		$	-		$	-

Deferred tax assets and liabilities consisted of the following (in thousands):

	December 31,
	2020			2019
Deferred tax assets:
Net operating loss carry forwards	$	224,161		$	207,385
Research tax credit carry forwards		28,578			27,883
Accruals and reserves		17,264			17,312
Capitalized research costs		-			256
Other		3,250			2,437
Total deferred tax assets		273,253			255,273
Less valuation allowance		(266,100	)		(247,092	)
Net deferred tax assets		7,153			8,181
Deferred tax liabilities:
Fixed assets		(275	)		(275	)
Operating lease right-of-use assets		(6,878	)		(7,906	)
Total deferred tax liabilities		(7,153	)		(8,181	)
Net deferred tax assets	$	-		$	-

The tax benefit of net operating losses, temporary differences and credit carryforwards is required to be recorded as an asset to the extent that management assesses that realization is “more likely than not.” Realization of the future tax benefits is dependent on our ability to generate sufficient taxable income within the carryforward period. Because of our recent history of operating losses, management believes that recognition of the deferred tax assets arising from the above-mentioned future tax benefits is currently not likely to be realized and, accordingly, has provided a full valuation allowance. The valuation allowance increased by $19.0 million and $22.3 million for the years ended December 31, 2020 and 2019, respectively, due to an increase in our deferred tax assets.

As of December 31, 2020, we had federal net operating loss carryforwards of approximately $955.0 million, which will begin to expire in the year 2021 and federal research and development tax credits of approximately $22.5 million, which expire in the years 2021 through 2040.

As of December 31, 2020, we had net operating loss carryforwards for California and other states for income tax purposes of approximately $373.2 million, which expire in the years 2021 through 2040, and California state research and development tax credits of approximately $19.8 million, which do not expire.

As of December 31, 2020, we had net operating loss carryforwards for foreign income tax purposes of approximately $6.7 million, which do not expire.

Uncertain Income Tax positions

The total amount of unrecognized tax benefits was $10.6 million and $10.3 million as of December 31, 2020 and 2019, respectively. If recognized, none of the unrecognized tax benefits would affect the effective tax rate.

The following table summarizes the activity related to our unrecognized tax benefits:

Balance at December 31, 2019	$	(10,322	)
Tax positions related to the current year
Additions		(243	)
Reductions		-
Tax positions related to the prior year
Additions		-
Reductions		-
Balance at December 31, 2020	$	(10,565	)

Our policy is to account for interest and penalties as income tax expense. As of December 31, 2020, there was no interest related to unrecognized tax benefits. No amounts of penalties related to unrecognized tax benefits were recognized in the provision for income taxes. We do not anticipate any significant change within 12 months of this reporting date of its uncertain tax positions.

The Tax Reform Act of 1986 limits the annual use of net operating loss and tax credit carryforwards in certain situations where changes occur in stock ownership of a company. In the event there is a change in ownership, as defined, the annual utilization of such carryforwards could be limited. Based on an analysis under Section 382 of the Internal Revenue Code, completed through December 31, 2018, we experienced ownership changes in 2008, 2009 and 2012 which limit the future use of its pre-change federal net operating loss carryforwards and federal research and development tax credits. We excluded these federal net operating loss carryforwards and federal research and development tax credits that will expire as a result of the annual limitations in the deferred tax assets as of December 31, 2020. A limitation calculation has not been performed with respect to the California net operating loss carryforwards and research and development tax credits and we believe that our ability to use these California net operating loss carryforwards and research and development tax credits in the future may be limited. We have not completed an analysis and a limitation calculation has not been performed subsequent to the period ending December 31, 2018. Due to equity issuances in 2020 and 2019 and changes in ownership of our common stock, we believe that our net operating losses and tax credits in the future may be further limited.

We are subject to income tax examinations for U.S. federal and state income taxes from 2001 forward. We are subject to tax examination in Germany from 2017 forward and in India from 2018 forward.

- Definition

The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.

+ References + Details

Subsequent Event

12 Months Ended

Dec. 31, 2020

Subsequent Events [Abstract]

Subsequent Event

19.	Subsequent Event

CEPI Agreement

On January 29, 2021, we entered into an agreement (the “Agreement”) with CEPI for the manufacture and reservation of a specified quantity of CpG 1018 (“CpG 1018 Materials”). The Agreement enables CEPI to direct the supply of CpG 1018 Materials to CEPI partner(s). CEPI partner(s) would purchase CpG 1018 Materials under separately negotiated agreements, subject to specified pricing requirements. The Agreement also allows us to sell CpG 1018 Materials to third-parties if not purchased by a CEPI partner within a defined period of time.

In exchange for reserving CpG 1018 Materials, CEPI has agreed to provide an interest-free, unsecured, forgivable loan of up to $99 million (the “Loan Amount”) which is equivalent to the anticipated manufacturing costs of CpG 1018 Materials. The Loan Amount will be funded in part upon the execution of the Agreement, in part upon the exercise of CEPI’s option to reserve additional quantity of CpG 1018 Materials and in part upon the release of CpG 1018 Materials. We are obligated to repay the Loan Amount, on a proportional basis, if and to the extent we receive payment for CpG 1018 Materials reserved under the Agreement. If the vaccine programs pursued by CEPI partner(s) are unsuccessful and no alternative use is found for CpG 1018 Materials reserved under the Agreement, the applicable Loan Amount will be forgiven.

Amendment to CRG Loan Agreement

On January 29, 2021, we entered into a fourth amendment to the Loan Agreement with CRG (the “Fourth Amendment”). The Fourth Amendment amended the Loan Agreement to, among other things, allow us to enter into the Agreement with CEPI and to perform our obligations thereunder.

Summary of Significant Accounting Policies (Policies)

12 Months Ended

Dec. 31, 2020

Accounting Policies [Abstract]

Basis of Presentation and Principles of Consolidation

Liquidity and Financial Condition

As of December 31, 2020, we had cash, cash equivalents and marketable securities of $165.0 million.

Use of Estimates

Foreign Currency Translation

Cash, Cash Equivalents, and Marketable Securities

Cash, Cash Equivalents and Marketable Securities

•

whether the investment has been in a continuous realized loss position for over 12 months;

•

the duration to maturity of our investments;

•

our intention and ability to hold the investment to maturity and if it is not more likely than not that we will be required to sell the investment before recovery of the amortized cost bases;

•

the credit rating, financial condition and near-term prospects of the issuer; and

•

the type of investments made.

To date, there have been no declines in fair value that have been identified as other than temporary.

Concentration of Credit Risk and Other Risks and Uncertainties

Financial instruments that are subject to concentration of credit risk consist primarily of cash equivalents, marketable securities and accounts receivable.

Our source of product revenue consists of sales of HEPLISAV-B and CpG 1018.

As of December 31, 2020 and 2019, our three largest customers collectively represented approximately 86% and 76% of our HEPLISAV-B trade receivable balance.

Product Revenue, Net – HEPLISAV-B

Reserves for Variable Consideration

Product Revenue, Net – CpG 1018

Collaboration and Manufacturing Service Revenue

Research and Development Expenses and Accruals

Stock-Based Compensation

Income Taxes

Restructuring

Recent Accounting Pronouncements

Accounting Standards Update 2016-13

Accounting Standards Update 2019-12

Accounting Standards Update 2020-06

Fair Value Measurements (Tables)

12 Months Ended

Dec. 31, 2020

Fair Value Disclosures [Abstract]

Fair Value Hierarchy for Financial Assets and Liabilities Measured at Fair Value on Recurring Basis

	Level 1		Level 2		Level 3		Total
December 31, 2020
Assets
Money market funds	$	23,128	$	-	$	-	$	23,128
U.S. treasuries		-		32,579		-		32,579
U.S. government agency securities		-		40,321		-		40,321
Corporate debt securities		-		61,063		-		61,063
Total assets	$	23,128	$	133,963	$	-	$	157,091
Liabilities
Warrant liability	$	-	$	-	$	10,736	$	10,736

