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Document and Entity Information - USD ($)	12 Months Ended
Document and Entity Information - USD ($)	Dec. 31, 2013	Feb. 28, 2014	Jun. 28, 2013
Document Information [Line Items]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2013
Document Fiscal Year Focus	2013
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	No
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding		262,855,958
Entity Public Float			$ 105,519,624

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2013	Dec. 31, 2012
Current assets:
Cash and cash equivalents	$ 23,122	$ 7,599
Marketable securities available-for-sale	166,254	117,531
Accounts receivable	1,627	1,005
Prepaid expenses and other current assets	1,375	2,052
Total current assets	192,378	128,187
Property and equipment, net	8,706	7,965
Goodwill	2,579	2,475
Restricted cash	662	652
Other assets	297	473
Total assets	204,622	139,752
Current liabilities:
Accounts payable	1,901	2,166
Accrued liabilities	8,166	10,063
Deferred revenues	6,125	6,785
Total current liabilities	16,192	19,014
Deferred revenues, net of current portion	1,173	5,283
Other long-term liabilities	963	629
Total liabilities	18,328	24,926
Commitments and contingencies (Note 9)
Stockholders’ equity:
Preferred stock
Common stock: $0.001 par value; 350,000 and 250,000 shares authorized at December 31, 2013 and 2012, respectively; 262,796 and 182,792 shares issued and outstanding at December 31, 2013 and 2012, respectively	263	183
Additional paid-in capital	688,390	550,729
Total accumulated other comprehensive loss	(148)	(595)
Accumulated deficit	(502,211)	(435,491)
Total stockholders’ equity	186,294	114,826
Total liabilities and stockholders’ equity	204,622	139,752
Series B Convertible Preferred Stock
Stockholders’ equity:
Preferred stock

Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Revenues:
Collaboration revenue	$ 4,929	$ 4,610	$ 17,190
Grant revenue	5,138	3,939	3,110
Service and license revenue	1,184	1,165	1,314
Total revenues	11,251	9,714	21,614
Operating expenses:
Research and development	50,870	49,146	51,322
General and administrative	25,943	28,164	17,570
Unoccupied facility expense	926
Amortization of intangible assets	0	0	299
Total operating expenses	77,739	77,310	69,191
Loss from operations	(66,488)	(67,596)	(47,577)
Other income (expense):
Interest income	116	291	103
Interest expense		(2,351)	(1,957)
Other income (expense)	(348)	(293)	834
Net loss	(66,720)	(69,949)	(48,597)
Preferred stock deemed dividend	(8,469)
Net loss allocable to common stockholders	$ (75,189)	$ (69,949)	$ (48,597)
Net loss per share allocable to common stockholders - basic and diluted	$ (0.38)	$ (0.41)	$ (0.39)
Weighted average shares outstanding used to compute basic and diluted net loss per share allocable to common stockholders	196,275	170,469	125,101

Consolidated Statements of Stockholders' Equity - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Preferred Stock	Additional Paid-in Capital	Accumulated Other Comprehensive Income (Loss)	Accumulated Deficit
Beginning Balances at Dec. 31, 2010	$ 52,111	$ 116		$ 369,686	$ (746)	$ (316,945)
Beginning Balances (in shares) at Dec. 31, 2010		115,611
Issuance of common stock upon exercise of stock options and restricted stock awards	10			10
Issuance of common stock upon exercise of stock options and restricted stock awards (In Shares)		308
Issuance of common stock under Employee Stock Purchase Plan	132			132
Issuance of common stock under Employee Stock Purchase Plan (in shares)		106
Proceeds from issuances of common stock and warrants, net of issuance costs	91,298	$ 39		91,259
Proceeds from issuances of common stock and warrants, net of issuance costs (in shares)		38,601
Stock compensation expense	5,189			5,189
Total other comprehensive income (loss)	(263)				(263)
Net loss	(48,597)					(48,597)
Ending Balances at Dec. 31, 2011	99,880	$ 155		466,276	(1,009)	(365,542)
Ending Balances (in shares) at Dec. 31, 2011		154,626
Issuance of common stock upon exercise of stock options and restricted stock awards	1,955	$ 1		1,954
Issuance of common stock upon exercise of stock options and restricted stock awards (In Shares)		1,222
Issuance of common stock under Employee Stock Purchase Plan	307			307
Issuance of common stock under Employee Stock Purchase Plan (in shares)		141
Proceeds from issuances of common stock and warrants, net of issuance costs	71,780	$ 27		71,753
Proceeds from issuances of common stock and warrants, net of issuance costs (in shares)		26,803
Stock compensation expense	10,439			10,439
Total other comprehensive income (loss)	414				414
Net loss	(69,949)					(69,949)
Ending Balances at Dec. 31, 2012	114,826	$ 183		550,729	(595)	(435,491)
Ending Balances (in shares) at Dec. 31, 2012		182,792
Issuance of common stock upon exercise of stock options and restricted stock awards	112			112
Issuance of common stock upon exercise of stock options and restricted stock awards (In Shares)		106
Issuance of common stock under Employee Stock Purchase Plan	224			224
Issuance of common stock under Employee Stock Purchase Plan (in shares)		129
Restricted Stock Award Delivered (in shares)		115
Issuance of common stock, net of issuance costs	80,999	$ 80		80,919
Issuance of common stock, net of issuance costs (in shares)		79,570
Issuance of Series B convertible preferred stock, net of issuance costs	44,209			44,209
Issuance of Series B convertible preferred stock, net of issuance costs (in shares)			43
Beneficial conversion feature of Series B convertible preferred stock
Deemed dividend to holders of Series B convertible preferred stock
Warrants exercised
Warrants exercised (in shares)		84
Stock compensation expense	12,340			12,340
Total other comprehensive income (loss)	447				447
Net loss	(66,720)					(66,720)
Ending Balances at Dec. 31, 2013	186,294	$ 263		688,390	$ (148)	$ (502,211)
Ending Balances (in shares) at Dec. 31, 2013		262,796	43
Initial expenses related to ATM agreement	$ (143)			$ (143)

Consolidated Statements Of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Operating activities
Net loss	$ (66,720)	$ (69,949)	$ (48,597)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	1,327	1,207	1,303
Amortization of intangible assets	0	0	299
Loss (gain) on disposal of property and equipment	18	8	20
Accretion of discounts and amortization of premiums of marketable securities	923	1,298	1,172
Interest associated with long-term note payable to Symphony Dynamo Holdings LLC (“Holdings)		2,190	1,871
Fair value adjustment of the warrant and contingent liabilities to Holdings, including the impact of the anti-dilution provision associated with the common stock and warrants issued to Symphony Capital Partners, L.P. and Symphony Strategic Partners, LLC (collectively, "Symphony")			(843)
Unoccupied facility expense	926
Stock compensation expense	12,340	10,439	5,189
Changes in operating assets and liabilities:
Accounts receivable	(622)	8,522	(8,526)
Prepaid expenses and other current assets	677	(922)	230
Restricted cash and other assets	176	(116)	(290)
Accounts payable	(657)	126	(289)
Accrued liabilities and other long term liabilities	(2,291)	1,916	(2,167)
Deferred revenues	(4,770)	1,472	3,512
Net cash used in operating activities	(58,673)	(43,809)	(47,116)
Investing activities
Purchases of marketable securities	(192,044)	(206,149)	(111,205)
Proceeds from maturities of marketable securities	142,321	169,387	77,729
Purchases of property and equipment, net	(1,629)	(2,931)	(1,142)
Net cash used in investing activities	(51,352)	(39,693)	(34,618)
Financing activities
Proceeds from issuances of common stock	80,856	71,780	91,298
Proceeds from issuances of preferred stock	44,209
Proceeds from issuances of warrants
Proceeds from exercise of stock options and restricted stock awards	112	1,955	10
Proceeds from employee stock purchase plan	224	307	132
Payment of notes payable to Holdings		(15,000)
Net cash provided by financing activities	125,401	59,042	91,440
Effect of exchange rate changes on cash and cash equivalents	147	118	(218)
Net increase (decrease) in cash and cash equivalents	15,523	(24,342)	9,488
Cash and cash equivalents at beginning of year	7,599	31,941	22,453
Cash and cash equivalents at end of year	23,122	7,599	31,941
Non-cash investing and financing activities:
Disposal of fully depreciated property and equipment	86	169	1,181
Net change in unrealized (loss) gain on marketable securities	$ (76)	$ 48	$ 14

Summary of Significant Accounting Policies

12 Months Ended

Dec. 31, 2013

Summary of Significant Accounting Policies

2.	Summary of Significant Accounting Policies

Basis of Presentation

The consolidated financial statements include our accounts and those of our wholly-owned subsidiaries. All significant intercompany accounts and transactions among the entities have been eliminated from the consolidated financial statements.

Liquidity and Financial Condition

We have incurred significant operating losses and negative cash flows from operations since our inception. As of December 31, 2013, we had cash, cash equivalents and marketable securities of $189.4 million. We currently estimate that we have sufficient cash resources to meet our anticipated cash needs through at least the next 12 months based on cash, cash equivalents and marketable securities on hand as of December 31, 2013 and anticipated revenues and funding from existing agreements.

We expect to continue to spend substantial funds in connection with the development and manufacturing of our product candidates, particularly HEPLISAV-B, human clinical trials for our product candidates and additional applications and advancement of our technology. In order to continue these activities, we may need to raise additional funds. This may occur through strategic alliance and licensing arrangements and/or future public or private financings. Sufficient additional funding may not be available on acceptable terms, or at all. If adequate funds are not available in the future, we may need to delay, reduce the scope of or put on hold the HEPLISAV-B program or our other development programs while we seek strategic alternatives.

Use of Estimates

The preparation of financial statements in conformity with U.S. generally accepted accounting principles (“U.S. GAAP”) requires management to make informed estimates and assumptions that affect the amounts reported in the consolidated financial statements and accompanying notes. Actual results may differ materially from these estimates.

Foreign Currency Translation

We consider the local currency to be the functional currency for our international subsidiary, Rhein. Accordingly, assets and liabilities denominated in foreign currencies 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 throughout the year. Currency translation adjustments arising from period to period are charged or credited to accumulated other comprehensive income (loss) in the equity. For the years ended December 31, 2013, 2012 and 2011, we reported an unrealized gain of $0.5 million, an unrealized gain of $0.4 million and an unrealized loss of $0.3 million, respectively. Realized gains and losses resulting from currency transactions are included in the consolidated statements of operations. For the years ended December 31, 2013, 2012 and 2011, we reported a loss of $0.2 million, a loss of $0.2 million and a gain of $0.2 million, respectively, resulting from currency transactions in our consolidated statements of operations.

Cash, Cash Equivalents and Marketable Securities

We consider all highly 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. We invest in short-term money market funds, U.S. government agency securities, U.S. treasury securities and municipal securities. We believe these types of investments are subject to minimal credit and market risk. We do not invest in auction rate securities or securities collateralized by home mortgages, mortgage bank debt, or home equity loans.

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 income (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 investments 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

We operate in one business segment, which is the discovery and development of biopharmaceutical products. We determine our segments based on the way we organize our business by making operating decisions and assessing performance. In fiscal years 2013, 2012 and 2011, 89%, 88% and 94% of our revenues were earned in the United States, respectively, and the remaining revenues were earned in Germany. As of December 31, 2013 and 2012, 9% and 10%, respectively, of our long-lived assets were located in the United States and the remaining long-lived assets were located in Germany.

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 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. government agency securities, U.S. treasury securities and municipal securities. We have not experienced any losses on our cash equivalents and marketable securities.

Accounts receivable are recorded at invoice value. We review our exposure to accounts receivable, including the requirement for allowances based on management’s judgment. We have not historically experienced any significant losses. We do not currently require collateral for any of our accounts receivable.

Our products will require approval from the U.S. Food and Drug Administration (“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 would have a material adverse impact on our business.

We have relied on a limited number of suppliers to produce oligonucleotides for clinical trials and a single contract manufacturer to produce our first generation TLR 9 agonist, 1018 for HEPLISAV-B. The loss of our current supplier would have a significant effect on our ability to produce HEPLISAV-B for commercialization and development of our other product candidates. To date, we have manufactured only small quantities of oligonucleotides and 1018 ourselves for development purposes.

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

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. Repair and maintenance costs are charged to expense as incurred. Leasehold improvements in both of our facilities 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, including intangible 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, long-lived assets are written down to their respective fair values. Fair value is determined primarily using the anticipated cash flows discounted at a rate commensurate with the risk involved. Significant management judgment is required in the forecast of future operating results that are used in the preparation of expected undiscounted cash flows. No impairments of purchased intangible assets have been identified during the years presented.

