BERKELEY, Calif. - August 4, 2009 - Dynavax Technologies Corporation (Nasdaq: DVAX) today reported financial results for the second quarter and six months ended June 30, 2009.

Dynavax reported $53.0 million in cash, cash equivalents, marketable securities and investments held by Symphony Dynamo, Inc. (SDI), collectively referred to as total cash, at June 30, 2009. This compared to $60.5 million at March 31, 2009.

Total revenues for the second quarter 2009 were $15.9 million, compared to $10.0 million reported for the second quarter in 2008. Total revenues were $35.2 million for the six months ended June 30, 2009, compared to $16.3 million for the same period in 2008. The significant increase in revenues for the second quarter and six months ended June 30, 2009 was primarily attributable to the recognition of $12.9 million and $28.5 million, respectively, of non-cash deferred revenue that was accelerated following the announcement of the termination of the Merck & Co., Inc. collaboration for HEPLISAV(TM), Dynavax's investigational hepatitis B vaccine. The Company completed the recognition of the non-cash deferred revenue relating to the HEPLISAV collaboration in the second quarter 2009.

On a pro forma basis, including collaboration funding from SDI and excluding the non-cash deferred revenue from the Merck collaboration, revenues were $3.7 million and $8.3 million, respectively, for the second quarter and six months ended June 30, 2009, compared to $10.8 million and $18.0 million for the same period in 2008.

Total operating expenses were $13.0 million for the second quarter 2009, compared to $16.6 million for the second quarter 2008. Total operating expenses were $28.0 million for the six months ended June 30, 2009, compared to $36.5 million for the same period in 2008. The decrease in operating expenses for 2009 was primarily due to a reduction in clinical development costs associated with HEPLISAV and the discontinuation of development for the TOLAMBA(TM) ragweed allergy program in May 2008.

On a pro forma basis, excluding the non-cash charges for stock-based compensation and amortization of intangible assets, operating expenses were $12.1 million and $26.3 million, respectively, for the second quarter and six months ended June 30, 2009, compared to $15.6 million and $34.6 million for the same periods in 2008.

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The tables included as part of this press release provide a reconciliation of GAAP revenues and operating expenses to pro forma revenues and operating expenses.

The net income of $4.1 million, or $0.10 per share, reported for the second quarter 2009 improved from the net loss of $6.1 million, or $0.15 per share, for the same period in 2008. The net income of $9.2 million, or $0.23 per share, reported for the six months ended June 30, 2009 was also significantly improved compared to the net loss of $18.5 million, or $0.47 per share, for the same period in 2008. The improvement in net loss for 2009 is due to the recognition of non-cash deferred revenue and a decrease in total operating expenses.

Phase 3 HEPLISAV Hepatitis B Vaccine - As reported in a separate press release today, Dynavax has met with the U.S. Food and Drug Administration (FDA) to discuss its plans to resume clinical development for HEPLISAV.

Clinical-Stage Programs - Dynavax's clinical-stage programs include Phase 1b hepatitis C and hepatitis B therapies.

Hepatitis C Therapy - SD-101 is a second generation TLR-9 agonist being developed for hepatitis C and is entirely funded through the SDI agreement. Phase 1 studies have demonstrated SD-101's safety, tolerability, and antiviral activity and Dynavax is reviewing future development options with Symphony Capital.

Hepatitis B Therapy - DV-601 combines both surface and core HBV antigens and Dynavax is planning to initiate a Phase 1b clinical trial.

Preclinical Programs - Dynavax's preclinical programs include programs partnered with pharmaceutical partners AstraZeneca and GlaxoSmithKline and the Company's Universal Flu vaccine. The vaccine has demonstrated its biological mechanism in a flu model.

Dynavax plans to provide its updated financial outlook for 2009 after determining the timing, scope, and funding for HEPLISAV's future development.