	Level 1		Level 2		Level 3		Total
December 31, 2019
Assets
Money market funds	$	27,854	$	-	$	-	$	27,854
U.S. treasuries		-		6,517		-		6,517
U.S. government agency securities		-		51,273		-		51,273
Corporate debt securities		-		61,373		-		61,373
Total assets	$	27,854	$	119,163	$	-	$	147,017
Liabilities
Warrant liability	$	-	$	-	$	14,860	$	14,860
Sublicense liability		-		-		6,948		6,948
Total liabilities	$	-	$	-	$	21,808	$	21,808

Summary of Assumptions to Estimate the Fair Value of Warrant Liability

As of December 31, 2020, we used the following key assumptions to estimate the fair value of warrant liability:

Number of shares		5,841,250
Expected term	1.1 years
Expected volatility		1.0
Risk-free interest rate		0.1	%
Dividend yield		0	%

Summary of Changes in Fair Value Warrant liability

The following table provides a summary of changes in the fair value warrant liability for year ended December 31, 2020 and 2019 (in thousands):

Balance at December 31, 2018	$	-
Fair value of warrant liability at issuance date		7,360
Increase in estimated fair value of warrant liability upon revaluation		7,500
Balance at December 31, 2019	$	14,860
Decrease in estimated fair value of warrant liability upon revaluation		(4,124	)
Balance at December 31, 2020	$	10,736

Cash, Cash Equivalents, Restricted Cash and Marketable Securities (Tables)

12 Months Ended

Dec. 31, 2020

Cash Cash Equivalents And Short Term Investments [Abstract]

Reconciliation of Cash, Cash Equivalents and Restricted Cash

	December 31
	2020		2019		2018
Cash and cash equivalents	$	32,073	$	39,884	$	49,348
Restricted cash		237		216		619
Total cash, cash equivalents and restricted cash shown in the consolidated statements of cash flows	$	32,310	$	40,100	$	49,967

Summary of Cash, Cash Equivalents and Marketable Securities

Cash, cash equivalents and marketable securities consist of the following (in thousands):

	Amortized Cost		Unrealized Gains		Unrealized Losses			Estimated Fair Value
December 31, 2020
Cash and cash equivalents:
Cash	$	7,945	$	-	$	-		$	7,945
Money market funds		23,128		-		-			23,128
Corporate debt securities		1,000		-		-			1,000
Total cash and cash equivalents		32,073		-		-			32,073
Marketable securities available-for-sale:
U.S. treasuries		32,548		31		-			32,579
U.S. government agency securities		40,313		14		(6	)		40,321
Corporate debt securities		60,071		3		(11	)		60,063
Total marketable securities available-for-sale		132,932		48		(17	)		132,963
Total cash, cash equivalents and marketable securities	$	165,005	$	48	$	(17	)	$	165,036
December 31, 2019
Cash and cash equivalents:
Cash	$	4,038	$	-	$	-		$	4,038
Money market funds		27,854		-		-			27,854
Corporate debt securities		7,992		-		-			7,992
Total cash and cash equivalents		39,884		-		-			39,884
Marketable securities available-for-sale:
U.S. treasuries		6,511		6		-			6,517
U.S. government agency securities		51,235		50		(12	)		51,273
Corporate debt securities		53,353		28		-			53,381
Total marketable securities available-for-sale		111,099		84		(12	)		111,171
Total cash, cash equivalents and marketable securities	$	150,983	$	84	$	(12	)	$	151,055

Maturities of Marketable Securities Available-for-Sale

The maturities of our marketable securities available-for-sale are as follows (in thousands):

.	December 31, 2020
	Amortized Cost		Estimated Fair Value
Mature in one year or less	$	122,156	$	122,181
Mature after one year through two years		10,776		10,782
	$	132,932	$	132,963

Inventories, Net (Tables)

12 Months Ended

Dec. 31, 2020

Inventory Disclosure [Abstract]

Summary of Inventories

The following table presents inventories, net (in thousands):

	December 31
	2020		2019
Raw materials	$	25,121	$	15,198
Work-in-process		30,293		22,890
Finished goods		8,275		3,244
Total	$	63,689	$	41,332

Intangible Assets, Net (Tables)

12 Months Ended

Dec. 31, 2020

Goodwill And Intangible Assets Disclosure [Abstract]

Summary of Intangible Assets

Intangible assets are related to certain capitalized milestone and sublicense payments. The following table presents intangible assets (in thousands):

	December 31,
	2020			2019
Intangible assets	$	19,773		$	19,773
Less accumulated amortization		(19,773	)		(17,273	)
Total	$	-		$	2,500

Property and Equipment, Net (Tables)

12 Months Ended

Dec. 31, 2020

Property Plant And Equipment [Abstract]

Component of Property and Equipment, Net

Property and equipment consist of the following (in thousands):

	Estimated Useful	December 31,
	Life (In years)	2020			2019
Manufacturing equipment	5-14	$	13,884		$	11,484
Lab equipment	5-13		2,888			2,522
Computer equipment	3		5,255			5,009
Furniture and fixtures	3-13		2,510			1,934
Leasehold improvements	2-12		28,417			24,724
Assets in progress			1,024			4,336
			53,978			50,009
Less accumulated depreciation and amortization			(23,411	)		(17,987	)
Total		$	30,567		$	32,022

Current Accrued Liabilities and Accrued Research and Development (Tables)

12 Months Ended

Dec. 31, 2020

Disclosure Component Of Current Accrued Liabilities And Accrued Research And Development [Abstract]

Component of Current Accrued Liabilities and Accrued Research and Development

Current accrued liabilities and accrued research and development consist of the following (in thousands):

	December 31,
	2020		2019
Payroll and related expenses	$	8,684	$	6,653
Revenue reserve accruals		6,040		3,893
Third party research expenses		1,963		2,308
Third party development expenses		842		505
Restructuring liability		-		675
Other accrued liabilities		4,375		4,888
Total	$	21,904	$	18,922

Commitments and Contingencies (Tables)

12 Months Ended

Dec. 31, 2020

Commitments And Contingencies Disclosure [Abstract]

Summary of Operating Lease Expense

Our lease expense comprises of the following (in thousands):

	Year Ended December 31,
	2020		2019		2018
Operating lease expense	$	6,267	$	6,886	$	3,953

Summary of Balance Sheet Classification of Operating Lease Liabilities

The balance sheet classification of our operating lease liabilities was as follows (in thousands):

	December 31, 2020		December 31, 2019
Operating lease liabilities:
Current portion of lease liabilities (included in other current liabilities)	$	3,247	$	3,039
Long-term portion of lease liabilities		34,789		37,845
Total operating lease liabilities	$	38,036	$	40,884

Summary of Maturities of Sublease Income and Operating Lease Liabilities

At December 31, 2020, the maturities of our sublease income and operating lease liabilities were as follows (in thousands):

Years ending December 31,	Sublease Income		Operating Lease Liabilities
2021	$	5,201	$	6,942
2022		5,357		6,268
2023		5,518		5,403
2024		5,684		5,547
2025		5,854		5,696
Thereafter		33,742		30,760
Total	$	61,356		60,616
Less:
Present value adjustment				(22,580	)
Total			$	38,036

Summary of Weighted Average Remaining Lease Term and Weighted Average Discount Rate

The weighted average remaining lease term and the weighted average discount rate used to determine the operating lease liability were as follows:

	December 31, 2020			December 31, 2019
Weighted average remaining lease term	9.1 years			9.7 years
Weighted average discount rate		10.1	%		10.1	%

Revenue Recognition (Tables)

12 Months Ended

Dec. 31, 2020

Summary of Product Revenue

Our product revenue, net consisted of the following:

	Year Ended
	December 31
	2020		2019		2018
HEPLISAV-B	$	36,030	$	34,644	$	6,812
CpG 1018		3,277		-		-
Total	$	39,307	$	34,644	$	6,812

HEPLISAV-B

Summary of Product Revenue Allowance and Reserve Categories

The following table summarizes balances and activities in HEPLISAV-B product revenue allowance and reserve categories for the year ended December 31, 2020 and 2019 (in thousands):

	Balance at Beginning of Period		Provisions related to current period sales		Credit or payments made during the period			Balance at End of Period
Year ended December 31, 2020:
Accounts receivable reserves(1)	$	2,701	$	11,417	$	(11,282	)	$	2,836
Revenue reserve accruals(2)	$	3,893	$	6,694	$	(4,547	)	$	6,040
Year ended December 31, 2019:
Accounts receivable reserves(1)	$	1,272	$	11,042	$	(9,613	)	$	2,701
Revenue reserve accruals(2)	$	1,033	$	6,632	$	(3,772	)	$	3,893

(1)	Reserves are for chargebacks, discounts and other fees.