Goodwill

Our goodwill balance relates to our April 2006 acquisition of Rhein. Goodwill was recorded as the excess purchase price over tangible and intangible assets acquired and liabilities assumed based on their estimated fair value, by applying the acquisition method of accounting. Goodwill is not amortized but is subject to an annual impairment test which consists of a comparison of the fair value of the related reporting unit against its carrying amount including goodwill. If the carrying amount exceeds the fair value, impairment is calculated and 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.

Revenue Recognition

Our revenues consist of amounts earned from collaborations, grants and fees from services and licenses. We enter into license and manufacturing agreements and collaborative research and development arrangements with pharmaceutical and biotechnology partners that may involve multiple deliverables. Our arrangements may include one or more of the following elements: upfront license payments, cost reimbursement for the performance of research and development activities, milestone payments, other contingent payments, contract manufacturing service fees, royalties and license fees. Each deliverable in the arrangement is evaluated to determine whether it meets the criteria to be accounted for as a separate unit of accounting or whether it should be combined with other deliverables. In order to account for the multiple-element arrangements, the Company identifies the deliverables included within the arrangement and evaluates which deliverables represent separate units of accounting. Analyzing the arrangement to identify deliverables requires the use of judgment, and each deliverable may be an obligation to deliver services, a right or license to use an asset, or another performance obligation. We recognize revenue when there is persuasive evidence that an arrangement exists, delivery has occurred or services have been rendered, the price is fixed or determinable and collectability is reasonably assured.

On January 1, 2011, we adopted on a prospective basis Financial Accounting Standards Board (“FASB”) Accounting Standards Update (“ASU”) 2009-13, Multiple-Deliverable Revenue Arrangements, which amends the criteria related to identifying separate units of accounting and provides guidance on whether multiple deliverables exist, how an arrangement should be separated and the consideration allocated.

Non-refundable upfront fees received for license and collaborative agreements entered into prior to January 1, 2011 and other payments under collaboration agreements where we have continuing performance obligations related to the payments are deferred and recognized over our expected performance period. Revenue is recognized on a ratable basis, unless we determine that another method is more appropriate, through the date at which our performance obligations are completed. Management makes its best estimate of the period over which we expect to fulfill our performance obligations, which may include clinical development activities. Given the uncertainties of research and development collaborations, significant judgment is required to determine the duration of the performance period. We recognize cost reimbursement revenue under collaborative agreements as the related research and development costs are incurred, as provided for under the terms of these agreements.

Contingent consideration received for the achievement of a substantive milestone is recognized in its entirety in the period in which the milestone is achieved. A milestone is defined as an event having all of the following characteristics: (i) there is substantive uncertainty at the date the arrangement is entered into that the event will be achieved, (ii) the event can only be achieved based in whole or in part on either the entity’s performance or a specific outcome resulting from the entity’s performance and (iii) if achieved, the event would result in additional payments being due to the entity.

Our license and collaboration agreements with our partners provide for payments to be paid to us upon the achievement of development milestones. Given the challenges inherent in developing biologic products, there is substantial uncertainty whether any such milestones will be achieved at the time we entered into these agreements. In addition, we evaluate whether the development milestones meet the criteria to be considered substantive. The conditions include: (i) the development work is contingent on either of the following: (a) the vendor’s performance to achieve the milestone or (b) the enhancement of the value of the deliverable item or items as a result of a specific outcome resulting from the vendor’s performance to achieve the milestone; (ii) it relates solely to past performance and (iii) it is reasonable relative to all the deliverable and payment terms within the arrangement. As a result of our analysis, we consider our development milestones to be substantive and, accordingly, we expect to recognize as revenue future payments received from such milestones as we achieve each milestone.

Milestone payments that are contingent upon the achievement of substantive at-risk performance criteria are recognized in full upon achievement of those milestone events in accordance with the terms of the agreement and assuming all other revenue recognition criteria have been met. All revenue recognized to date under our collaborative agreements has been nonrefundable.

Our license and collaboration agreements with certain partners also provide for contingent payments to be paid to us based solely upon the performance of our partner. For such contingent payments we expect to recognize the payments as revenue upon receipt, provided that collection is reasonably assured and the other revenue recognition criteria have been satisfied.

Revenues from manufacturing services are recognized upon meeting the criteria for substantial performance and acceptance by the customer.

Revenue from royalty payments is contingent on future sales activities by our licensees. As a result, we recognize royalty revenue when reported by our licensees and when collection is reasonably assured.

Revenue from government and private agency grants are recognized as the related research expenses are incurred and to the extent that funding is approved. Additionally, we recognize revenue based on the facilities and administrative cost rate reimbursable per the terms of the grant awards.

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 such arrangements 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, completion of portions of the clinical trial or similar conditions. Our accruals for clinical trials are 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. The Company makes estimates of its accrued expenses as of each balance sheet date based on the facts and circumstances known to the Company at that time. There have been no material adjustments to the Company’s prior period accrued estimates for clinical trial activities through December 31, 2013.

Stock-Based Compensation

Stock-based compensation expense for stock options and other stock awards is estimated at the grant date based on the award’s fair value-based measurement and is recognized on a straight-line basis over the award’s vesting period, assuming appropriate forfeiture rates. Our determination of the fair value-based measurement 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 highly complex and subjective variables. These variables include, but are not limited to, our expected stock price volatility over the term of the awards, and actual 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-based measurement of stock options granted in the future. Changes in the fair value-based measurement of stock awards could materially impact our operating results.

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 highly subjective and complex assumptions which determine the fair value-based measurement of stock options, including the option’s expected term and the price volatility of the underlying stock. 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 quarter of revision, as well as in the following quarters.

Income Taxes

We account for income taxes using the asset and liability method, under which deferred tax assets and liabilities are determined based on the differences between the financial reporting and tax basis of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to reverse. Additionally, we assess the likelihood that deferred tax assets will be recovered as deductions from future taxable income. We have provided a full valuation allowance on our deferred tax assets at December 31, 2013 and 2012 because we believe it is more likely than not that our deferred tax assets will not be realized as of December 31, 2013, and 2012.

We have no unrecognized tax benefits as of December 31, 2013, including no accrued amounts for interest and penalties. We do not anticipate that total unrecognized tax benefits will significantly change prior to December 31, 2014. Our policy will be to recognize interest and penalties related to income taxes, if any, as a component of general and administrative expense. We are subject to income tax examinations for U.S. federal and state income taxes from 1996 forward. We are subject to tax examination in Germany from 2010 forward.

Recent Accounting Pronouncements

Accounting Standards Update 2013-02

In February 2013, the FASB issued ASU 2013-02, “Reporting of Amounts Reclassified out of Accumulated Other Comprehensive Income.” This ASU expands the presentation of changes in accumulated other comprehensive income. The new guidance requires an entity to disaggregate the total change of each component of other comprehensive income either on the face of the statement of operations or as a separate disclosure in the financial statement footnotes. ASU 2013-02 is effective for fiscal years beginning after December 15, 2012. The Company adopted this guidance on a prospective basis in the first quarter of 2013 and the adoption did not have any impact on our financial position, results of operations or cash flows as there were no amounts reclassified out of accumulated other comprehensive (loss) income during the year ended December 31, 2013.

Fair Value Measurements

12 Months Ended

Dec. 31, 2013

Fair Value Measurements

3.	Fair Value Measurements

The Company defines 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 assumptions.

Recurring Fair Value Measurements

The following table represents the fair value hierarchy for our financial assets (cash equivalents and marketable securities) measured at fair value on a recurring basis as of December 31, 2013 and 2012 (in thousands):

	Level 1		Level 2		Level 3		Total
December 31, 2013
Money market funds	$	20,013	$	-	$	-	$	20,013
U.S. government agency securities		-		167,597		-		167,597
Total	$	20,013	$	167,597	$	-	$	187,610

	Level 1		Level 2		Level 3		Total
December 31, 2012
Money market funds	$	3,140	$	-	$	-	$	3,140
U.S. government agency securities		-		119,233		-		119,233
U.S. treasury securities		-		500		-		500
Municipal securities		-		715		-		715
Total	$	3,140	$	120,448	$	-	$	123,588

Money market funds are highly liquid investments and are actively traded. The pricing information on these investment instruments are 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. Government agency securities, U.S. treasury securities and municipal 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.

- 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 and Marketable Securities

12 Months Ended

Dec. 31, 2013

Cash, Cash Equivalents and Marketable Securities

4.	Cash, Cash Equivalents and Marketable Securities

The following is a summary of cash, cash equivalents and marketable securities as of December 31, 2013, and 2012 (in thousands):

	Amortized Cost		Unrealized Gains		Unrealized Losses			Estimated Fair Value
December 31, 2013
Cash and cash equivalents:
Cash	$	1,766	$	-	$	-		$	1,766
Money market funds		20,013		-		-			20,013
U.S. government agency securities		1,343		-		-			1,343
Total cash and cash equivalents		23,122		-		-			23,122
Marketable securities available-for-sale:
U.S. government agency securities		166,285		16		(47	)		166,254
Total marketable securities available-for-sale		166,285		16		(47	)		166,254
Total cash, cash equivalents and marketable securities	$	189,407	$	16	$	(47	)	$	189,376
December 31, 2012
Cash and cash equivalents:
Cash	$	1,542	$	-	$	-		$	1,542
Money market funds		3,140		-		-			3,140
Municipal securities		715		-		-			715
U.S. government agency securities		2,202		-		-			2,202
Total cash and cash equivalents		7,599		-		-			7,599
Marketable securities available-for-sale:
U.S. government agency securities		116,986		46		(1	)		117,031
U.S. treasury securities		500		-		-			500
Total marketable securities available-for-sale		117,486		46		(1	)		117,531
Total cash, cash equivalents and marketable securities	$	125,085	$	46	$	(1	)	$	125,130

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

	December 31, 2013
	Amortized Cost		Estimated Fair Value
Mature in one year or less	$	93,691	$	93,701
Mature after one year through two years		72,594		72,553
	$	166,285	$	166,254

We invest in short-term money market funds, U.S. government agency securities, U.S treasury securities and municipal securities.

There were no realized gains or losses from the sale of marketable securities in the years ended December 31, 2013, 2012 and 2011. All of our investments are classified as short-term and available-for-sale, as we may not hold our investments until maturity.

Symphony Dynamo, Inc.

12 Months Ended

Dec. 31, 2013

Symphony Dynamo, Inc.

8.	Symphony Dynamo, Inc.

On April 18, 2006, we, Symphony and Holdings entered into a transaction involving a series of related agreements providing for the advancement of certain of our immunostimulatory sequences-based programs for cancer, hepatitis B and hepatitis C therapy (collectively, the “Programs”). Pursuant to these agreements, Symphony formed SDI and invested $50 million to fund the Programs, and we licensed to Holdings our intellectual property rights related to the Programs, which were assigned to SDI. As a result of these agreements, Symphony owned 100% of the equity of Holdings, which owned 100% of the equity of SDI.

In connection with the transaction described above, Holdings granted to us an exclusive purchase option that gave us the right, but not the obligation, to acquire the outstanding equity securities of SDI, which would result in our reacquisition of the intellectual property rights that we licensed to Holdings (the “Original Purchase Option”). In exchange for the Original Purchase Option, we granted Holdings five-year warrants to purchase up to 2,000,000 shares of our common stock at an exercise price of $7.32 per share pursuant to a warrant purchase agreement (the “Original Warrants”), and granted certain registration rights to Holdings pursuant to a registration rights agreement. We also received an exclusive option to purchase either the hepatitis B or hepatitis C therapy program (the “Program Option”) during the first year of the arrangement. In April 2007, we exercised the Program Option for the hepatitis B program which resulted in the recognition of a $15 million liability to Symphony. We remained primarily responsible for the development of the cancer and hepatitis C therapy programs in accordance with a development plan and related development budgets that we agreed to with Holdings.

Prior to the acquisition of all of the outstanding equity of SDI on December 30, 2009, we consolidated the financial position and results of operations of SDI. In November 2009, we entered into an agreement with Holdings to modify the provisions of and to exercise the Original Purchase Option (the “Amended Purchase Option”). We completed the acquisition of all of the outstanding equity of SDI on December 30, 2009. In exchange for all of the outstanding equity of SDI, we issued to Symphony and certain of its co-investors: (i) 13,000,000 shares of common stock (the “Shares”); (ii) 5-year warrants to purchase 2,000,000 shares of common stock with an exercise price of $1.94 per share (the “Warrants”); and (iii) a non-interest bearing note in the principal amount of $15 million, due December 31, 2012, payable in cash, our common stock or a combination thereof at our discretion, which obligation was previously payable solely in cash on April 18, 2011 (the “Note”). In addition, we agreed to contingent cash payments from us 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 the cancer and hepatitis C therapies originally licensed to SDI. The Original Warrants held by Symphony were cancelled as part of this transaction.