Dynavax Technologies Corporation, a clinical-stage biopharmaceutical company, discovers and develops novel products to prevent and treat infectious diseases. The Company's lead product candidate is HEPLISAV, a Phase 3 vaccine targeted for individuals who are less responsive to current licensed hepatitis B vaccines. For more information visit www.dynavax.com.

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Information on Dynavax's website at www.dynavax.com is not incorporated by reference in the Company's current periodic reports with the SEC.

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1. These amounts also included investments held by SDI of $22.8 million and $25.1 million as of June 30, 2009 and December 31, 2008, respectively.

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Amy Figueroa

Investor Relations and Corporate Communications

Phone: (510) 665-7211

BERKELEY, CA - August 4, 2009 - Dynavax Technologies Corporation (Nasdaq: DVAX) today announced it has met with the U.S. Food and Drug Administration (FDA) to discuss its plans to resume development of HEPLISAV(TM), the Company's Phase 3 investigational hepatitis B vaccine.

Dynavax proposed the continued clinical development of HEPLISAV in populations that are less responsive to current licensed hepatitis B vaccines, including adults over 40 years of age, individuals with chronic kidney disease, and other groups such as individuals infected with HIV or diagnosed with chronic liver disease. The FDA expressed a general agreement that these populations are appropriate for further clinical development, pending the review of the study protocols and additional supportive data.

Dynavax plans to submit this information to the FDA in August 2009 with a goal of having the agency remove the clinical hold in September 2009. The Company is prepared to restart clinical trials in individuals with chronic kidney disease upon removal of the clinical hold.

HEPLISAV is a Phase 3 investigational hepatitis B vaccine targeted for adults who are less responsive to current licensed hepatitis B vaccines, including adults over 40 years of age, individuals with chronic kidney disease (including end-stage renal disease, or ESRD, patients), and individuals infected with HIV or diagnosed with chronic liver disease (including hepatitis C virus).

Phase 3 data from the PHAST clinical trial demonstrate subjects over 40 years of age receiving two doses of HEPLISAV over one month achieved a seroprotection rate of 92%, compared to 75% of subjects receiving 3 doses of a licensed vaccine over six months. Over 2,500 individuals have been vaccinated with HEPLISAV to date.

Dynavax has worldwide commercial rights to HEPLISAV, which combines hepatitis B surface antigen (HBsAg) with a proprietary Toll-like Receptor 9 agonist to enhance the immune response.

Hepatitis B is a chronic disease which can lead to cirrhosis of the liver and hepatocellular carcinoma. There is no cure for hepatitis B and disease prevention through effective vaccination is critical to reducing the spread of the disease. The total worldwide market for adult hepatitis B vaccines is estimated at over $500 million annually.

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ESRD Market - The ESRD market is large and growing rapidly. In the United States alone, there are approximately 500,000 ESRD patients and 100,000 new patients annually, with similar numbers in Europe. CDC recommends universal vaccination of ESRD patients. Since ESRD patients are less responsive to current vaccines, hepatitis B vaccination regimens for ESRD consist of 8 doses of Engerix-B(R) over six months (versus 3 doses for the general population). Many ESRD patients do not respond to vaccination and boosters or revaccination is recommended. As ESRD patients are vaccinated regularly at dialysis centers, this is a highly concentrated, renewable market that can be served by cost-effective, targeted sales distribution networks.

Other Markets - In addition to ESRD patients, other populations such as individuals infected with HIV or diagnosed with chronic liver disease are also less responsive to current hepatitis B vaccines and represent a large, poorly served market opportunity.

Dynavax Technologies Corporation, a clinical-stage biopharmaceutical company, discovers and develops novel products to prevent and treat infectious diseases. The Company's lead product candidate is HEPLISAV, a Phase 3 vaccine targeted for individuals who are less responsive to current licensed hepatitis B vaccines. For more information visit www.dynavax.com.

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Engerix-B(R) is a licensed trademark of GlaxoSmithKline.