(2)	Accruals are for returns, rebates and other fees

Net Loss Per Share (Tables)

12 Months Ended

Dec. 31, 2020

Earnings Per Share [Abstract]

Computation of Basic and Diluted Net Loss Per Share

	Year Ended
	December 31,
	2020			2019			2018
Numerator
Net loss	$	(75,240	)	$	(152,600	)	$	(158,899	)
Preferred stock deemed dividend		-			(3,267	)		-
Net loss allocable to common stockholders, basic		(75,240	)		(155,867	)		(158,899	)
Removal of change in fair value of warrant liability		(4,124	)		-			-
Net loss allocable to common stockholders, diluted	$	(79,364	)	$	(155,867	)	$	(158,899	)
Denominator
Weighted average shares used to compute net loss allocable to common stockholders per share, basic		100,753			72,024			62,362
Effect of dilutive warrants		751			-			-
Weighted average shares used to compute net loss allocable to common stockholders per share, diluted		101,504			72,024			62,362

Outstanding Stock Options and Stock Awards Excluded from Calculation of Net Loss Per Share

	December 31,
	2020		2019		2018
Outstanding securities not included in diluted net loss per share calculation (in thousands):
Stock options and stock awards		10,299		9,789		7,344
Series B Convertible Preferred Stock (as converted to common stock)		4,140		4,840		-
Warrants (as exercisable into common stock)		-		5,841		-

Common Stock (Tables)

12 Months Ended

Dec. 31, 2020

Preferred Stock Common Stock And Warrants [Abstract]

Summary of Common Stock Warrants Outstanding

As of December 31, 2020, the following common stock warrants were outstanding:

Warrants Issuance Date

Shares Issuable

(in thousands)

Expiration Date

Exercise Price

per Share

Outstanding as of

December 31, 2020

(in thousands)

August 12, 2019

5,841

February 12, 2022

4.50

5,841

Equity Plans and Stock-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2019

Share Based Compensation [Abstract]

Option Activity under Stock-Based Compensation Plans

Activity under our stock plans is set forth below:

	Shares Underlying Outstanding Options (in thousands)			Weighted-Average Exercise Price Per Share		Weighted-Average Remaining Contractual Term (years)		Aggregate Intrinsic Value (in thousands)
Balance at December 31, 2019		8,006		$	13.86
Options granted		2,003			5.76
Options exercised		(72	)		4.20
Options cancelled:
Options forfeited (unvested)		(356	)		7.24
Options expired (vested)		(1,076	)		19.75
Balance at December 31, 2020		8,505		$	11.57		4.25	$	616
Vested and expected to vest at December 31, 2020		8,314		$	11.69		4.21	$	607
Exercisable at December 31, 2020		5,551		$	14.13		3.35	$	516

Summary of Non-vested Restricted Stock Units Activity

	Number of Shares (In thousands)			Weighted-Average Grant-Date Fair Value
Non-vested as of December 31, 2019		1,784		$	9.16
Granted		1,412			5.64
Vested		(1,139	)		8.18
Forfeited		(263	)		7.68
Non-vested as of December 31, 2020		1,794		$	7.23

Fair Value-Based Measurements and Weighted-Average Assumptions

The fair value of each option is estimated on the date of grant using the Black-Scholes option valuation model and the following weighted-average assumptions:

	Stock Options									Employee Stock Purchase Plan
	Year Ended December 31,									Year Ended December 31,
	2020			2019			2018			2020			2019			2018
Weighted-average fair value	$	3.91		$	4.58		$	10.75		$	2.82		$	2.72		$	8.30
Risk-free interest rate		1.0	%		2.1	%		2.5	%		0.9	%		1.9	%		2.4	%
Expected life (in years)		4.5			4.5			4.2			1.2			1.2			1.3
Expected Volatility		0.9			0.9			0.8			0.7			0.7			1.1

Stock-Based Compensation Expense

We recognized the following amounts of stock-based compensation expense (in thousands):

	Year Ended December 31,
	2020		2019		2018
Employees and directors stock-based compensation expense	$	13,484	$	25,456	$	23,478

	Year Ended December 31,
	2020		2019		2018
Research and development	$	1,000	$	8,058	$	9,604
Selling, general and administrative		9,585		10,224		11,761
Cost of sales - product		619		1,088		1,354
Inventory		2,280		1,964		759
Restructuring		-		4,122		-
Total	$	13,484	$	25,456	$	23,478

Restructuring (Tables)

12 Months Ended

Dec. 31, 2020

Restructuring And Related Activities [Abstract]

Schedule of Major Components of Restructuring Costs

The major components of our restructuring costs are summarized as follows (in thousands):

Components of Restructuring Costs	Restructuring Costs Incurred for the Year Ended December 31, 2019
Severance and other termination benefits	$	6,277
Stock-based compensation expense (a)		4,122
Accelerated depreciation		2,957
Total restructuring cost	$	13,356

(a)

As a result of accelerated vesting of stock awards and the extension of exercise period of stock options

Schedule of Components of the Restructuring Liabilities

	Severance and Other Termination Benefits
Balance at December 31, 2018	$	-
Severance and other termination benefits		6,277
Cash payments or settlements		(5,602	)
Balance at December 31, 2019	$	675
Cash payments or settlements		(675	)
Balance at December 31, 2020	$	-

Income Taxes (Tables)

12 Months Ended

Dec. 31, 2020

Income Tax Disclosure [Abstract]

Component of Consolidated (Loss) Income Before Provision for Income Taxes

Consolidated (loss) income before provision for income taxes consisted of the following (in thousands):

	Year Ended December 31,
	2020			2019			2018
U.S.	$	(76,324	)	$	(154,605	)	$	(160,032	)
Non U.S.		1,084			2,005			1,133
Total	$	(75,240	)	$	(152,600	)	$	(158,899	)

Difference Between Consolidated Income Tax Benefit and Amount Computed by Federal Statutory Income Tax Rate

The difference between the consolidated income tax benefit and the amount computed by applying the federal statutory income tax rate to the consolidated loss before income taxes was as follows (in thousands):

	Year Ended December 31,
	2020			2019			2018
Income tax benefit at federal statutory rate	$	(15,756	)	$	(32,046	)	$	(33,366	)
State tax		(3,194	)		(3,153	)		(5,591	)
Business credits		(773	)		(1,757	)		(3,065	)
Uncertain tax positions		193			5,426			-
Deferred compensation charges		809			4,600			(1,165	)
Change in valuation allowance		19,009			22,715			43,134
Section 162(m) limitation		473			2,439			-
Mark-to-market of warrants		(866	)		1,575			-
Other		105			201			53
Total income tax expense	$	-		$	-		$	-

Component of Deferred Tax Assets and Liabilities

Deferred tax assets and liabilities consisted of the following (in thousands):

	December 31,
	2020			2019
Deferred tax assets:
Net operating loss carry forwards	$	224,161		$	207,385
Research tax credit carry forwards		28,578			27,883
Accruals and reserves		17,264			17,312
Capitalized research costs		-			256
Other		3,250			2,437
Total deferred tax assets		273,253			255,273
Less valuation allowance		(266,100	)		(247,092	)
Net deferred tax assets		7,153			8,181
Deferred tax liabilities:
Fixed assets		(275	)		(275	)
Operating lease right-of-use assets		(6,878	)		(7,906	)
Total deferred tax liabilities		(7,153	)		(8,181	)
Net deferred tax assets	$	-		$	-

Schedule of Unrecognized Tax Benefits

The following table summarizes the activity related to our unrecognized tax benefits:

Balance at December 31, 2019	$	(10,322	)
Tax positions related to the current year
Additions		(243	)
Reductions		-
Tax positions related to the prior year
Additions		-
Reductions		-
Balance at December 31, 2020	$	(10,565	)

Organization - Additional Information (Detail)	12 Months Ended
Organization - Additional Information (Detail)	Dec. 31, 2020
HEPLISAV-B
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Minimum age approved for vaccine prevention of infection caused	18 years