We were obligated to make future contingent cash payments to the former Holdings shareholders related to certain payments received by us, if any, from future partnering agreements pertaining to our hepatitis C and cancer therapy programs. We estimated the valuation of this contingent liability using a discounted cash flow model. The discounted cash flow model was derived from management’s assumptions regarding the timing, amounts, and probability of potential upfront and milestone payments for the development and/or commercialization of the hepatitis C program based on transactions for similar stage programs by other companies. These cash flows were discounted at a rate of 16% for the fiscal year ended December 31, 2010.

Changes in the fair value of the contingent consideration liability were recognized in “other income (expense)” in the consolidated statements of operations in the period of the change. During the fiscal year ended December 31, 2010, we reduced the assumed probability of our receipt of upfront and milestone payments from a potential partnership and extended the timing of when these expected receipts would occur. In addition, based on our assumptions regarding our beta and risk free interest rate used in the discounted cash flow model, the change in fair value of the contingent consideration liability resulted in other income of $2.2 million for the fiscal year ended December 31, 2010. During the year ended December 31, 2011, we determined that we would not receive any upfront or milestone payments from a potential partnership for our hepatitis C therapy program and, therefore, estimated the fair value of the liability to be zero as of December 31, 2011 resulting in other income of $0.8 million. These fair value measurements were based on significant inputs not observed in the market and thus represented a Level 3 measurement.

We recorded the acquisition of all of the outstanding equity of SDI pursuant to the Amended Purchase Option as a return of equity to the noncontrolling interest. The acquisition was accounted for as a capital transaction that did not affect our consolidated net loss. However, because the acquisition was accounted for as a capital transaction, the consideration paid in excess of the carrying value of the noncontrolling interest in SDI is treated as a deemed dividend at the time for purposes of reporting net loss and earnings per share.

The estimated fair values of the warrants transferred were calculated using the Black-Scholes valuation model.

We estimated the fair value of the Note using a net present value model with a discount rate of 17%. Imputed interest was recorded as interest expense over the term of the loan using the interest rate method. We paid in cash the $15 million principal balance of the Note on December 31, 2012.

The Shares and Warrants were subject to certain anti-dilution protection in the event that we issued other equity securities within six months from December 30, 2009. As a result of an equity offering completed in April 2010 prior to the expiration of the anti-dilution provision, Symphony received an additional 1,076,420 shares of common stock (“April 2010 Shares”) and warrants to purchase 7,038,210 shares of common stock (“April 2010 Warrants”) having the same terms as the warrants sold in the offering, which have an exercise price of $1.50 per share and a term of five years. The Warrants issued on December 30, 2009 were cancelled upon the issuance of the April 2010 Warrants.

The fair value of the April 2010 Shares and incremental fair value of the April 2010 Warrants provided to Symphony, as measured upon issuance and remeasured at June 30, 2010, resulted in non-operating expense of $11.1 million in the second quarter of 2010. This also resulted in an increase of $9.5 million to the warrant liability and an increase of $1.6 million to additional paid in capital as of June 30, 2010. Following the expiration date of Symphony’s anti-dilution protection, on June 30, 2010, the value of the April 2010 Warrants of $12.0 million was reclassified into stockholders’ equity in the consolidated balance sheets. As of December 31, 2013, warrants to purchase 6,765,128 shares remained outstanding.

Collaborative Research, Development and License Agreements

12 Months Ended

Dec. 31, 2013

Collaborative Research, Development and License Agreements

10.	Collaborative Research, Development and License Agreements

GlaxoSmithKline

In December 2008, we entered into a worldwide strategic alliance with GSK to discover, develop and commercialize TLR inhibitors. Under the terms of the arrangement, we agreed to conduct research and early clinical development in up to four programs: the Lead TLR 7/9 program, a Follow-On TLR 7/9 program, and up to two other TLR programs. In 2011 we began development of a TLR 8 program as one of the two additional programs under the collaboration. GSK subsequently returned all rights to this program to us.

We are currently conducting a Phase 1 clinical trial in the Lead TLR 7/9 program with DV1179 in systemic lupus erythematosus patients. The Company is not currently performing any activities on the Follow-On TLR 7/9 program. GSK has not yet chosen to initiate development of the remaining program under the agreement. In December 2013, we amended our agreement with GSK to extend the research term until conclusion of the ongoing phase 1 study of DV1179. In addition, the exclusivity provisions of the agreement were modified, giving us rights to immediately begin preclinical and clinical research on inhibitors of TLR 7 and 9 (other than DV1179) for oncology indications.

GSK can exercise its exclusive option to license each program. If GSK exercises an option, GSK would carry out further development and commercialization of the corresponding products. If GSK exercises their option on the Lead TLR 7/9 program, then we are eligible to receive payments of up to approximately $125 million, comprised of contingent option exercise payments and additional payments based on GSK’s achievement of certain development, regulatory and commercial objectives.

We are also eligible to receive up to $60 million if aggregate worldwide annual net sales milestones are achieved and tiered royalties ranging from the mid–single digit to mid-teens on sales of any products originating from the collaboration. We have retained an option to co-develop and co-promote one product under this agreement.

We received an initial payment of $10 million in 2008. The deliverables under this arrangement did not have stand-alone value and so did not qualify as separate units of accounting. In 2011, we earned and recognized $12 million in substantive development milestone payments related to the initiation of Phase I and proof-of-mechanism clinical trials of DV1179 in systemic lupus erythematosus patients. In 2011, we earned and recognized $3 million in substantive development milestone payments related to the initiation of development of the TLR 8 program.

Revenue from the initial payment from GSK was deferred and is being recognized over the expected period of performance under the agreement, initially estimated to be seven years. In the fourth quarter of 2013 we reevaluated and revised the expected period of performance under the agreement from seven years to six years resulting in the recognition of $0.3 million of additional revenue in 2013.

The following table summarizes the revenues recognized under our agreement with GSK (in thousands):

	Year ended December 31,
	2013		2012		2011
Initial payment	$	1,702	$	1,428	$	1,428
Milestone revenue		-		-		15,000
Total	$	1,702	$	1,428	$	16,428

As of December 31, 2013 and 2012, deferred revenue relating to the initial payment was $2.5 million and $4.2 million, respectively.

Absent early termination, the agreement will expire when all of GSK’s payment obligations expire. Either party may terminate the agreement early upon written notice if the other party commits an uncured material breach of the agreement. Either party may terminate the agreement in the event of insolvency of the other party. GSK also has the option to terminate the agreement without cause upon prior written notice within a specified window of time dependent upon the stage of clinical development of the programs.

AstraZeneca

In September 2006, we entered into a three-year research collaboration and license agreement with AstraZeneca for the discovery and development of TLR 9 agonist-based therapies for the treatment of asthma and chronic obstructive pulmonary disease.

In October 2011, we amended our agreement with AstraZeneca to provide that we will conduct initial clinical development of AZD 1419. Under the terms of the amended agreement, AstraZeneca will fund all program expenses to cover the cost of development activities through Phase 2a, estimated to total approximately $20 million. We received an initial payment of $3 million to begin the clinical development program. In the first quarter of 2012, we received a $2.6 million payment to advance AZD1419 into preclinical toxicology studies and these toxicology studies were completed in the third quarter of 2012. We and AstraZeneca have agreed to advance AZD 1419 towards a Phase 1 clinical trial, which resulted in a development funding payment of $6 million, received in the fourth quarter of 2012. If AstraZeneca chooses to advance the program following completion of Phase 2a, we will receive a $20 million milestone payment and AstraZeneca will retain its rights to develop the candidate therapy and to commercialize the resulting asthma product. We are eligible to receive additional milestone payments, which we have determined to be substantive milestones, of up to approximately $100 million, based on the achievement of certain development and regulatory objectives. Additionally, upon commercialization, we are eligible to receive tiered royalties ranging from the mid to high single-digits based on product sales of any products originating from the collaboration. We have the option to co-promote in the United States products arising from the collaboration, if any. AstraZeneca has the right to sublicense its rights upon our prior consent.

Revenue from the initial payment was deferred and is being recognized over the expected period of performance under the agreement, which is approximately 50 months. Revenue from the development funding payment is being recognized as the development work is performed.

The following table summarizes the revenues earned under our agreement with AstraZeneca (in thousands):

	Year ended December 31,
	2013		2012		2011
Initial payments	$	720	$	720	$	120
Performance of research activities		2,507		2,462		642
Total	$	3,227	$	3,182	$	762

As of December 31, 2013 and 2012, total deferred revenue from the initial payment and development funding payments was $4.8 million and $7.7 million, respectively.

Absent early termination, the agreement will expire when all of AstraZeneca’s payment obligations expire. AstraZeneca has the right to terminate the agreement at any time upon prior written notice and either party may terminate the agreement early upon written notice if the other party commits an uncured material breach of the agreement.

National Institutes of Health (“NIH”) and Other Funding

We have been awarded various grants from the NIH and the NIH’s National Institute of Allergy and Infectious Disease (“NIAID”) in order to fund research. The awards are related to specific research objectives and we earn revenue as the related research expenses are incurred. We have earned revenue during the periods ended December 31, 2013 and 2012 from the following awards:

·	September 2013, NIH awarded us $0.2 million to fund research in developing TLR antagonists for therapy of hepatic fibrosis and cirrhosis.

·	June 2012, NIH awarded us $0.6 million to fund research in screening for inhibitors of TLR 8 for treatment of autoimmune diseases.

·	May 2012, NIH awarded us $0.4 million to fund development of TLR 8 inhibitors for treatment of rheumatoid arthritis.

·	July 2011, NIH awarded us $0.6 million to fund research in preclinical models of skin autoimmune inflammation.

August 2010, NIAID awarded us a grant to take a systems biology approach to study the differences between individuals who do or do not respond to vaccination against the hepatitis B virus. This study will be one of several projects conducted under a grant to the Baylor Institute of Immunology Research in Dallas as part of the Human Immune Phenotyping Centers program. We have been awarded a total of $1.4 million under this grant.

·	July 2010, NIH awarded us $0.6 million to explore the feasibility of developing a universal vaccine to prevent infection by human papilloma virus.

·	September 2008, NIAID awarded us a five-year $17 million contract to develop our oligonucleotide technology using TLR 9 agonists as vaccine adjuvants. The contract supports adjuvant development for anthrax as well as other disease models.

The following table summarizes the revenues recognized under the various arrangements with the NIH and NIAID (in thousands):

	Year ended December 31,
	2013		2012		2011
NIAID contracts	$	4,103	$	3,571	$	2,730
All other NIH contracts		1,035		368		380
Total grant revenue	$	5,138	$	3,939	$	3,110

Net Loss Per Share

12 Months Ended

Dec. 31, 2013

Net Loss Per Share

11.	Net Loss Per Share

Basic net loss per share allocable to common stockholders is calculated by dividing the net loss allocable to common stockholders by the weighted-average number of common shares outstanding during the period. Diluted net loss per share allocable to common stockholders is computed by dividing the net loss allocable to common stockholders 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, common stock subject to repurchase by us, 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 allocable to common stockholders when their effect is dilutive.

	December 31,
	2013			2012			2011
Basic and diluted net loss per share (in thousands, except per share amounts):
Numerator:
Net loss		(66,720	)		(69,949	)		(48,597	)
Preferred stock deemed dividend		(8,469	)		-			-
Net loss allocable to common stockholders	$	(75,189	)	$	(69,949	)	$	(48,597	)
Denominator for basic and diluted net loss per share allocable to common stockholders:
Weighted-average common shares outstanding		196,275			170,469			125,101
Basic and diluted net loss per share allocable to common stockholders	$	(0.38	)	$	(0.41	)	$	(0.39	)

Outstanding warrants, stock options, Series B Convertible Preferred Stock and stock subject to repurchase by us under stock awards were excluded from the calculation of net loss per share allocable to common stockholders as the effect of their inclusion would have been anti-dilutive.

	December 31,
	2013		2012		2011
Outstanding securities not included in diluted net loss per share calculation (in thousands):
Stock options and stock awards		17,040		15,561		11,101
Series B Convertible Preferred Stock (as converted to common stock)		43,430		-		-
Warrants		12,464		12,714		25,729
		72,934		28,275		36,830

Preferred Stock, Common Stock and Warrants

12 Months Ended

Dec. 31, 2013

Preferred Stock, Common Stock and Warrants

12.	Preferred Stock, Common Stock and Warrants

Authorized Shares

On May 29, 2013 the stockholders approved an increase in the number of authorized shares of common stock from 250,000,000 to 350,000,000. The increase in authorized shares was effected pursuant to a Certificate of Amendment to the Sixth Amended and Restated Certificate of Incorporation (the "Certificate of Amendment"), filed with the Secretary of State of the State of Delaware on May 30, 2013

Preferred Stock Outstanding

As of December 31, 2013 there were 5,000,000 shares of preferred stock authorized and no shares outstanding.