Summary of Significant Accounting Policies - Additional Information (Detail)	3 Months Ended	12 Months Ended
	Sep. 30, 2019 USD ($)	Dec. 31, 2020 USD ($) Segment	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Number of operating segment \| Segment		1
Cash, cash equivalents and marketable securities		$ 165,000,000.0
Inventory reserves		0	$ 0	$ 1,000,000.0
Impairment of Intangible assets		0	0	$ 0
Accelerated depreciation related to certain long-lived assets	$ 3,000,000.0		3,000,000.0
Goodwill impairment		$ 0	$ 0		$ 0
Credit Concentration Risk
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Concentration risk, customer		three largest customers	three largest customers	three largest customers
Trade Receivable \| Credit Concentration Risk
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Concentration risk, percentage		86.00%	76.00%
Product \| Revenue \| Credit Concentration Risk
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Concentration risk, percentage		61.00%	62.00%	68.00%
HEPLISAV-B
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Increase in product revenue		$ 800,000
United States
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Percentage of revenue earned		77.00%	100.00%	83.00%
Percentage of long lived assets		57.00%	62.00%
Maximum
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Cash equivalents original maturity period		3 months
Expected period of payment to be received		1 year
Dynavax GmbH
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Cumulative translation adjustment		$ 200	$ (2,500)
Currency translation adjustments		2,700,000	(500,000)	$ (1,100,000)
Currency transaction gain (loss)		$ (800,000)	$ 200,000	$ 300,000

Fair Value Measurements - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Fair Value Disclosures [Abstract]
Transfers from level 1 to level 2	$ 0	$ 0
Transfers from level 2 to level 1	0	0
Transfers in or out of Level 3	$ 0	$ 0

Fair Value Hierarchy for Financial Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - Fair Value, Measurements, Recurring - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Assets
Total assets	$ 157,091	$ 147,017
Liabilities
Total liabilities		21,808
Money Market Funds
Assets
Total assets	23,128	27,854
U.S. Treasuries
Assets
Total assets	32,579	6,517
U.S. Government Agency Securities
Assets
Total assets	40,321	51,273
Corporate Debt Securities
Assets
Total assets	61,063	61,373
Warrant Liability
Liabilities
Total liabilities	10,736	14,860
Sublicense Liability
Liabilities
Total liabilities		6,948
Fair Value, Inputs, Level 1
Assets
Total assets	23,128	27,854
Fair Value, Inputs, Level 1 \| Money Market Funds
Assets
Total assets	23,128	27,854
Fair Value, Inputs, Level 2
Assets
Total assets	133,963	119,163
Fair Value, Inputs, Level 2 \| U.S. Treasuries
Assets
Total assets	32,579	6,517
Fair Value, Inputs, Level 2 \| U.S. Government Agency Securities
Assets
Total assets	40,321	51,273
Fair Value, Inputs, Level 2 \| Corporate Debt Securities
Assets
Total assets	61,063	61,373
Fair Value, Inputs, Level 3
Liabilities
Total liabilities		21,808
Fair Value, Inputs, Level 3 \| Warrant Liability
Liabilities
Total liabilities	$ 10,736	14,860
Fair Value, Inputs, Level 3 \| Sublicense Liability
Liabilities
Total liabilities		$ 6,948

Summary of Assumptions to Estimate the Fair Value of Warrant Liability (Detail) - Fair Value, Inputs, Level 3 shares in Thousands	Dec. 31, 2020 shares
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Number of shares	5,841,250
Expected term	1 year 1 month 6 days
Expected volatility	1.0
Risk-free interest rate	0.001
Dividend yield	0

Summary of Changes in Fair Value Warrant liability (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Decrease in estimated fair value of warrant liability upon revaluation	$ (4,124)	$ 7,500
Fair Value, Inputs, Level 3
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Balance	10,736	14,860
Fair value of warrant liability at issuance date		7,360
Increase in estimated fair value of warrant liability upon revaluation		$ 7,500
Decrease in estimated fair value of warrant liability upon revaluation	$ (4,124)

Cash, Cash Equivalents, Restricted Cash and Marketable Securities - Reconciliation of Cash, Cash Equivalents and Restricted Cash (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents [Abstract]
Cash and cash equivalents	$ 32,073	$ 39,884	$ 49,348
Restricted cash	237	216	619
Total cash, cash equivalents and restricted cash shown in the consolidated statements of cash flows	$ 32,310	$ 40,100	$ 49,967	$ 27,213

Cash, Cash Equivalents, Restricted Cash and Marketable Securities - Summary of Cash, Cash Equivalents and Marketable Securities (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Cash Cash Equivalents And Marketable Securities [Line Items]
Amortized Cost	$ 165,005	$ 150,983
Unrealized Gains	48	84
Unrealized Losses	(17)	(12)
Estimated Fair Value	165,036	151,055
Cash and Cash Equivalents
Cash Cash Equivalents And Marketable Securities [Line Items]
Amortized Cost	32,073	39,884
Estimated Fair Value	32,073	39,884
Marketable Securities Available-for-Sale
Cash Cash Equivalents And Marketable Securities [Line Items]
Amortized Cost	132,932	111,099
Unrealized Gains	48	84
Unrealized Losses	(17)	(12)
Estimated Fair Value	132,963	111,171
Cash \| Cash and Cash Equivalents
Cash Cash Equivalents And Marketable Securities [Line Items]
Amortized Cost	7,945	4,038
Estimated Fair Value	7,945	4,038
Money Market Funds \| Cash and Cash Equivalents
Cash Cash Equivalents And Marketable Securities [Line Items]
Amortized Cost	23,128	27,854
Estimated Fair Value	23,128	27,854
Corporate Debt Securities \| Cash and Cash Equivalents
Cash Cash Equivalents And Marketable Securities [Line Items]
Amortized Cost	1,000	7,992
Estimated Fair Value	1,000	7,992
Corporate Debt Securities \| Marketable Securities Available-for-Sale
Cash Cash Equivalents And Marketable Securities [Line Items]
Amortized Cost	60,071	53,353
Unrealized Gains	3	28
Unrealized Losses	(11)
Estimated Fair Value	60,063	53,381
U.S. Treasuries \| Marketable Securities Available-for-Sale
Cash Cash Equivalents And Marketable Securities [Line Items]
Amortized Cost	32,548	6,511
Unrealized Gains	31	6
Estimated Fair Value	32,579	6,517
U.S. Government Agency Securities \| Marketable Securities Available-for-Sale
Cash Cash Equivalents And Marketable Securities [Line Items]
Amortized Cost	40,313	51,235
Unrealized Gains	14	50
Unrealized Losses	(6)	(12)
Estimated Fair Value	$ 40,321	$ 51,273

Cash, Cash Equivalents, Restricted Cash and Marketable Securities - Maturities of Marketable Securities Available-for-Sale (Detail) $ in Thousands	Dec. 31, 2020 USD ($)
Amortized Cost
Mature in one year or less	$ 122,156
Mature after one year through two years	10,776
Total amortized cost	132,932
Estimated Fair Value
Mature in one year or less	122,181
Mature after one year through two years	10,782
Total estimated fair value	$ 132,963

Cash, Cash Equivalents, Restricted Cash and Marketable Securities - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Investments Debt And Equity Securities [Abstract]
Realized gains on investments	$ 100	$ 0	$ 0
Realized loss on investments	$ 0	$ 0	$ 0

Inventories, Net - Summary of Inventories (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Inventory Disclosure [Abstract]
Raw materials	$ 25,121	$ 15,198
Work-in-process	30,293	22,890
Finished goods	8,275	3,244
Total	$ 63,689	$ 41,332

Inventories, Net - Additional Information (Detail) $ in Thousands	Dec. 31, 2020 USD ($)
Inventory Disclosure [Abstract]
Prepaid manufacturing	$ 29,423

Intangible Assets, Net - Summary of Intangible Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Finite Lived Intangible Assets Net [Abstract]
Intangible assets	$ 19,773	$ 19,773
Less accumulated amortization	$ (19,773)	(17,273)
Total		$ 2,500