In October 2013 the Company sold 43,430 shares of $0.001 par value Series B Convertible Preferred Stock for a purchase price of $1,075 per share and gross proceeds of approximately $46.7 million in an underwritten public offering. After issuance costs of approximately $2.5 million, the net proceeds from the offering were approximately $44.2 million.

Each share of Series B Convertible 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 Convertible Preferred Stock into shares of common stock if, as a result of such conversion, the holder and its affiliates would own more than 9.98% of the total number of shares of common stock then issued and outstanding. In the event of the Company’s liquidation, dissolution, or winding up, holders of Series B Convertible Preferred Stock will receive a payment equal to $0.001 per share before any proceeds are distributed to the common stockholders. Shares of Series B Convertible 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 Convertible Preferred Stock is required to amend the terms of the Series B Convertible Preferred Stock. Holders of Series B Convertible Preferred Stock are not entitled to receive any dividends, unless and until specifically declared by the Company’s board of directors. The Series B Convertible Preferred Stock ranks senior to the Company’s common stock as to distributions of assets upon the Company’s liquidation, dissolution or winding up, whether voluntarily or involuntarily. The Series B Convertible Preferred Stock may rank senior to, on parity with or junior to any class or series of the Company’s 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 Convertible Preferred Stock is convertible exceeded the allocated purchase price of the Series B Convertible Preferred Stock by $8.5 million on the date of issuance, for which the Company recorded a deemed dividend. The Company recognized the deemed dividend equal to the number of shares of Series B Convertible Preferred Stock sold on October 30, 2013 multiplied by the difference between the value of the common stock and the Series B Convertible Preferred Stock conversion price per share on that date. The dividend was reflected as a one-time, non-cash, deemed dividend to the holders of Series B Convertible Preferred Stock on the date of issuance, which is the date the stock first became convertible.

Preferred Stock Rights

On November 4, 2008, our Board of Directors declared a dividend of one preferred share purchase right (a “Right”) for each outstanding share of our Common Stock, par value $0.001 per share (the “Common Shares”). The dividend was payable on November 17, 2008 to the stockholders of record on that date. Each Right entitles the registered holder to purchase from us one one-hundredth of a share of Series A Junior Participating Preferred Stock, par value $0.001 per share (the “Preferred Shares”), at a price of $6.00 per one one-hundredth of a Preferred Share, subject to adjustment. Upon the acquisition of, or announcement of the intent to acquire, 20 percent or more of our outstanding Common Shares by a person, entity or group of affiliated or associated persons (“Acquiring Person”), each holder of a Right, other than Rights held by the Acquiring Person, will have the right to purchase that number of Common Shares having a market value of two times the exercise price of the Right. If we are acquired in a merger or other business combination transaction or 50 percent or more of our assets or earning power are sold to an Acquiring Person, each holder of a Right will thereafter have the right to purchase, at the then current exercise price of the Right, that number of shares of common stock of the acquiring company which at the time of such transaction will have a market value of two times the exercise price of the Right. The Rights plan is intended to maximize the value of the Company in the event of an unsolicited attempt to take over the Company in a manner or on terms not approved by the Company’s Board of Directors. The Rights will expire on November 17, 2018, unless the Rights are earlier redeemed or exchanged by the Company.

Common Stock Outstanding

In October 2013 we completed an underwritten public offering of 79,570,000 shares of our common stock to the public at $1.075 per share. The gross proceeds to us from this offering were approximately $85.5 million. After deducting issuance costs of approximately $4.5 million, the net proceeds from the offering were approximately $80.9 million.

On March 29, 2013, we entered into an At Market Issuance Sales Agreement (the “Agreement”) with MLV & Co. LLC (“MLV”) under which we may offer and sell our common stock having aggregate sales proceeds of up to $50,000,000 from time to time through MLV as our sales agent. Sales of our common stock through MLV, if any, will be made by means of ordinary brokers’ transactions on the NASDAQ Capital Market or otherwise at market prices prevailing at the time of sale, in block transactions, or as otherwise agreed upon by us and MLV. MLV will use commercially reasonable efforts to sell our common stock from time to time, based upon instructions from us (including any price, time or size limits or other customary parameters or conditions we may impose). We will pay MLV a commission of up to 3.0% of the gross sales proceeds of any common stock sold through MLV under the Agreement. No sales of our common stock have taken place under this Agreement as of December 31, 2013.

On May 9, 2012, we completed an underwritten public offering of 17,500,000 shares of our common stock to the public at $4.25 per share. The net proceeds to us from this offering were $69.6 million, after deducting offering expenses.

On November 3, 2011, we completed an underwritten public offering of 27,600,000 shares of our common stock including 3,600,000 shares sold pursuant to the full exercise of an overallotment option previously granted to the underwriters at a price to the public of $2.50 per share. The net proceeds to us from this offering were $64.5 million, after deducting offering expenses.

On November 2, 2010, we completed an underwritten public offering of 26,450,000 shares of our common stock including 3,450,000 shares sold pursuant to the full exercise of an overallotment option previously granted to the underwriters at a price to the public of $1.70 per share. The net proceeds to us from this offering were $42.0 million, after deducting offering expenses.

On September 20, 2010, we entered into a Purchase Agreement with Aspire Capital, which provided that, upon the terms and subject to the conditions and limitations set forth therein, Aspire Capital was committed to purchase up to an aggregate of $30.0 million of shares of our common stock (the “Purchase Shares”) over the 25-month term of the Purchase Agreement. Under the Purchase Agreement, we agreed to pay Aspire Capital a commitment fee equal to 4% of $30 million in consideration for Aspire Capital’s obligation to purchase up to $30 million of our common stock. We paid this commitment fee of $1.2 million by the issuance of 600,000 shares of our common stock and this fee was recorded as a cost of raising capital and netted against the gross proceeds from the Purchase Agreement in September 2010. During 2010, we sold 2,350,000 shares of common stock to Aspire Capital for $3.3 million and during 2011 we sold 10,995,210 shares of common stock for $26.7 million, which totaled the proceeds available to us of $30 million under the Purchase Agreement.

On April 16, 2010, we completed an underwritten public offering resulting in net proceeds of $41.1 million, after deducting offering expenses of approximately $3.0 million, from the sale of 30,293,000 units at a per unit price of $1.4525. Each unit consisted of one share of common stock and one warrant to purchase 0.5 of a share of common stock. Each warrant has an exercise price of $1.50 per share, and is exercisable for a period of five years from the date of issuance. From this offering, warrants to purchase an aggregate of 10,913,873 shares of our common stock were outstanding as of December 31, 2013 (including the warrants to purchase 6,765,128 shares provided to Symphony as described in Note 8 “Symphony Dynamo, Inc.”).

Warrants

In connection with a 2007 loan agreement that was subsequently terminated in 2008, we issued warrants to purchase up to 3,550,000 shares of our common stock as follows:

Warrant Issuance Date	Shares Issuable (in thousands)		Expiration Date	Exercise Price per Share		Outstanding as of December 31, 2013 (in thousands)
July 18, 2007		1,250	2/26/2014	$	5.13		1,250
October 18, 2007		1,300	2/26/2014	$	1.68		-
December 27, 2007		300	2/26/2014	$	5.65		300
December 27, 2007		700	2/26/2014	$	1.68		-
Total		3,550					1,550

As of December 31, 2013, warrants to purchase an aggregate of approximately 12,500,000 shares of our common stock were outstanding. The warrants are exercisable at a weighted average price of $1.96 per share. During the years ended December 31, 2013, and 2012, warrants were exercised to purchase an aggregate of approximately 250,000 and 13,000,000 shares, respectively, of our common stock.

- Definition

The entire disclosure for shareholders' equity comprised of portions attributable to the parent entity and noncontrolling interest, including other comprehensive income. Includes, but is not limited to, balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings, accumulated balance for each classification of other comprehensive income and amount of comprehensive income.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(d),(e))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21484-112644

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB TOPIC 4.E)
-URI http://asc.fasb.org/extlink&oid=27010918&loc=d3e74512-122707

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21488-112644

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+ Details

Equity Plans and Stock-Based Compensation

12 Months Ended

Dec. 31, 2013

Equity Plans and Stock-Based Compensation

13.	Equity Plans and Stock-Based Compensation

Stock Plans

As of December 31, 2013, we had three share-based compensation plans.

2004 Stock Incentive Plan (“2004 Plan”)

The 2004 Plan was adopted in January 2004 by the Board of Directors and stockholders and became effective on February 11, 2004. This plan provided for the issuance of up to 3,500,000 shares of our common stock plus an annual increase. Subsequently, we discontinued granting stock options under the 1997 Plan. Options under the 2004 Plan were granted for periods of up to ten years and the exercise price of all stock options granted under the 2004 Plan was at least equal to 100% of the fair market value of the common stock on the date of grant. If, however, incentive stock options were granted to an employee who owns stock possessing more than 10% of the voting power of all classes of the Company’s stock or the stock of any parent or subsidiary of the Company, the exercise price of any incentive stock option granted must equal at least 110% of the fair market value on the grant date and the maximum term of these incentive stock options must not exceed five years. The maximum term of an incentive stock option granted to any other participant must not exceed ten years. The 2004 Plan authorizes the issuance of various forms of stock-based awards including stock options, restricted stock, restricted stock units and other equity awards to employees, consultants and members of the board of directors. As of December 31, 2013, options to purchase 4,066,277 shares of common stock remained outstanding under the 2004 Plan.

2010 Employment Inducement Award Plan (“Inducement Plan”)

The Inducement Plan was adopted in January 2010 by our Board of Directors to induce qualified individuals to join Dynavax. This Inducement Plan provided for the issuance of up to 1,500,000 shares of our common stock and became effective on January 8, 2010. Stockholder approval of the Inducement Plan is not required under NASDAQ Marketplace Rule 5635(c)(4). As of December 31, 2013, options to purchase 743,625 shares of common stock remained outstanding under the Inducement Plan.

2011 Equity Incentive Plan (“2011 Plan”)

The 2011 Plan was approved by the Company’s stockholders and adopted in January 2011. On May 29, 2013, the stockholders of the Company approved an amendment to the 2011 Plan to increase the number of shares of common stock authorized for issuance under the plan by 10,000,000. The 2011 Plan, as amended, provides for the issuance of up to 25,000,000 shares of our common stock to employees and non-employees of the Company and became effective on January 6, 2011. The 2011 Plan is administered by our Board of Directors, or a designated committee of the Board of Directors, and awards granted under the 2011 Plan have a term of 10 years unless earlier terminated by the Board of Directors. After the adoption of the 2011 Plan, no additional awards were granted under either the 2004 Plan or the Inducement Plan. As of January 6, 2011, all shares subject to awards outstanding under the 2004 Plan and Inducement Plan that expire or are forfeited will be included in the reserve for the 2011 Plan to the extent such shares would otherwise return to such plans. As of December 31, 2013, options to purchase 10,954,940 shares of common stock remained outstanding under the 2011 Plan. As of December 31, 2013, there were 13,666,964 shares of common stock reserved for issuance under the 2011 Plan.

Activity under our stock plans is set forth below:

	Shares Underlying Outstanding Options (in thousands)			Weighted-Average Exercise Price Per Share (in thousands)		Weighted-Average Remaining Contractual Term (years)		Aggregate Intrinsic Value
Balance at December 31, 2012		13,806		$	3.38
Options granted		5,614			2.69
Options exercised		(131	)		1.43
Options cancelled:
Options forfeited (unvested)		(2,555	)		3.31
Options cancelled (vested)		(969	)		3.34
Balance at December 31, 2013		15,765			3.17		5.26	$	1,427
Vested and expected to vest at December 31, 2013		15,765			3.17		5.26	$	1,427
Exercisable at December 31, 2013		10,628			3.36		3.61	$	1,289

The total intrinsic value of stock options exercised during the years ended December 31, 2013, 2012 and 2011 was, $0.3 million, $2.7 million and $0.1 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, 2013, 2012 and 2011 was, $12.1 million, $9.6 million and $2.8 million, respectively.

Our non-vested stock awards are comprised of restricted stock units granted with performance-based vesting criteria. A summary of the status of non-vested restricted stock units as of December 31, 2013, and activities during 2013 is summarized as follows:

	Number of Shares (In thousands)			Weighted-Average Grant-Date Fair Value
Non-vested as of December 31, 2012		1,755		$	4.23
Granted		250		$	1.23
Vested		(115	)	$	1.10
Forfeited or expired		(615	)	$	4.23
Non-vested as of December 31, 2013		1,275		$	3.93

Stock-based compensation expense related to restricted stock units was approximately $0.1 million for the year ended December 31, 2013. The aggregate intrinsic value of the restricted stock units outstanding as of December 31, 2013, based on our stock price on that date, was $2.5 million.

The weighted average grant-date fair value of restricted stock units granted during the years ended December 31, 2013 and 2012 was, $1.23 and $4.23, respectively. No restricted stock units were granted during 2011. The total fair value of restricted stock units vested during the years ended December 31, 2013, 2012, and 2011 was, $0.1 million, $0.2 million, and $0.8 million, respectively.

Stock-Based Compensation

Under our stock-based compensation plans, option awards generally vest over a four-year period contingent upon continuous service and expire 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 under the 2011 Plan, the 2004 Plan and the Inducement Plan. As of December 31, 2013, 2,047,466 shares were outstanding related to options and restricted stock units subject to these performance-based vesting criteria. 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,
	2013			2012			2011			2013			2012			2011
Weighted-average fair value	$	2.41		$	3.30		$	2.76		$	0.93		$	3.54		$	2.09
Risk-free interest rate		1.1	%		0.5	%		1.3	%		0.2	%		0.2	%		0.3	%
Expected life (in years)		5.9			4.2			4.0			1.3			1.1			1.2
Volatility		1.4			1.6			1.6			0.8			1.6			1.6

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, while giving consideration to options that have not yet completed a full life cycle. 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. 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.

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

	Year Ended December 31,
	2013		2012		2011
Employees and directors stock-based compensation expense	$	11,828	$	10,439	$	5,185
Non-employees stock-based compensation expense		512		-		4
Total	$	12,340	$	10,439	$	5,189

	Year Ended December 31,
	2013		2012		2011
Research and development	$	4,228	$	3,514	$	2,103
General and administrative		8,112		6,925		3,086
Total	$	12,340	$	10,439	$	5,189

Stock based compensation expense recognized in 2013 and 2012 includes $4.9 million related to employee severance arrangements and $0.5 million for awards to non-employees for the year ended December 31, 2013 and $1.5 million related to employee severance arrangements for the same period in 2012. During the year ended December 31, 2013, we recognized $1.3 million in additional stock-based compensation expense due to the modification of the terms of stock options for five employees. During the year ended December 31, 2012, we recognized $0.7 million in additional stock-based compensation expense due to the modification of the terms of stock options for one employee.

As of December 31, 2013, the total unrecognized compensation cost related to non-vested stock options deemed probable of vesting, including all stock options with time-based vesting, net of estimated forfeitures, amounted to $10.3 million, which is expected to be recognized over the remaining weighted-average vesting period of 2.8 years. As of December 31, 2013, the total unrecognized compensation cost related to non-vested stock options not deemed probable of vesting, net of estimated forfeitures, amounted to $3.8 million.

As of December 31, 2013, the total unrecognized compensation cost related to shares of our common stock under the Purchase Plan, amounted to $0.1 million, which is expected to be recognized over the remaining weighted-average vesting period of 1.4 years.

Employee Stock Purchase Plan

In January 2004, the Board of Directors and stockholders adopted the 2004 Employee Stock Purchase Plan (the “Purchase Plan”). The Purchase Plan provides for the purchase of common stock by eligible employees and became effective on February 11, 2004. 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 offer period (generally, the fifteenth 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 fourteenth day in February or August).

As of December 31, 2013, 996,000 shares were approved for issuance under the Purchase Plan, subject to adjustment for a stock split, or any future stock dividend or other similar change in our common stock or capital structure. To date, employees have acquired 828,414 shares of our common stock under the Purchase Plan. As of December 31, 2013, 167,586 shares of our common stock remained available for future purchases.

Income Taxes

12 Months Ended

Dec. 31, 2013

Income Taxes

15.	Income Taxes

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

	Year Ended December 31,
	2013			2012			2011
U.S.	$	(67,004	)	$	(70,792	)	$	(49,990	)
Non U.S.		284			843			1,393
Total	$	(66,720	)	$	(69,949	)	$	(48,597	)

No income tax expense was recorded for the years ended December 31, 2013, 2012 and 2011 due to net operating loss carryforwards to offset the net income at Dynavax Europe and a valuation allowance which offsets the deferred tax assets. 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,
	2013			2012			2011
Income tax benefit at federal statutory rate	$	(22,678	)	$	(23,650	)	$	(16,523	)
State tax		(178	)		(89	)		(2,586	)
Business credits		(2,515	)		-			(1,394	)
Deferred compensation charges		3,072			1,002			595
Change in valuation allowance		22,354			21,966			18,099
Change in foreign tax rates		-			-			(34	)
Change in the fair value measurements		-			-			286
Non-deductible debt discount		-			-			509
Deemed dividend		-			-			273
Prior year true up		-			-			-
Other		(55	)		771			775
Total income tax expense	$	-		$	-		$	-

Deferred tax assets and liabilities as of December 31, 2013 and 2012 consisted of the following (in thousands):

	December 31,
	2013			2012
Deferred tax assets:
Net operating loss carry forwards	$	147,655		$	127,529
Research tax credit carry forwards		21,336			18,163
Accruals and reserves		9,501			8,529
Capitalized research costs		10,662			12,757
Deferred revenue		2,486			2,180
Other		1,222			1,221
		192,862			170,379
Less valuation allowance		(192,733	)		(170,232	)
Total deferred tax assets		129			147
Deferred tax liabilities:
Fixed Assets		(162	)		(86	)
Other		33			(61	)
Total deferred tax liabilities		(129	)		(147	)
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 $22.5 million, $22.0 million and $18.1 million during the years ended December 31, 2013, 2012 and 2011, respectively. The amount of the valuation allowance for deferred tax assets associated with excess tax deductions from stock based compensation arrangements that will be allocated to contributed capital if the future tax benefits are subsequently recognized is $0.3 million.

We have not recorded deferred income taxes applicable to undistributed earnings of a foreign subsidiary that are indefinitely reinvested in foreign operations. Generally, such earnings become subject to U.S. tax upon the remittance of dividends and under certain other circumstances. It is not practicable to estimate the amount of the deferred tax liability on such undistributed earnings.

As of December 31, 2013, we had federal net operating loss carryforwards of approximately $384.1 million, which will expire in the years 2018 through 2037 and federal research and development tax credits of approximately $13.8 million, which expire in the years 2018 through 2033.

As of December 31, 2013, we had potential net operating loss carryforwards for California state income tax purposes of approximately $219.7 million, which expire in the years 2013 through 2033, and California state research and development tax credits of approximately $11.5 million which do not expire.

As of December 31, 2013, we had net operating loss carryforwards for foreign income tax purposes of approximately $27.8 million, which do not expire.

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 the Company has a change in ownership, as defined, the annual utilization of such carryforwards could be limited. Due to past equity issuances and changes in ownership of Dynavax common stock, we believe that our ability to use some of our net operating losses and tax credits in the future may be limited.

Selected Quarterly Financial Data

12 Months Ended

Dec. 31, 2013

Selected Quarterly Financial Data

16.	Selected Quarterly Financial Data (Unaudited; in thousands, except per share amounts)

	Year Ended December 31, 2013
	Q1			Q2			Q3			Q4
Revenues	$	2,085		$	3,392		$	2,927		$	2,847
Net loss	$	(20,825	)	$	(17,164	)	$	(15,675	)	$	(13,056	)
Net loss allocable to common stockholders	$	(20,825	)	$	(17,164	)	$	(15,675	)	$	(21,525	)
Basic and diluted net loss per share allocable to common stockholders	$	(0.11	)	$	(0.09	)	$	(0.09	)	$	(0.09	)
Shares used to compute basic and diluted net loss per share allocable to common stockholders		182,847			182,913			183,022			235,879

	Year Ended December 31, 2012
	Q1			Q2			Q3			Q4
Revenues	$	2,350		$	2,684		$	2,874		$	1,806
Net loss	$	(16,505	)	$	(15,110	)	$	(17,791	)	$	(20,543	)
Net loss allocable to common stockholders	$	(16,505	)	$	(15,110	)	$	(17,791	)	$	(20,543	)
Basic and diluted net loss per share allocable to common stockholders	$	(0.11	)	$	(0.09	)	$	(0.10	)	$	(0.11	)
Shares used to compute basic and diluted net loss per share allocable to common stockholders		155,431			167,697			177,870			180,685

Summary of Significant Accounting Policies (Policies)

12 Months Ended

Dec. 31, 2013

Basis of Presentation

Liquidity and Financial Condition

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 investments 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

Long-Lived Assets

Goodwill

Revenue Recognition

Revenues from manufacturing services are recognized upon meeting the criteria for substantial performance and acceptance by the customer.

Research and Development Expenses and Accruals

Stock-Based Compensation

Income Taxes

Recent Accounting Pronouncements

Accounting Standards Update 2013-02

Fair Value Measurements (Tables)

12 Months Ended

Dec. 31, 2013

Fair Value Hierarchy For Financial Assets And Liabilities Measured At Fair Value On Recurring Basis

	Level 1		Level 2		Level 3		Total
December 31, 2013
Money market funds	$	20,013	$	-	$	-	$	20,013
U.S. government agency securities		-		167,597		-		167,597
Total	$	20,013	$	167,597	$	-	$	187,610

	Level 1		Level 2		Level 3		Total
December 31, 2012
Money market funds	$	3,140	$	-	$	-	$	3,140
U.S. government agency securities		-		119,233		-		119,233
U.S. treasury securities		-		500		-		500
Municipal securities		-		715		-		715
Total	$	3,140	$	120,448	$	-	$	123,588

Cash, Cash Equivalents and Marketable Securities (Tables)

12 Months Ended

Dec. 31, 2013

Summary of Cash, Cash Equivalents and Marketable Securities

The following is a summary of cash, cash equivalents and marketable securities as of December 31, 2013, and 2012 (in thousands):

	Amortized Cost		Unrealized Gains		Unrealized Losses			Estimated Fair Value
December 31, 2013
Cash and cash equivalents:
Cash	$	1,766	$	-	$	-		$	1,766
Money market funds		20,013		-		-			20,013
U.S. government agency securities		1,343		-		-			1,343
Total cash and cash equivalents		23,122		-		-			23,122
Marketable securities available-for-sale:
U.S. government agency securities		166,285		16		(47	)		166,254
Total marketable securities available-for-sale		166,285		16		(47	)		166,254
Total cash, cash equivalents and marketable securities	$	189,407	$	16	$	(47	)	$	189,376
December 31, 2012
Cash and cash equivalents:
Cash	$	1,542	$	-	$	-		$	1,542
Money market funds		3,140		-		-			3,140
Municipal securities		715		-		-			715
U.S. government agency securities		2,202		-		-			2,202
Total cash and cash equivalents		7,599		-		-			7,599
Marketable securities available-for-sale:
U.S. government agency securities		116,986		46		(1	)		117,031
U.S. treasury securities		500		-		-			500
Total marketable securities available-for-sale		117,486		46		(1	)		117,531
Total cash, cash equivalents and marketable securities	$	125,085	$	46	$	(1	)	$	125,130

Maturities of Marketable Securities Available-for-Sale

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

	December 31, 2013
	Amortized Cost		Estimated Fair Value
Mature in one year or less	$	93,691	$	93,701
Mature after one year through two years		72,594		72,553
	$	166,285	$	166,254

- Definition

Tabular disclosure of available-for-sale securities which includes, but is not limited to, changes in the cost basis and fair value, fair value and gross unrealized gain (loss), fair values by type of security, contractual maturity and classification, amortized cost basis, contracts to acquire securities to be accounted for as available-for-sale, debt maturities, transfers to trading, change in net unrealized holding gain (loss) net of tax, continuous unrealized loss position fair value, aggregate losses qualitative disclosures, other than temporary impairment (OTTI) losses or other disclosures related to available for sale securities.