Intangible Assets, Net - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Finite Lived Intangible Assets [Line Items]
Cost of sales - amortization of intangible assets	$ 2,500,000	$ 9,217,000	$ 10,862,000
Impairment of intangible assets	0	0
Selling, general and administrative	79,256,000	74,986,000	$ 64,770,000
Asset Purchase Agreement
Finite Lived Intangible Assets [Line Items]
Upfront payment	5,000,000
Upfront payment receivable	4,000,000
Additional milestone payments receivable	250,000,000
Gain on sale of assets	6,900,000
Selling, general and administrative	2,500,000
Merck
Finite Lived Intangible Assets [Line Items]
Cost of sales - amortization of intangible assets	2,500,000	$ 9,200,000
Symphony Dynamo Holdings Llc \| Asset Purchase Agreement
Finite Lived Intangible Assets [Line Items]
Amount paid to third party	$ 2,500,000

Component of Property and Equipment, Net (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Property Plant And Equipment [Line Items]
Manufacturing equipment	$ 13,884	$ 11,484
Lab equipment	2,888	2,522
Computer equipment	5,255	5,009
Furniture and fixtures	2,510	1,934
Leasehold improvements	28,417	24,724
Assets in progress	1,024	4,336
Property, Plant and Equipment, Gross	53,978	50,009
Less accumulated depreciation and amortization	(23,411)	(17,987)
Total	$ 30,567	$ 32,022
Manufacturing Equipment \| Minimum
Property Plant And Equipment [Line Items]
Estimated Useful Lives (In years)	5 years
Manufacturing Equipment \| Maximum
Property Plant And Equipment [Line Items]
Estimated Useful Lives (In years)	14 years
Lab Equipment \| Minimum
Property Plant And Equipment [Line Items]
Estimated Useful Lives (In years)	5 years
Lab Equipment \| Maximum
Property Plant And Equipment [Line Items]
Estimated Useful Lives (In years)	13 years
Computer Equipment
Property Plant And Equipment [Line Items]
Estimated Useful Lives (In years)	3 years
Furniture and Fixtures \| Minimum
Property Plant And Equipment [Line Items]
Estimated Useful Lives (In years)	3 years
Furniture and Fixtures \| Maximum
Property Plant And Equipment [Line Items]
Estimated Useful Lives (In years)	13 years
Leasehold Improvements \| Minimum
Property Plant And Equipment [Line Items]
Estimated Useful Lives (In years)	2 years
Leasehold Improvements \| Maximum
Property Plant And Equipment [Line Items]
Estimated Useful Lives (In years)	12 years

Property and Equipment, Net - Additional Information (Detail) - USD ($)	3 Months Ended	12 Months Ended
	Sep. 30, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Property Plant And Equipment [Abstract]
Depreciation and amortization		$ 4,273,000	$ 8,938,000	$ 3,621,000
Accelerated depreciation charges	$ 3,000,000.0		$ 3,000,000.0

Component of Current Accrued Liabilities and Accrued Research and Development (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Accrued Liabilities Abstract
Payroll and related expenses	$ 8,684	$ 6,653
Revenue reserve accruals	6,040	3,893
Third party research expenses	1,963	2,308
Third party development expenses	842	505
Restructuring liability		675
Other accrued liabilities	4,375	4,888
Total	$ 21,904	$ 18,922

Commitments and Contingencies - Additional Information (Detail) € in Millions			1 Months Ended			12 Months Ended
	Sep. 17, 2018 USD ($) ft²	Feb. 20, 2018 USD ($)	Aug. 31, 2020 USD ($)	Jul. 31, 2019 USD ($) ft²	Nov. 30, 2009 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2020 EUR (€)	Dec. 31, 2019 EUR (€)	Mar. 29, 2019 USD ($)	Dec. 31, 2004 EUR (€)
Loss Contingencies [Line Items]
Tenant improvement allowance						$ (1,137,000)	$ (6,999,000)
Sublease income						7,706,000	2,619,000
Cash paid for amounts included in the measurement of operating lease liabilities						6,900,000	5,500,000
Non-cancelable purchase and other commitments						21,700,000
Liability under agreement						294,579,000	270,778,000
Symphony Dynamo Holdings Llc
Loss Contingencies [Line Items]
License arrangement contingent consideration percentage					50.00%
License arrangement upfront payment					$ 50,000,000
Symphony Dynamo Holdings Llc \| Asset Purchase Agreement
Loss Contingencies [Line Items]
Liability under agreement						$ 0
Contingent precommencialization milestone payments percentage						50.00%		50.00%
Amount paid to third party			$ 2,500,000
Surety Bond
Loss Contingencies [Line Items]
Guarantee to support license						$ 100,000
Services and Materials
Loss Contingencies [Line Items]
Non-cancelable purchase and other commitments						300,000
Deutsche Bank Securities
Loss Contingencies [Line Items]
Letter of credit pledged as security \| €											€ 0.2
Collateralized certificate of deposit \| €								€ 0.2	€ 0.2
CRG Servicing LLC
Loss Contingencies [Line Items]
Maximum borrowing capacity		$ 175,000,000.0
Current borrowing capacity		$ 100,000,000.0								$ 75,000,000.0
Contractual obligation						188,100,000
Principal amount						175,000,000.0
Paid-in-kind interest						5,900,000
Backend facility fee						$ 7,200,000
Debt maturity date		Dec. 31, 2023				Dec. 31, 2023
Emeryville, California (Premises) \| Horton Street Sublease
Loss Contingencies [Line Items]
Lease area \| ft²				75,662
Base rent per square feet				$ 5.50
Lease expiration date				Mar. 31, 2031
Option to extend				The Subtenant has no option to extend the sublease term.
Existence of option to extend				false
Emeryville, California (Premises) \| Horton Street Sublease \| Other Nonoperating Income (Expense)
Loss Contingencies [Line Items]
Sublease income						$ 7,700,000	$ 2,600,000
Powell Street Sublease \| Emeryville, California (Premises)
Loss Contingencies [Line Items]
Lease area \| ft²				23,976
Base rent per square feet				$ 3.90
Lease expiration date				Jun. 30, 2022
Option to extend						There is no option to extend the sublease term.
Existence of option to extend						false
Horton Street Master Lease
Loss Contingencies [Line Items]
Percentage of excess rent paid to landlord						50.00%		50.00%
Horton Street Master Lease \| Emeryville, California (Premises)
Loss Contingencies [Line Items]
Lease area \| ft²	75,662
Base rent per square feet	$ 4.75
Operations commencement date	Apr. 01, 2019
Tenant improvement allowance	$ 8,100,000
Initial lease term	12 years
Lease option to extend	The Horton Street Master Lease has an initial term of 12 years, following the Commencement Date with an option to extend the lease for two successive five-year terms
Renewal term of lease	5 years
Horton Street Master Lease \| Emeryville, California (Premises) \| Maximum
Loss Contingencies [Line Items]
Tenant improvement allowance	$ 8,300,000

Commitments and Contingencies - Summary of Operating Lease Expense (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Commitments And Contingencies Disclosure [Abstract]
Operating lease expense	$ 6,267	$ 6,886	$ 3,953

Commitments and Contingencies - Summary of Balance Sheet Classification of Operating Lease Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Commitments And Contingencies Disclosure [Abstract]
Current portion of lease liabilities (included in other current liabilities)	$ 3,247	$ 3,039
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]	us-gaap:OtherCurrentLiabilitiesMember	us-gaap:OtherCurrentLiabilitiesMember
Long-term portion of lease liabilities	$ 34,789	$ 37,845
Total operating lease liabilities	$ 38,036	$ 40,884

Commitments and Contingencies - Summary of Maturities of Sublease Income and Operating Lease Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Sublease Income
2021	$ 5,201
2022	5,357
2023	5,518
2024	5,684
2025	5,854
Thereafter	33,742
Total	61,356
Operating Lease Liabilities
2021	6,942
2022	6,268
2023	5,403
2024	5,547
2025	5,696
Thereafter	30,760
Total	60,616
Present value adjustment	(22,580)
Total	$ 38,036	$ 40,884

Commitments and Contingencies - Summary of Weighted Average Remaining Lease Term and Weighted Average Discount Rate (Detail)	Dec. 31, 2020	Dec. 31, 2019
Commitments And Contingencies Disclosure [Abstract]
Weighted average remaining lease term	9 years 1 month 6 days	9 years 8 months 12 days
Weighted average discount rate	10.10%	10.10%