+ References + Details

Collaborative Research and Development Agreements (Tables)

12 Months Ended

Dec. 31, 2013

Agreement With Gsk

Summary of Revenues Recognized by Major Customer

The following table summarizes the revenues recognized under our agreement with GSK (in thousands):

	Year ended December 31,
	2013		2012		2011
Initial payment	$	1,702	$	1,428	$	1,428
Milestone revenue		-		-		15,000
Total	$	1,702	$	1,428	$	16,428

Astra Zeneca

Summary of Revenues Recognized by Major Customer

The following table summarizes the revenues earned under our agreement with AstraZeneca (in thousands):

	Year ended December 31,
	2013		2012		2011
Initial payments	$	720	$	720	$	120
Performance of research activities		2,507		2,462		642
Total	$	3,227	$	3,182	$	762

National Institutes of Health

Summary of Revenues Recognized by Major Customer

The following table summarizes the revenues recognized under the various arrangements with the NIH and NIAID (in thousands):

	Year ended December 31,
	2013		2012		2011
NIAID contracts	$	4,103	$	3,571	$	2,730
All other NIH contracts		1,035		368		380
Total grant revenue	$	5,138	$	3,939	$	3,110

Net Loss Per Share (Tables)

12 Months Ended

Dec. 31, 2013

Computation of Basic and Diluted Earnings Per Share

	December 31,
	2013			2012			2011
Basic and diluted net loss per share (in thousands, except per share amounts):
Numerator:
Net loss		(66,720	)		(69,949	)		(48,597	)
Preferred stock deemed dividend		(8,469	)		-			-
Net loss allocable to common stockholders	$	(75,189	)	$	(69,949	)	$	(48,597	)
Denominator for basic and diluted net loss per share allocable to common stockholders:
Weighted-average common shares outstanding		196,275			170,469			125,101
Basic and diluted net loss per share allocable to common stockholders	$	(0.38	)	$	(0.41	)	$	(0.39	)

	December 31,
	2013		2012		2011
Outstanding securities not included in diluted net loss per share calculation (in thousands):
Stock options and stock awards		17,040		15,561		11,101
Series B Convertible Preferred Stock (as converted to common stock)		43,430		-		-
Warrants		12,464		12,714		25,729
		72,934		28,275		36,830

Equity Plans and Stock-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2013

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 (in thousands)		Weighted-Average Remaining Contractual Term (years)		Aggregate Intrinsic Value
Balance at December 31, 2012		13,806		$	3.38
Options granted		5,614			2.69
Options exercised		(131	)		1.43
Options cancelled:
Options forfeited (unvested)		(2,555	)		3.31
Options cancelled (vested)		(969	)		3.34
Balance at December 31, 2013		15,765			3.17		5.26	$	1,427
Vested and expected to vest at December 31, 2013		15,765			3.17		5.26	$	1,427
Exercisable at December 31, 2013		10,628			3.36		3.61	$	1,289

Summary of Restricted Stock Units Activity

	Number of Shares (In thousands)			Weighted-Average Grant-Date Fair Value
Non-vested as of December 31, 2012		1,755		$	4.23
Granted		250		$	1.23
Vested		(115	)	$	1.10
Forfeited or expired		(615	)	$	4.23
Non-vested as of December 31, 2013		1,275		$	3.93

Fair Value-Based Measurements and Weighted-Average Assumptions

	Stock Options									Employee Stock Purchase Plan
	Year Ended December 31,									Year Ended December 31,
	2013			2012			2011			2013			2012			2011
Weighted-average fair value	$	2.41		$	3.30		$	2.76		$	0.93		$	3.54		$	2.09
Risk-free interest rate		1.1	%		0.5	%		1.3	%		0.2	%		0.2	%		0.3	%
Expected life (in years)		5.9			4.2			4.0			1.3			1.1			1.2
Volatility		1.4			1.6			1.6			0.8			1.6			1.6

Stock-Based Compensation Expense

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

	Year Ended December 31,
	2013		2012		2011
Employees and directors stock-based compensation expense	$	11,828	$	10,439	$	5,185
Non-employees stock-based compensation expense		512		-		4
Total	$	12,340	$	10,439	$	5,189

	Year Ended December 31,
	2013		2012		2011
Research and development	$	4,228	$	3,514	$	2,103
General and administrative		8,112		6,925		3,086
Total	$	12,340	$	10,439	$	5,189

Income Taxes (Tables)

12 Months Ended

Dec. 31, 2013

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

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

	Year Ended December 31,
	2013			2012			2011
U.S.	$	(67,004	)	$	(70,792	)	$	(49,990	)
Non U.S.		284			843			1,393
Total	$	(66,720	)	$	(69,949	)	$	(48,597	)

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

	Year Ended December 31,
	2013			2012			2011
Income tax benefit at federal statutory rate	$	(22,678	)	$	(23,650	)	$	(16,523	)
State tax		(178	)		(89	)		(2,586	)
Business credits		(2,515	)		-			(1,394	)
Deferred compensation charges		3,072			1,002			595
Change in valuation allowance		22,354			21,966			18,099
Change in foreign tax rates		-			-			(34	)
Change in the fair value measurements		-			-			286
Non-deductible debt discount		-			-			509
Deemed dividend		-			-			273
Prior year true up		-			-			-
Other		(55	)		771			775
Total income tax expense	$	-		$	-		$	-

Component of Deferred Tax Assets and Liabilities

Deferred tax assets and liabilities as of December 31, 2013 and 2012 consisted of the following (in thousands):

	December 31,
	2013			2012
Deferred tax assets:
Net operating loss carry forwards	$	147,655		$	127,529
Research tax credit carry forwards		21,336			18,163
Accruals and reserves		9,501			8,529
Capitalized research costs		10,662			12,757
Deferred revenue		2,486			2,180
Other		1,222			1,221
		192,862			170,379
Less valuation allowance		(192,733	)		(170,232	)
Total deferred tax assets		129			147
Deferred tax liabilities:
Fixed Assets		(162	)		(86	)
Other		33			(61	)
Total deferred tax liabilities		(129	)		(147	)
Net deferred tax assets	$	-		$	-

Selected Quarterly Financial Data (Tables)

12 Months Ended

Dec. 31, 2013

Selected Quarterly Financial Data

	Year Ended December 31, 2013
	Q1			Q2			Q3			Q4
Revenues	$	2,085		$	3,392		$	2,927		$	2,847
Net loss	$	(20,825	)	$	(17,164	)	$	(15,675	)	$	(13,056	)
Net loss allocable to common stockholders	$	(20,825	)	$	(17,164	)	$	(15,675	)	$	(21,525	)
Basic and diluted net loss per share allocable to common stockholders	$	(0.11	)	$	(0.09	)	$	(0.09	)	$	(0.09	)
Shares used to compute basic and diluted net loss per share allocable to common stockholders		182,847			182,913			183,022			235,879

	Year Ended December 31, 2012
	Q1			Q2			Q3			Q4
Revenues	$	2,350		$	2,684		$	2,874		$	1,806
Net loss	$	(16,505	)	$	(15,110	)	$	(17,791	)	$	(20,543	)
Net loss allocable to common stockholders	$	(16,505	)	$	(15,110	)	$	(17,791	)	$	(20,543	)
Basic and diluted net loss per share allocable to common stockholders	$	(0.11	)	$	(0.09	)	$	(0.10	)	$	(0.11	)
Shares used to compute basic and diluted net loss per share allocable to common stockholders		155,431			167,697			177,870			180,685

Summary of Significant Accounting Policies - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2013 USD ($) Segment	Dec. 31, 2012 USD ($)	Dec. 31, 2011 USD ($)
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Cash, cash equivalents and marketable securities	$ 189,400,000
Number of reporting units \| Segment	1
Unrecognized tax benefits	$ 0
Unrecognized tax benefits, accrued amounts for interest and penalties	0
Amount reclassified out of accumulated other comprehensive (loss) income	$ 0
Number of Operating Segment \| Segment	1
United States
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Percentage of revenue earned	89.00%	88.00%	94.00%
Percentage of long lived assets	9.00%	10.00%
Maximum
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Cash equivalents original maturity period	3 months
Rhein
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Currency translation adjustments	$ 500,000	$ 400,000	$ (300,000)
Currency transaction gain (loss)	$ (200,000)	$ (200,000)	$ 200,000

Component of Property and Equipment (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012
Property Plant And Equipment [Line Items]
Manufacturing equipment	$ 8,968	$ 7,574
Property, Plant and Equipment, Gross	26,023	23,611
Furniture and fixtures	1,056	983
Leasehold improvements	6,048	5,445
Assets in progress	762	1,047
Less accumulated depreciation and amortization	(17,317)	(15,646)
Total	$ 8,706	7,965
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
Property Plant And Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 7,227	6,755
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
Property, Plant and Equipment, Gross	$ 1,962	$ 1,807
Furniture and Fixtures
Property Plant And Equipment [Line Items]
Estimated Useful Lives (In years)	3 years
Leasehold Improvements \| Minimum
Property Plant And Equipment [Line Items]
Estimated Useful Lives (In years)	5 years
Leasehold Improvements \| Maximum
Property Plant And Equipment [Line Items]
Estimated Useful Lives (In years)	7 years

Symphony Dynamo, Inc. - Additional Information (Detail) $ in Thousands	1 Months Ended									3 Months Ended	12 Months Ended
	Oct. 31, 2013 shares	May 09, 2012 shares	Nov. 03, 2011 shares	Nov. 02, 2010 shares	Jun. 30, 2010 USD ($)	Apr. 30, 2010 $ / Right shares	Apr. 16, 2010 $ / Right shares	Nov. 30, 2009 USD ($) $ / Right shares	Apr. 18, 2006 USD ($) $ / Right shares	Jun. 30, 2010 USD ($)	Dec. 31, 2013 $ / Right shares	Dec. 31, 2012 USD ($)	Dec. 31, 2011 USD ($)	Dec. 31, 2010 USD ($)	Apr. 30, 2007 USD ($)
Business Acquisition Equity Interests Issued Or Issuable [Line Items]
Warrants issued to purchase common stock \| shares						7,038,210		2,000,000
Warrants exercisable period						5 years	5 years	5 years	5 years
Warrants exercise price \| $ / Right						1.50	1.50	1.94	7.32		1.96
Warrant exercised															$ 15,000
Common stock issue on acquisition \| shares								13,000,000
Issued note to Holdings, principal amount								$ 15,000
Principal amount, due date								Dec. 31, 2012
Business acquisition contingent consideration percentage								50.00%
Business acquisition upfront payment								$ 50,000
Net present value model, discount rate											17.00%
Repayment of note payable												$ 15,000
Issuance of common stock, net of issuance costs (in shares) \| shares	79,570,000	17,500,000	27,600,000	26,450,000		1,076,420	30,293,000
Non operating income expense										$ 11,100
Warrants outstanding \| shares											10,913,873
Cash flows discounted rate														16.00%
Fair Value, Inputs, Level 3
Business Acquisition Equity Interests Issued Or Issuable [Line Items]
Changes in warrant and contingent consideration liability													$ 800	$ 2,200
Estimated fair value of contingent liability													$ 0
Warrant Liability
Business Acquisition Equity Interests Issued Or Issuable [Line Items]
Changes in warrant and contingent consideration liability					$ 9,500
Increase in additional paid in capital					1,600
Reclassification of warranty liability into equity					$ 12,000
Maximum
Business Acquisition Equity Interests Issued Or Issuable [Line Items]
Warrants issued to purchase common stock \| shares									2,000,000
SDI
Business Acquisition Equity Interests Issued Or Issuable [Line Items]
Investments in SDI									$ 50,000
Ownership percentage by parent									100.00%
Warrants outstanding \| shares											6,765,128
Holdings
Business Acquisition Equity Interests Issued Or Issuable [Line Items]
Ownership percentage by parent									100.00%

Commitments and Contingencies - Additional Information (Detail) $ in Thousands, € in Millions	3 Months Ended	12 Months Ended
	Dec. 31, 2004 USD ($)	Dec. 31, 2013 USD ($)	Dec. 31, 2012 USD ($)	Dec. 31, 2011 USD ($)	Dec. 31, 2013 EUR (€)
Loss Contingencies [Line Items]
Unoccupied facility expense		$ 926
Rent expense, net		1,900	$ 1,700	$ 1,700
Deferred rent		600	600
Cash, cash equivalents and marketable securities		189,400
Future payments obligation		4,500
Deutsche Bank Securities
Loss Contingencies [Line Items]
Letter of credit pledged as security \| €					€ 0.2
Collateralized certificate of deposit		$ 200	200
Berkeley, California (the "Berkeley Lease")
Loss Contingencies [Line Items]
Operating leases expiration date		2018-06
Unoccupied facility expense		$ 900
Dusseldorf, Germany (the "Dusseldorf Lease")
Loss Contingencies [Line Items]
Operating leases expiration date		2023-03
Berkeley, California (the "Berkeley Lease")
Loss Contingencies [Line Items]
Letter of credit pledged as security	$ 400
Collateralized certificate of deposit		$ 400	$ 400
Terms of the lease	If the total amount of our cash, cash equivalents and marketable securities falls below $20 million for a period of more than 30 consecutive days during the lease term, the amount of the required security deposit will increase to $1.1 million, until such time as our projected cash and cash equivalents will exceed $20 million for the remainder of the lease term, or until our actual cash and cash equivalents remains above $20 million for a period of 12 consecutive months.
Berkeley, California (the "Berkeley Lease") \| Contingency, B
Loss Contingencies [Line Items]
Contingency period for cash, cash equivalents and marketable securities	12 months
Berkeley, California (the "Berkeley Lease") \| Contingency, B \| Minimum
Loss Contingencies [Line Items]
Cash, cash equivalents and marketable securities	$ 20,000
Berkeley, California (the "Berkeley Lease") \| Contingency, A
Loss Contingencies [Line Items]
Increase in amount of the security deposit	$ 1,100
Berkeley, California (the "Berkeley Lease") \| Contingency, A \| Minimum
Loss Contingencies [Line Items]
Contingency period for cash, cash equivalents and marketable securities	30 days
Berkeley, California (the "Berkeley Lease") \| Contingency, A \| Maximum
Loss Contingencies [Line Items]
Cash, cash equivalents and marketable securities	$ 20,000

Collaborative Research, Development, and License Agreements - Additional Information (Detail) $ in Thousands	1 Months Ended				3 Months Ended			12 Months Ended
	Oct. 31, 2011 USD ($)	Dec. 31, 2008 USD ($) Project	Sep. 30, 2008 USD ($)	Sep. 30, 2006	Dec. 31, 2013 USD ($)	Dec. 31, 2012 USD ($)	Mar. 31, 2012 USD ($)	Dec. 31, 2013 USD ($)	Dec. 31, 2012 USD ($)	Dec. 31, 2011 USD ($)	Sep. 30, 2013 USD ($)	Jun. 30, 2012 USD ($)	May 31, 2012 USD ($)	Jul. 31, 2011 USD ($)	Aug. 31, 2010 USD ($)	Jul. 31, 2010 USD ($)
Product Information [Line Items]
Revenue from milestone payment										$ 12,000
Glaxo, Smith, Kline
Product Information [Line Items]
Number of programs for research and early clinical development \| Project		4
Collaboration Revenue		$ 10,000						$ 1,702	$ 1,428	1,428
Revenue from milestone payment										15,000
Additional revenue recognized					$ 300
Deferred revenue					2,500	$ 4,200		2,500	4,200
Glaxo, Smith, Kline \| Expansion
Product Information [Line Items]
Revenue from milestone payment										3,000
Glaxo, Smith, Kline \| Maximum
Product Information [Line Items]
Potential milestone payment					$ 125,000			$ 125,000
Deferred revenue recognition period					7 years			7 years
Glaxo, Smith, Kline \| Maximum \| Annual net sales milestones achieved
Product Information [Line Items]
Potential milestone payment					$ 60,000			$ 60,000
Glaxo, Smith, Kline \| Minimum
Product Information [Line Items]
Deferred revenue recognition period					6 years			6 years
Astra Zeneca
Product Information [Line Items]
Collaboration Revenue								$ 720	720	120
Revenue from milestone payment								$ 2,507	2,462	642
Deferred revenue recognition period					50 months			50 months
Deferred revenue					$ 4,800	7,700		$ 4,800	$ 7,700
Research collaboration and license agreement period				3 years
Amendment
Product Information [Line Items]
Collaboration Revenue	$ 3,000
Cost of clinical development activities										$ 20,000
Amendment \| Advance the program following completion of Phase 2a
Product Information [Line Items]
Collaboration Revenue						$ 6,000	$ 2,600
Revenue from milestone payment								20,000
Amendment \| Maximum \| Advance the program following completion of Phase 2a
Product Information [Line Items]
Revenue from milestone payment								$ 100,000
Hepatic Fibrosis and Cirrhosis \| National Institutes of Health
Product Information [Line Items]
Grants receivable											$ 200
Autoimmune Disease \| National Institutes of Health
Product Information [Line Items]
Grants receivable												$ 600
Rheumatoid Arthritis \| National Institutes of Health
Product Information [Line Items]
Grants receivable													$ 400
Skin Autoimmune Inflammation \| National Institutes of Health
Product Information [Line Items]
Grants receivable														$ 600
HBV \| National Institutes of Health
Product Information [Line Items]
Grants receivable															$ 1,400
HPV \| National Institutes of Health
Product Information [Line Items]
Grants receivable																$ 600
ISS Technology \| National Institutes of Health
Product Information [Line Items]
Contract agreement period			5 years
Contract awarded to develop technology			$ 17,000

Computation of Basic and Diluted Earnings Per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Basic and diluted net loss per share (in thousands, except per share amounts):
Net loss	$ (13,056)	$ (15,675)	$ (17,164)	$ (20,825)	$ (20,543)	$ (17,791)	$ (15,110)	$ (16,505)	$ (66,720)	$ (69,949)	$ (48,597)
Preferred stock deemed dividend									(8,469)
Net loss allocable to common stockholders	$ (21,525)	$ (15,675)	$ (17,164)	$ (20,825)	$ (20,543)	$ (17,791)	$ (15,110)	$ (16,505)	$ (75,189)	$ (69,949)	$ (48,597)
Denominator for basic and diluted net loss per share allocable to common stockholders:
Weighted-average common shares outstanding	235,879	183,022	182,913	182,847	180,685	177,870	167,697	155,431	196,275	170,469	125,101
Net loss per share allocable to common stockholders - basic and diluted	$ (0.09)	$ (0.09)	$ (0.09)	$ (0.11)	$ (0.11)	$ (0.10)	$ (0.09)	$ (0.11)	$ (0.38)	$ (0.41)	$ (0.39)
Outstanding securities not included in diluted net loss per share calculation (in thousands):
Outstanding securities not included in diluted net loss per share calculation									72,934	28,275	36,830
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									43,430
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									17,040	15,561	11,101
Warrant
Outstanding securities not included in diluted net loss per share calculation (in thousands):
Outstanding securities not included in diluted net loss per share calculation									12,464	12,714	25,729

Preferred Stock, Common Stock and Warrants - Additional Information (Detail)	1 Months Ended												12 Months Ended
	Oct. 31, 2013 USD ($) $ / shares shares	Mar. 29, 2013 USD ($)	May 09, 2012 USD ($) $ / shares shares	Nov. 03, 2011 USD ($) $ / shares shares	Nov. 02, 2010 USD ($) $ / shares shares	Sep. 30, 2010 USD ($) shares	Sep. 20, 2010 USD ($)	Apr. 30, 2010 $ / Right shares	Apr. 16, 2010 USD ($) $ / shares $ / Right shares	Nov. 30, 2009 $ / Right	Nov. 04, 2008 $ / shares	Apr. 18, 2006 $ / Right	Dec. 31, 2013 USD ($) $ / shares $ / Right shares	Dec. 31, 2012 USD ($) $ / shares shares	Dec. 31, 2011 USD ($) shares	Dec. 31, 2010 USD ($) shares	May 29, 2013 shares
Preferred Stock Common Stock And Warrants [Line Items]
Common stock, shares authorized													350,000,000	250,000,000			350,000,000
Preferred stock, shares authorized													5,000,000	5,000,000
Preferred stock, shares outstanding													0	0
Stock issued during period, shares	79,570,000		17,500,000	27,600,000	26,450,000			1,076,420	30,293,000
Preferred stock, par value \| $ / shares											$ 0.001		$ 0.001	$ 0.001
Public offering net price per share \| $ / shares	$ 1.075		$ 4.25	$ 2.50	$ 1.70				$ 1.4525
Issuance costs \| $									$ 3,000,000
Net proceeds from offering \| $			$ 69,600,000	$ 64,500,000	$ 42,000,000				$ 41,100,000
Common stock, par value \| $ / shares											$ 0.001		$ 0.001	$ 0.001
Dividends payable date											Nov. 17, 2008
Preferred shares price \| $ / shares											$ 6.00
Rights expiration date											Nov. 17, 2008
Common stock aggregate offering price \| $													$ 80,999,000
Sale of stock pursuant to exercise of underwriters overallotment option				3,600,000	3,450,000
Proceeds from issuances of common stock \| $													$ 80,856,000	$ 71,780,000	$ 91,298,000
Number of shares of common stock in each unit									1
Number of warrants in each unit									1
Number of share per warrant									0.5
Warrants exercise price \| $ / Right								1.50	1.50	1.94		7.32	1.96
Warrants exercisable period								5 years	5 years	5 years		5 years
Warrants outstanding													10,913,873
Warrants to purchase common stock													12,500,000
Number Of Warrants Exercised During Period													250,000	13,000,000
SDI
Preferred Stock Common Stock And Warrants [Line Items]
Warrants outstanding													6,765,128
2007 Loan Agreement
Preferred Stock Common Stock And Warrants [Line Items]
Warrants outstanding													1,550,000
Issuance of warrants for common shares to be purchased													3,550,000
Common Stock
Preferred Stock Common Stock And Warrants [Line Items]
Stock issued during period, shares													79,570,000
Gross proceeds from issuance of stock \| $	$ 85,500,000
Issuance costs \| $	4,500,000
Net proceeds from offering \| $	$ 80,900,000
Common stock aggregate offering price \| $													$ 80,000
Minimum
Preferred Stock Common Stock And Warrants [Line Items]
Percentage of common shares outstanding											20.00%
Percentage of assets											50.00%
Series B Convertible Preferred Stock
Preferred Stock Common Stock And Warrants [Line Items]
Preferred stock, shares authorized													43,000	0
Preferred stock, shares outstanding													0	0
Stock issued during period, shares	43,430
Preferred stock, par value \| $ / shares	$ 0.001
Public offering net price per share \| $ / shares	$ 1,075
Gross proceeds from issuance of stock \| $	$ 46,700,000
Issuance costs \| $	2,500,000
Net proceeds from offering \| $	$ 44,200,000
Convertible common stock shares													1,000
Convertible preferred stock, terms of conversion													The holder is prohibited from converting the Series B Convertible Preferred Stock into shares of common stock if, as a result of such conversion, the holder and its affiliates would own more than 9.98% of the total number of shares of common stock then issued and outstanding.
Convertible preferred stock, settlement terms													In the event of the Company’s liquidation, dissolution, or winding up, holders of Series B Convertible Preferred Stock will receive a payment equal to $0.001 per share before any proceeds are distributed to the common stockholders.
Convertible common stock exceeded allocated purchase price of preferred stock \| $													$ 8,500,000
MLV \| Maximum
Preferred Stock Common Stock And Warrants [Line Items]
Common stock aggregate offering price \| $		$ 50,000,000
Commission on gross sales proceeds of common stock		3.00%
Aspire Capital Fund Llc
Preferred Stock Common Stock And Warrants [Line Items]
Stock issued during period, shares															10,995,210	2,350,000
Purchase agreement term							25 months
Percentage of commitment to purchase shares value as commitment fee							4.00%
Commitment fee paid \| $						$ 1,200,000
Issuance of shares of common stock for commitment fee						600,000
Proceeds from issuances of common stock \| $															$ 26,700,000	$ 3,300,000
Aspire Capital Fund Llc \| Maximum
Preferred Stock Common Stock And Warrants [Line Items]
Commitment to purchase shares value \| $							$ 30,000,000

Equity Plans and Stock-Based Compensation - Additional Information (Detail) $ / shares in Units, $ in Thousands	1 Months Ended				12 Months Ended
	May 29, 2013 shares	Jan. 31, 2011 shares	Jan. 31, 2010 shares	Jan. 31, 2004 shares	Dec. 31, 2013 USD ($) CompensationPlan Employee $ / shares shares	Dec. 31, 2012 USD ($) Employee $ / shares shares	Dec. 31, 2011 USD ($) $ / shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of share-based compensation plans \| CompensationPlan					3
Expiration period					10 years
Number of shares of Common Stock outstanding					15,765,000	13,806,000
Total intrinsic value of options exercised \| $					$ 300	$ 2,700	$ 100
Total fair value of stock options vested \| $					$ 12,100	9,600	2,800
Options vesting period					4 years
Options and restricted stock units outstanding					2,047,466
Expected dividend yield					0.00%
Recognized stock-based compensation expense \| $					$ 4,900	1,500
Stock compensation expense \| $					$ 12,340	$ 10,439	$ 5,189
Number of employees under stock option \| Employee					5	1
Total unrecognized compensation cost related to non-vested equity awards \| $					$ 3,800
Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares reserved and approved for issuance					996,000
Total unrecognized compensation cost related to non-vested equity awards \| $					$ 100
Total unrecognized compensation cost, weighted-average vesting period					1 year 4 months 24 days
Shares issued to employees					828,414
Shares remaining available for future purchases					167,586
Employee Stock Purchase Plan \| The commencement of the offer 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%
Employee Stock Purchase Plan \| The exercise date, which is the last day of a purchase period (generally, the fourteenth 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%
Non Employee Awards
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock compensation expense \| $					$ 500
Additional
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Recognized stock-based compensation expense \| $					1,300	$ 700
Restricted Stock Units (RSUs)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock based compensation expense related to restricted stock \| $					100
Aggregate intrinsic value \| $					$ 2,500
Grant date fair value of restricted stock \| $ / shares					$ 1.23	$ 4.23	$ 0
Total fair value of restricted stock units \| $					$ 100	$ 200	$ 800
2004 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Purchase price per share as percentage of fair market value of common stock				100.00%
Number of shares of Common Stock outstanding					4,066,277
Inducement Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares of Common Stock outstanding					743,625
2011 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expiration period		10 years
Number of shares of Common Stock outstanding					10,954,940
Shares reserved and approved for issuance					13,666,964
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 \| $					$ 10,300
Total unrecognized compensation cost, weighted-average vesting period					2 years 9 months 18 days
Maximum \| 2004 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Issuance of common stock shares				3,500,000
Maximum \| 2004 Plan \| Other Participants
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expiration period				10 years
Maximum \| Inducement Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Issuance of common stock shares			1,500,000
Maximum \| 2011 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Issuance of common stock shares		25,000,000
Increase in the aggregate number of shares of common stock authorized for issuance	10,000,000
Minimum \| 2004 Plan \| Stock possessing more than 10% of the voting power of all classes of the Company's stock or the stock of any parent or subsidiary of the Company
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expiration period				5 years
Purchase price per share as percentage of fair market value of common stock				110.00%