Collaborative Research, Development and License Agreements - Additional Information (Detail) $ in Thousands	1 Months Ended			3 Months Ended	12 Months Ended
	Feb. 29, 2020 USD ($)	Feb. 28, 2019 USD ($)	Feb. 28, 2018 USD ($) Installment	Dec. 31, 2020 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue recognized					$ 46,551	$ 35,219	$ 8,198
Intangible assets, net						2,500
Serum Institute of India Pvt. Ltd. \| Collaboration Revenue
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue recognized					900	100	$ 1,400
Reservation Agreement \| Coalition for Epidemic Preparedness Innovations
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue recognized				$ 6,300
Reservation fees				6,300
Supply Agreement \| Valneva SE
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Deferred revenue				37,100	37,100
Grant Agreement \| Bill & Melinda Gates Foundation
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Deferred revenue				1,200	1,200
Grant Agreement \| Bill & Melinda Gates Foundation \| Maximum
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Proceeds from grant					3,400
Global Access and Strategy/Commitment Agreement \| Bill & Melinda Gates Foundation
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Grants receivable				$ 2,200	$ 2,200
Sublicense Agreement \| Merck, Sharp & Dohme Corp.
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Aggregate amount payable to acquire intangible assets			$ 21,000
Number of installments \| Installment			3
Payment upon obligation	$ 7,000	$ 7,000	$ 7,000
Agreement expiration month and year			2020-04
Intangible assets, net						$ 2,500

Long-Term Debt - Additional Information (Detail) - USD ($)		12 Months Ended
	Feb. 20, 2018	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Aug. 01, 2019	Jul. 31, 2019
Debt Instrument [Line Items]
Net proceeds from the initial term loan			$ 74,250,000	$ 99,000,000
Long-term debt, net of debt discount		$ 1,094,000	1,394,000
Loan Agreement
Debt Instrument [Line Items]
Percentage of fee payable upon partial prepayment or maturity					4.00%	3.00%
Percentage of capital stock of subsidiaries subject to certain exception	65.00%
Debt instrument, covenant daily minimum combined cash and investment balance	$ 15,000,000.0
Interest expense related to initial term loan		$ 19,100,000	$ 16,500,000	$ 8,800,000
CRG Servicing LLC
Debt Instrument [Line Items]
Maximum borrowing capacity	175,000,000.0
Net proceeds from the initial term loan	$ 173,300,000
Debt interest rate	9.50%
Debt instrument interest rate, effective percentage		10.30%
Principal amount including interest paid in kind		$ 180,900,000
Long-term debt, net of debt discount		$ 1,100,000
Debt maturity date	Dec. 31, 2023	Dec. 31, 2023

Revenue Recognition - Summary of Product Revenue (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Product Revenue Allowance and Revenue Categories [Line Items]
Total revenues	$ 46,551	$ 35,219	$ 8,198
HEPLISAV-B
Product Revenue Allowance and Revenue Categories [Line Items]
Total revenues	36,030	34,644	6,812
CpG 1018
Product Revenue Allowance and Revenue Categories [Line Items]
Total revenues	3,277
Product
Product Revenue Allowance and Revenue Categories [Line Items]
Total revenues	$ 39,307	$ 34,644	$ 6,812

- Definition

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

+ References

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+ Details

Revenue Recognition - Summary of Product Revenue Allowance and Reserve Categories (Detail) - HEPLISAV-B - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Accounts Receivable Reserves
Product Revenue Allowance and Revenue Categories [Line Items]
Balance at Beginning of Period	$ 2,701	$ 1,272
Provisions related to current period sales	11,417	11,042
Credit or payments made during the period	(11,282)	(9,613)
Balance at End of Period	2,836	2,701
Revenue Reserve Accruals
Product Revenue Allowance and Revenue Categories [Line Items]
Provisions related to current period sales	6,694	6,632
Credit or payments made during the period	(4,547)	(3,772)
Balance at Beginning of Period	3,893	1,033
Balance at End of Period	$ 6,040	$ 3,893

Computation of Basic and Diluted Net Loss Per Share (Detail) - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Disclosure Computation Of Basic And Diluted Earnings Per Share [Abstract]
Net loss	$ (75,240)	$ (152,600)	$ (158,899)
Preferred stock deemed dividend		(3,267)
Net loss allocable to common stockholders	(75,240)	(155,867)	(158,899)
Decrease in estimated fair value of warrant liability upon revaluation	(4,124)	7,500
Net loss allocable to common stockholders, diluted	$ (79,364)	$ (155,867)	$ (158,899)
Weighted average shares used to compute basic net loss per share allocable to common stockholders	100,753	72,024	62,362
Effect of dilutive warrants	751
Weighted average shares used to compute net loss allocable to common stockholders per share, diluted	101,504	72,024	62,362

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

+ Details

- Definition

Amount, after deduction of tax, noncontrolling interests, dividends on preferred stock and participating securities; of income (loss) available to common shareholders.

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+ Details

Outstanding Stock Options and Stock Awards Excluded from Calculation of Net Loss Per Share (Detail) - shares shares in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Stock Options and Stock Awards
Outstanding securities not included in diluted net loss per share calculation (in thousands):
Outstanding securities not included in diluted net loss per share calculation	10,299	9,789	7,344
Warrant Liability
Outstanding securities not included in diluted net loss per share calculation (in thousands):
Outstanding securities not included in diluted net loss per share calculation		5,841
Series B Convertible Preferred Stock
Outstanding securities not included in diluted net loss per share calculation (in thousands):
Outstanding securities not included in diluted net loss per share calculation	4,140	4,840

Common Stock - Additional Information (Detail) - USD ($)			1 Months Ended			3 Months Ended	12 Months Ended
	Aug. 06, 2020	Nov. 03, 2017	Feb. 12, 2021	May 31, 2020	Aug. 31, 2019	Jun. 30, 2020	Dec. 31, 2020	Dec. 31, 2019	Feb. 28, 2021	Mar. 11, 2020	Aug. 12, 2019
Class Of Stock [Line Items]
Common stock, shares outstanding							110,189,859	83,871,000
Issuance of common stock and preferred stock (in shares)					18,525,000
Common stock, par value					$ 0.001		$ 0.001	$ 0.001
Preferred stock, par value							$ 0.001	$ 0.001
Common Stock Shares Sold							8,005,467
Received Net Cash Proceeds							$ 32,300,000
Proceeds from issuances of common stock, net							108,538,000	$ 65,948,000
Preferred stock deemed dividend								3,267,000
Decrease in estimated fair value of warrant liability upon revaluation							(4,124,000)	$ 7,500,000
Subsequent Event
Class Of Stock [Line Items]
Number of common stock warrants exercised									750,000
Common Stock
Class Of Stock [Line Items]
Issuance of common stock and preferred stock (in shares)								19,912,000
Number of common stock allowed to purchase						700,000
Warrant Liability
Class Of Stock [Line Items]
Fair value of derivative liability							10,700,000	$ 14,900,000			$ 7,400,000
Warrant Liability \| Other Nonoperating Income (Expense)
Class Of Stock [Line Items]
Decrease in estimated fair value of warrant liability upon revaluation							$ 4,100,000	$ 7,500,000
Bain Life Sciences
Class Of Stock [Line Items]
Net cash proceeds received from issuance or sale of equity					$ 35,000,000.0
Net cash proceeds received from issuance or sale of equity					$ 35,000,000.0
Bain Capital Life Sciences Fund, L.P
Class Of Stock [Line Items]
Issuance of common stock and preferred stock (in shares)					6,826,266
Number of common stock allowed to purchase					2,645,566
Net cash proceeds received from issuance or sale of equity					$ 31,700,000
Net cash proceeds received from issuance or sale of equity					$ 31,700,000
BCIP Life Sciences Associates, L.P
Class Of Stock [Line Items]
Issuance of common stock and preferred stock (in shares)					698,734
Number of common stock allowed to purchase					270,684
Net cash proceeds received from issuance or sale of equity					$ 3,200,000
Net cash proceeds received from issuance or sale of equity					$ 3,200,000
Offering
Class Of Stock [Line Items]
Issuance of common stock and preferred stock (in shares)				2,100,000
Common stock, par value				$ 0.001
Number of common stock allowed to purchase					0.25
Combined price of common stock and warrant					$ 3.00
Net cash proceeds received from issuance or sale of equity				$ 75,400,000	$ 65,600,000
Payment of issuance costs					4,500,000
Price of common stock				$ 5.00
Net cash proceeds received from issuance or sale of equity				$ 75,400,000	$ 65,600,000
Offering \| Common Stock
Class Of Stock [Line Items]
Issuance of common stock and preferred stock (in shares)							24,215,000
Offering \| Bain Capital Life Sciences Fund, L.P
Class Of Stock [Line Items]
Issuance of common stock and preferred stock (in shares)				1,000,000
2017 ATM Agreement
Class Of Stock [Line Items]
Issuance of common stock and preferred stock (in shares)							109,176
Commission on gross sales proceeds of common stock		3.00%
Proceeds from issuances of common stock, net							$ 800,000
Remaining proceeds from common stock, under sales agreement							$ 149,100,000
2020 ATM Agreement
Class Of Stock [Line Items]
Issuance of common stock and preferred stock (in shares)			2,299,952
Proceeds from issuances of common stock, net			$ 22,700,000
Series B Convertible Preferred Stock
Class Of Stock [Line Items]
Issuance of common stock and preferred stock (in shares)					4,840	700
Preferred stock, par value					$ 0.001
Preferred stock, shares outstanding							4,140	5,000
Preferred stock deemed dividend							$ 3,300,000
Series B Convertible Preferred Stock \| Common Stock
Class Of Stock [Line Items]
Number of common stock allowed to purchase								1,000
Series B Convertible Preferred Stock \| Bain Capital Life Sciences Fund, L.P
Class Of Stock [Line Items]
Issuance of common stock and preferred stock (in shares)					3,756
Series B Convertible Preferred Stock \| BCIP Life Sciences Associates, L.P
Class Of Stock [Line Items]
Issuance of common stock and preferred stock (in shares)					384
Series B Convertible Preferred Stock \| Offering
Class Of Stock [Line Items]
Number of common stock allowed to purchase					250
Combined price of preferred stock and warrant					$ 3,000
Series C Convertible Preferred Stock \| Bain Life Sciences \| Common Stock
Class Of Stock [Line Items]
Number of common stock allowed to purchase										1,000
Conversion price per share										$ 4.50
Maximum
Class Of Stock [Line Items]
Common stock sales agreement aggregate sales proceeds	$ 150,000,000
Maximum \| Warrant Liability
Class Of Stock [Line Items]
Percentage of common stock held not to exceed for warrant exercises								19.99%
Maximum \| Offering
Class Of Stock [Line Items]
Issuance of common stock and preferred stock (in shares)				16,100,000
Warrant issued					5,841,250
Maximum \| 2017 ATM Agreement
Class Of Stock [Line Items]
Common stock sales agreement aggregate sales proceeds		$ 150,000,000
Maximum \| Series B Convertible Preferred Stock
Class Of Stock [Line Items]
Percentage of common stock held not to exceed for warrant exercises							19.99%
Minimum \| Warrant Liability
Class Of Stock [Line Items]
Percentage of common stock to be held for exercise of warrants								4.99%
Minimum \| Series B Convertible Preferred Stock
Class Of Stock [Line Items]
Percentage of common stock to be held for conversion							4.99%

Common Stock - Summary of Common Stock Warrants Outstanding (Detail) - Warrant Liability shares in Thousands	12 Months Ended
	Dec. 31, 2020 $ / shares shares
Class Of Stock [Line Items]
Warrants Issuance Date	Aug. 12, 2019
Shares Issuable \| shares	5,841
Expiration Date	Feb. 12, 2022
Exercise Price per Share \| $ / shares	$ 4.50

Equity Plans and Stock-Based Compensation - Additional Information (Detail) - USD ($)					12 Months Ended
	May 28, 2020	May 30, 2019	May 31, 2018	May 28, 2014	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Jan. 31, 2021
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Outstanding stock awards granted					8,505,000	8,006,000
Total intrinsic value of options exercised					$ 100,000	$ 26,000	$ 200,000
Total fair value of stock options vested					13,800,000	19,500,000	8,100,000
Stock-based compensation expense					$ 13,484,000	25,456,000	23,478,000
Expected dividend yield					0.00%
Increase in aggregate number of shares of common stock authorized for issuance			600,000
Restructuring
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense						4,122,000
Restricted Stock Units (RSUs)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock based compensation expense related to restricted stock					$ 4,900,000
Aggregate intrinsic value					8,000,000.0
Total fair value of restricted stock units					$ 4,900,000	$ 7,900,000	19,400,000
Restricted stock unit awards outstanding					1,794,000	1,784,000
Employee Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Outstanding stock awards granted					117,000
Performance Based Vesting Condition
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted stock unit awards outstanding					247,000
Stock-based compensation expense					$ 100,000	$ 500,000	$ 1,900,000
Maximum \| Employee Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expiration period					10 years
Options vesting period					3 years
Minimum \| Employee Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expiration period					7 years
Options vesting period					4 years
2018 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Newly reserved shares of common stock			5,000,000
Shares remaining available for future purchases			140,250
Outstanding stock awards granted			7,477,619
Expiration period			7 years
Shares reserved and approved for issuance					8,349,853
2018 Equity Incentive Plan \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares remaining available for future purchases			12,617,869
Amended 2018 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Newly reserved shares of common stock	7,600,000	2,300,000
Shares remaining available for future purchases		22,517,869
Dynavax Technologies Corporation 2021 Inducement Award Plan [Member] \| Subsequent Event
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common Stock, Capital Shares Reserved for Future Issuance								1,500,000
Time Based Vesting Schedule
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total unrecognized compensation cost related to non-vested equity awards					$ 15,900,000
Total unrecognized compensation cost, weighted-average vesting period					1 year 9 months 18 days
Performance Based Vesting Schedule
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total unrecognized compensation cost related to non-vested equity awards					$ 1,200,000
2014 Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total unrecognized compensation cost related to non-vested equity awards					$ 200,000
Total unrecognized compensation cost, weighted-average vesting period					1 year
Shares issued to employees					195,334
Shares remaining available for future purchases					255,583
2014 Employee Stock Purchase Plan \| The commencement of the offer period (generally, the sixteenth day in February or August)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Purchase price per share as percentage of fair market value of common stock				85.00%
2014 Employee Stock Purchase Plan \| The exercise date, which is the last day of a purchase period (generally, the fifteenth day in February or August)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Purchase price per share as percentage of fair market value of common stock				85.00%

Equity Plans and Stock-Based Compensation - Option Activity under Stock-Based Compensation Plans (Detail) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2020 USD ($) $ / shares shares
Shares Underlying Outstanding Options
Beginning balance \| shares	8,006
Options granted \| shares	2,003
Options exercised \| shares	(72)
Ending balance \| shares	8,505
Vested and expected to vest at December 31, 2020 \| shares	8,314
Exercisable at December 31, 2020 \| shares	5,551
Weighted-Average Exercise Price Per Share
Beginning balance \| $ / shares	$ 13.86
Options granted \| $ / shares	5.76
Options exercised \| $ / shares	4.20
Ending balance \| $ / shares	11.57
Vested and expected to vest at December 31, 2020 \| $ / shares	11.69
Exercisable at December 31, 2020 \| $ / shares	$ 14.13
Weighted-Average Remaining Contractual Term (years)
Balance at December 31, 2020	4 years 3 months
Vested and expected to vest at December 31, 2020	4 years 2 months 15 days
Exercisable at December 31, 2020	3 years 4 months 6 days
Aggregate Intrinsic Value
Balance at December 31, 2020 \| $	$ 616
Vested and expected to vest at December 31, 2020 \| $	607
Exercisable at December 31, 2020 \| $	$ 516
Unvested
Shares Underlying Outstanding Options
Options cancelled \| shares	(356)
Weighted-Average Exercise Price Per Share
Options cancelled \| $ / shares	$ 7.24
Vested
Shares Underlying Outstanding Options
Options cancelled \| shares	(1,076)
Weighted-Average Exercise Price Per Share
Options cancelled \| $ / shares	$ 19.75