Option Activity under Stock Plans (Detail) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2013 USD ($) $ / shares shares
Number of Options Outstanding
Beginning balance \| shares	13,806
Options granted \| shares	5,614
Options exercised \| shares	(131)
Ending balance \| shares	15,765
Vested and expected to vest at end of period \| shares	15,765
Exercisable at end of period \| shares	10,628
Weighted-Average Price Per Share
Beginning balance \| $ / shares	$ 3.38
Options granted \| $ / shares	2.69
Options exercised \| $ / shares	1.43
Ending balance \| $ / shares	3.17
Vested and expected to vest at end of period \| $ / shares	3.17
Exercisable at end of period \| $ / shares	$ 3.36
Weighted Average Remaining Contractual Life (In years)
Balance at December 31, 2013	5 years 3 months 4 days
Outstanding options vested and expected to vest at end of period	5 years 3 months 4 days
Options exercisable at end of period	3 years 7 months 10 days
Aggregate Intrinsic Value
Balance at December 31, 2013 \| $	$ 1,427
Outstanding options (vested and expected to vest) at end of period \| $	1,427
Options exercisable at end of period \| $	$ 1,289
Unvested
Number of Options Outstanding
Options cancelled \| shares	(2,555)
Weighted-Average Price Per Share
Options cancelled \| $ / shares	$ 3.31
Vested
Number of Options Outstanding
Options cancelled \| shares	(969)
Weighted-Average Price Per Share
Options cancelled \| $ / shares	$ 3.34

Difference between Consolidated Income Tax Benefit and Amount Computed by Federal Statutory Income Tax Rate (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Income Tax Rate Reconciliation [Line Items]
Income tax benefit at federal statutory rate	$ (22,678)	$ (23,650)	$ (16,523)
State tax	(178)	(89)	(2,586)
Business credits	(2,515)		(1,394)
Deferred compensation charges	3,072	1,002	595
Change in valuation allowance	22,354	21,966	18,099
Change in foreign tax rates			(34)
Change in the fair value measurements			286
Non-deductible debt discount			509
Deemed dividend			273
Prior year true up
Other	(55)	771	775
Total income tax expense

Component of Deferred Tax Assets and Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2013	Dec. 31, 2012
Deferred tax assets:
Net operating loss carry forwards	$ 147,655	$ 127,529
Research tax credit carry forwards	21,336	18,163
Accruals and reserves	9,501	8,529
Capitalized research costs	10,662	12,757
Deferred revenue	2,486	2,180
Other	1,222	1,221
Deferred Tax Assets, Gross, Total	192,862	170,379
Less valuation allowance	(192,733)	(170,232)
Total deferred tax assets	129	147
Deferred tax liabilities:
Fixed Assets	(162)	(86)
Other	33	(61)
Total deferred tax liabilities	(129)	(147)
Net deferred tax assets

Subsequent Events	12 Months Ended
Subsequent Events	Dec. 31, 2013
Subsequent Events	17. Subsequent Events In March, 2014 we announced a $5.4 million milestone payment and amendment of our AstraZeneca agreement to transfer responsibility for all clinical development to AstraZeneca following conclusion of the ongoing Phase 1 clinical trial of AZD 1419.

Component of Current Accrued Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2013	Dec. 31, 2012
Accrued Liabilities Abstract
Payroll and related expenses	$ 3,639	$ 4,538
Legal expenses	338	396
Third party research and development expenses	2,403	3,207
Other accrued liabilities	1,786	1,922
Total	$ 8,166	$ 10,063

Future Minimum Payments Under Non-Cancelable Portion of Operating Leases (Detail) $ in Thousands	Dec. 31, 2013 USD ($)
Operating Leased Assets [Line Items]
2014	$ 2,233
2015	2,282
2016	2,333
2017	2,382
2018	1,351
Thereafter	2,499
Total	$ 13,080

Income Taxes - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Income Tax Disclosure [Line Items]
Income tax expense
Increase (decrease) in valuation allowance	22.5	$ 22.0	$ 18.1
Amount of valuation allowance for deferred tax assets allocated to contributed capital	0.3
Federal
Income Tax Disclosure [Line Items]
Net operating loss carryforwards	$ 384.1
Federal \| Minimum
Income Tax Disclosure [Line Items]
Net operating loss carryforwards, expiration year	2018
Federal \| Maximum
Income Tax Disclosure [Line Items]
Net operating loss carryforwards, expiration year	2037
Federal \| Research And Development
Income Tax Disclosure [Line Items]
Tax credit carryforward amount	$ 13.8
Federal \| Research And Development \| Minimum
Income Tax Disclosure [Line Items]
Tax credit carryforward amount, expiration year	2018
Federal \| Research And Development \| Maximum
Income Tax Disclosure [Line Items]
Tax credit carryforward amount, expiration year	2033
California State
Income Tax Disclosure [Line Items]
Net operating loss carryforwards	$ 219.7
California State \| Minimum
Income Tax Disclosure [Line Items]
Net operating loss carryforwards, expiration year	2013
California State \| Maximum
Income Tax Disclosure [Line Items]
Net operating loss carryforwards, expiration year	2033
California State \| Research And Development
Income Tax Disclosure [Line Items]
Tax credit carryforward amount	$ 11.5
Foreign
Income Tax Disclosure [Line Items]
Net operating loss carryforwards	$ 27.8

Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2013	Dec. 31, 2012
Preferred stock, par value	$ 0.001	$ 0.001
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	350,000,000	250,000,000
Common stock, shares issued	262,796,000	182,792,000
Common stock, shares outstanding	262,796,000	182,792,000
Series B Convertible Preferred Stock
Preferred stock, shares authorized	43,000	0
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	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, 2013	Dec. 31, 2012
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	$ 187,610	$ 123,588
Fair Value, Inputs, Level 1
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	20,013	3,140
Fair Value, Inputs, Level 2
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	167,597	120,448
Money market funds
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	20,013	3,140
Money market funds \| Fair Value, Inputs, Level 1
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	20,013	3,140
US Government Agencies Debt Securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	167,597	119,233
US Government Agencies Debt Securities \| Fair Value, Inputs, Level 2
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	$ 167,597	119,233
US Treasury Securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets		500
US Treasury Securities \| Fair Value, Inputs, Level 2
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets		500
Municipal Securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets		715
Municipal Securities \| Fair Value, Inputs, Level 2
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets		$ 715

Summary of Cash, Cash Equivalents and Marketable Securities Available-for-sale (Detail) - USD ($) $ in Thousands	Dec. 31, 2013	Dec. 31, 2012
Cash Cash Equivalents And Marketable Securities [Line Items]
Amortized Cost	$ 189,407	$ 125,085
Unrealized Gains	16	46
Unrealized Losses	(47)	(1)
Estimated Fair Value	189,376	125,130
Cash and Cash Equivalents
Cash Cash Equivalents And Marketable Securities [Line Items]
Amortized Cost	23,122	7,599
Estimated Fair Value	23,122	7,599
Cash and Cash Equivalents \| Cash
Cash Cash Equivalents And Marketable Securities [Line Items]
Amortized Cost	1,766	1,542
Estimated Fair Value	1,766	1,542
Cash and Cash Equivalents \| Money market funds
Cash Cash Equivalents And Marketable Securities [Line Items]
Amortized Cost	20,013	3,140
Estimated Fair Value	20,013	3,140
Cash and Cash Equivalents \| US Government Agencies Debt Securities
Cash Cash Equivalents And Marketable Securities [Line Items]
Amortized Cost	1,343	2,202
Estimated Fair Value	1,343	2,202
Cash and Cash Equivalents \| Municipal Securities
Cash Cash Equivalents And Marketable Securities [Line Items]
Amortized Cost		715
Estimated Fair Value		715
Available-for-sale Securities
Cash Cash Equivalents And Marketable Securities [Line Items]
Amortized Cost	166,285	117,486
Unrealized Gains	16	46
Unrealized Losses	(47)	(1)
Estimated Fair Value	166,254	117,531
Available-for-sale Securities \| US Government Agencies Debt Securities
Cash Cash Equivalents And Marketable Securities [Line Items]
Amortized Cost	166,285	116,986
Unrealized Gains	16	46
Unrealized Losses	(47)	(1)
Estimated Fair Value	$ 166,254	117,031
Available-for-sale Securities \| US Treasury Securities
Cash Cash Equivalents And Marketable Securities [Line Items]
Amortized Cost		500
Estimated Fair Value		$ 500

Summary of Amortized Cost and Estimated Fair Value of Marketable Securities Available-for-sale (Detail) $ in Thousands	Dec. 31, 2013 USD ($)
Amortized Cost
Mature in one year or less	$ 93,691
Mature after one year through two years	72,594
Total amortized cost	166,285
Estimated Fair Value
Mature in one year or less	93,701
Mature after one year through two years	72,553
Total estimated fair value	$ 166,254

Summary of Revenue Recognized under Agreement with GSK (Detail) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended								12 Months Ended
	Dec. 31, 2008	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Product Information [Line Items]
Milestone revenue												$ 12,000
Total revenues		$ 2,847	$ 2,927	$ 3,392	$ 2,085	$ 1,806	$ 2,874	$ 2,684	$ 2,350	$ 11,251	$ 9,714	21,614
Grant revenue										5,138	3,939	3,110
National Institutes of Health
Product Information [Line Items]
Grant revenue										1,035	368	380
Glaxo, Smith, Kline
Product Information [Line Items]
Initial payment	$ 10,000									1,702	1,428	1,428
Milestone revenue												15,000
Total revenues										1,702	1,428	16,428
Astra Zeneca
Product Information [Line Items]
Initial payment										720	720	120
Milestone revenue										2,507	2,462	642
Total revenues										3,227	3,182	762
National Institute Of Allergy And Infectious Diseases
Product Information [Line Items]
Grant revenue										$ 4,103	$ 3,571	$ 2,730

Warrants Issued to Purchase Common Stock (Detail)	12 Months Ended
Warrants Issued to Purchase Common Stock (Detail)	Dec. 31, 2013 $ / Right shares	Apr. 30, 2010 $ / Right	Apr. 16, 2010 $ / Right	Nov. 30, 2009 $ / Right	Apr. 18, 2006 $ / Right
Class Of Warrant Or Right [Line Items]
Warrants exercise price \| $ / Right	1.96	1.50	1.50	1.94	7.32
Outstanding	10,913,873
2007 Loan Agreement
Class Of Warrant Or Right [Line Items]
Shares Issuable	3,550,000
Outstanding	1,550,000
Warrant One \| 2007 Loan Agreement
Class Of Warrant Or Right [Line Items]
Warrant Issuance Date	Jul. 18, 2007
Shares Issuable	1,250,000
Expiration Date	Feb. 26, 2014
Warrants exercise price \| $ / Right	5.13
Outstanding	1,250,000
Warrant Two \| 2007 Loan Agreement
Class Of Warrant Or Right [Line Items]
Warrant Issuance Date	Oct. 18, 2007
Shares Issuable	1,300,000
Expiration Date	Feb. 26, 2014
Warrants exercise price \| $ / Right	1.68
Warrant Three \| 2007 Loan Agreement
Class Of Warrant Or Right [Line Items]
Warrant Issuance Date	Dec. 27, 2007
Shares Issuable	300,000
Expiration Date	Feb. 26, 2014
Warrants exercise price \| $ / Right	5.65
Outstanding	300,000
Warrant Four \| 2007 Loan Agreement
Class Of Warrant Or Right [Line Items]
Warrant Issuance Date	Dec. 27, 2007
Shares Issuable	700,000
Expiration Date	Feb. 26, 2014
Warrants exercise price \| $ / Right	1.68

Subsequent Event - Additional Information (Detail) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
	Mar. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Subsequent Event [Line Items]
Milestone revenue				$ 12,000
Astra Zeneca
Subsequent Event [Line Items]
Milestone revenue		$ 2,507	$ 2,462	$ 642
Astra Zeneca \| Subsequent Event
Subsequent Event [Line Items]
Milestone revenue	$ 5,400