Equity Plans and Stock-Based Compensation - Summary of Non-vested Restricted Stock Units Activity (Detail) - Restricted Stock Units (RSUs) shares in Thousands	12 Months Ended
	Dec. 31, 2020 $ / shares shares
Number of Shares
Non-vested, Beginning Balance \| shares	1,784
Granted \| shares	1,412
Vested \| shares	(1,139)
Forfeited \| shares	(263)
Non-vested, Ending Balance \| shares	1,794
Weighted-Average Grant-Date Fair Value Per Share
Non-vested, Beginning Balance \| $ / shares	$ 9.16
Granted \| $ / shares	5.64
Vested \| $ / shares	8.18
Forfeited \| $ / shares	7.68
Non-vested, Ending Balance \| $ / shares	$ 7.23

Equity Plans and Stock-Based Compensation - Fair Value-Based Measurements and Weighted-Average Assumptions (Detail) - $ / shares	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average fair value	$ 3.91	$ 4.58	$ 10.75
Risk-free interest rate	1.00%	2.10%	2.50%
Expected life (in years)	4 years 6 months	4 years 6 months	4 years 2 months 12 days
Expected Volatility	0.90%	0.90%	0.80%
Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average fair value	$ 2.82	$ 2.72	$ 8.30
Risk-free interest rate	0.90%	1.90%	2.40%
Expected life (in years)	1 year 2 months 12 days	1 year 2 months 12 days	1 year 3 months 18 days
Expected Volatility	0.70%	0.70%	1.10%

Equity Plans and Stock-Based Compensation - Stock-Based Compensation Expense (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Deferred Compensation Arrangement With Individual Share Based Payments [Line Items]
Employees and directors stock-based compensation expense	$ 13,484	$ 25,456	$ 23,478
Inventory
Deferred Compensation Arrangement With Individual Share Based Payments [Line Items]
Stock-based compensation expense	2,280	1,964	759
Research and Development
Deferred Compensation Arrangement With Individual Share Based Payments [Line Items]
Stock-based compensation expense	1,000	8,058	9,604
Selling, General and Administrative
Deferred Compensation Arrangement With Individual Share Based Payments [Line Items]
Stock-based compensation expense	9,585	10,224	11,761
Cost of Sales - Product
Deferred Compensation Arrangement With Individual Share Based Payments [Line Items]
Stock-based compensation expense	$ 619	1,088	$ 1,354
Restructuring
Deferred Compensation Arrangement With Individual Share Based Payments [Line Items]
Stock-based compensation expense		$ 4,122

Employee Benefit Plan - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Pension And Other Postretirement Benefit Expense [Abstract]
Contributions to 401 (k) plan	$ 0.2	$ 0.3	$ 0.2

- Definition

Amount of contribution received by defined benefit plan from employer which increases plan assets.

+ References + Details

Restructuring - Additional Information (Detail) - Position		12 Months Ended
	May 23, 2019	Dec. 31, 2020
Restructuring And Related Activities [Abstract]
Number of positions reduced in global workforce	80
Percentage of reduction in global workforce	36.00%
Restructuring completion date		Dec. 31, 2020

Restructuring - Schedule of Major Components of Restructuring Costs (Detail) $ in Thousands	Dec. 31, 2019 USD ($)
Restructuring Cost And Reserve [Line Items]
Restructuring Costs Incurred for the Year Ended December 31, 2019	$ 13,356
Severance and Other Termination Benefits
Restructuring Cost And Reserve [Line Items]
Restructuring Costs Incurred for the Year Ended December 31, 2019	6,277
Stock-Based Compensation Expense
Restructuring Cost And Reserve [Line Items]
Restructuring Costs Incurred for the Year Ended December 31, 2019	4,122
Accelerated Depreciation
Restructuring Cost And Reserve [Line Items]
Restructuring Costs Incurred for the Year Ended December 31, 2019	$ 2,957

Restructuring - Schedule of Components of the Restructuring Liabilities (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Restructuring Cost And Reserve [Line Items]
Severance and other termination benefits		$ 13,356
Employee Severance And Other Benefits
Restructuring Cost And Reserve [Line Items]
Balance at December 31, 2018	$ 675
Severance and other termination benefits		6,277
Cash payments or settlements	$ (675)	(5,602)
Balance at December 31, 2019		$ 675

Component of Consolidated (Loss) Income Before Provision for Income Taxes (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
U.S.	$ (76,324)	$ (154,605)	$ (160,032)
Non U.S.	1,084	2,005	1,133
Total	$ (75,240)	$ (152,600)	$ (158,899)

Income Taxes - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Line Items]
Income tax expense	$ 0	$ 0	$ 0
Increase (decrease) in valuation allowance	19,000,000.0	22,300,000
Unrecognized tax benefits	10,565,000	$ 10,322,000
Unrecognized tax benefits would affect the effective tax rate	0
Interest related to unrecognized tax benefits	0
Penalties related to unrecognized tax benefits	0
Federal
Income Tax Disclosure [Line Items]
Net operating loss carryforwards	$ 955,000,000.0
Federal \| Minimum
Income Tax Disclosure [Line Items]
Net operating loss carryforwards, expiration year	2021
Federal \| Research And Development Tax Credits
Income Tax Disclosure [Line Items]
Tax credit carryforward amount	$ 22,500,000
Federal \| Research And Development Tax Credits \| Minimum
Income Tax Disclosure [Line Items]
Tax credit carryforward amount, expiration year	2021
Federal \| Research And Development Tax Credits \| Maximum
Income Tax Disclosure [Line Items]
Tax credit carryforward amount, expiration year	2040
California and Other States
Income Tax Disclosure [Line Items]
Net operating loss carryforwards	$ 373,200,000
California and Other States \| Minimum
Income Tax Disclosure [Line Items]
Net operating loss carryforwards, expiration year	2021
California and Other States \| Maximum
Income Tax Disclosure [Line Items]
Net operating loss carryforwards, expiration year	2040
California State \| Research And Development Tax Credits
Income Tax Disclosure [Line Items]
Tax credit carryforward amount	$ 19,800,000
Foreign
Income Tax Disclosure [Line Items]
Net operating loss carryforwards	$ 6,700,000

Difference between Consolidated Income Tax Benefit and Amount Computed by Federal Statutory Income Tax Rate (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Income tax benefit at federal statutory rate	$ (15,756,000)	$ (32,046,000)	$ (33,366,000)
State tax	(3,194,000)	(3,153,000)	(5,591,000)
Business credits	(773,000)	(1,757,000)	(3,065,000)
Uncertain tax positions	193,000	5,426,000
Deferred compensation charges	809,000	4,600,000	(1,165,000)
Change in valuation allowance	19,009,000	22,715,000	43,134,000
Section 162(m) limitation	473,000	2,439,000
Mark-to-market of warrants	(866,000)	1,575,000
Other	105,000	201,000	53,000
Total income tax expense	$ 0	$ 0	$ 0

Component of Deferred Tax Assets and Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Deferred tax assets:
Net operating loss carry forwards	$ 224,161	$ 207,385
Research tax credit carry forwards	28,578	27,883
Accruals and reserves	17,264	17,312
Capitalized research costs		256
Other	3,250	2,437
Total deferred tax assets	273,253	255,273
Less valuation allowance	(266,100)	(247,092)
Net deferred tax assets	7,153	8,181
Deferred tax liabilities:
Fixed assets	(275)	(275)
Operating lease right-of-use assets	(6,878)	(7,906)
Total deferred tax liabilities	$ (7,153)	$ (8,181)

Schedule of Unrecognized Tax Benefits (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2020 USD ($)
Income Tax Disclosure [Abstract]
Balance at December 31, 2019	$ (10,322)
Tax positions related to the current year, Additions	(243)
Balance at December 31, 2020	$ (10,565)

Subsequent Event - Additional Information (Detail) $ in Millions	Jan. 29, 2021 USD ($)
Maximum \| Reservation Agreement \| Coalition for Epidemic Preparedness Innovations \| Subsequent Event
Subsequent Event [Line Items]
Interest- free unsecured forgivable loan	$ 99