Exhibit No.    Description

VP Operations & Chief Financial Officer

Phone: (510) 665-7222

BERKELEY, Calif. - August 5, 2008 - Dynavax Technologies Corporation (Nasdaq: DVAX) today reported financial results for the second quarter and six months ended June 30, 2008.

As of June 30, 2008, Dynavax reported cash, cash equivalents, marketable securities and investments held by Symphony Dynamo, Inc. (SDI) totaling $63.1 million. This compares to $88.2 million at December 31, 2007.

For the second quarter 2008, total revenues were $10.0 million, compared to $1.8 million reported for the second quarter in 2007. Revenues for the six months ended 2008 were $16.3 million, compared to $3.8 million for the same period in 2007. The increase in revenues for the second quarter and year-to-date reflects research and development funding under our collaboration with Merck & Co. Inc. (Merck) for HEPLISAV^TM, our hepatitis B vaccine product candidate. The reported revenues do not include collaboration funding from Symphony Dynamo Inc. (SDI) for cancer and HCV clinical activities. On a pro forma basis, including the collaboration funding from SDI, revenues were $11.4 million and $19.3 million for the three and six months ended June 30, 2008, respectively, compared to $4.9 million and $10.4 million for the same periods in 2007.

For the second quarter 2008, total operating expenses were $16.6 million, compared to $23.6 million for the second quarter in 2007. Operating expenses for the six months ended 2008 were $36.5 million, compared to $41.7 million for the same period in 2007. The decline in operating expenses for the second quarter and year-to-date resulted primarily from a reduction in clinical development costs. The operating expenses in 2007 also included a one-time license payment for the commercialization of HEPLISAV. Excluding the one-time and other non-cash charges for stock-based compensation and amortization of intangible assets, pro forma operating expenses were $15.6 million and $34.6 million for the three and six months ended June 30, 2008, respectively, compared to $17.7 million and $34.7 million for the same periods in 2007.

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.

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The net loss of $6.1 million, or $0.15 per share, reported for the second quarter 2008 improved from the net loss of $17.7 million, or $0.45 per share, for the same period in 2007. The net loss of $18.5 million, or $0.47 per share, reported for the six months ended 2008 was also significantly less than the net loss of $30.8 million, or $0.78 per share, for the same period in 2007. For the second quarter and year-to-date, the improvement in net loss reflected the increase in revenues, in particular, revenue associated with the Merck collaboration.

1. Total operating expenses excluding non-cash stock-based compensation charges are $15.8 million and $35.1 million for the three and six months ended June 30, 2008, respectively. Total operating expenses excluding non-cash stock-based compensation charges are $22.9 million and $40.2 million for the three and six months ended June 30, 2007, respectively.
2. Research and development expenses included non-cash stock-based compensation charges of $0.4 million and $0.6 million for the three and six months ended June 30, 2008, respectively. Research and development expenses included non-cash stock-based compensation charges of $0.3 million and $0.5 million for the three and six months ended June 30, 2007, respectively.
3. General and administrative expenses included non-cash stock-based compensation charges of $0.4 million and $0.9 million for the three and six months ended June 30, 2008, respectively. General and administrative expenses included non-cash stock-based compensation charges of $0.4 million and $1.0 million for the three and six months ended June 30, 2007, respectively.

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1. These amounts include investments held by SDI of $28.0 million and $31.6 million as of June 30, 2008 and December 31, 2007, respectively.

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BERKELEY, CA and WHITEHOUSE STATION, NJ - August 5, 2008 - Dynavax Technologies Corporation (Nasdaq: DVAX) and Merck & Co., Inc. announced today top-line immunogenicity results from a Phase 3 clinical trial comparing HEPLISAV™, an investigational hepatitis B virus (HBV) vaccine, to a currently marketed HBV vaccine, Engerix-B^{® *}. The study achieved its primary endpoint. HEPLISAV is being jointly developed by Dynavax and Merck for use in adults and in patients with end stage renal disease.

This study, called PHAST (Phase 3 HeplisAv Short-regimen Trial), evaluated a two-dose regimen of HEPLISAV administered at 0 and 1 month compared to a three-dose regimen of Engerix-B^® administered at 0, 1 and 6 months. The primary endpoint was the proportion of subjects who developed protective antibodies to hepatitis B after administration. In PHAST, 95.1 percent of subjects who received two doses of HEPLISAV (n=1,819) developed protective antibodies to hepatitis B when measured at 12 weeks versus 81.1 percent of subjects who received three doses of Engerix-B^® (n=608) when measured at 28 weeks. The multi-center study evaluated 2,427 subjects from 11 to 55 years of age in Canada and Germany. Results of additional analyses from this trial will be presented in the future.

As previously disclosed, the U.S. Food and Drug Administration (FDA) placed a clinical hold on the two Investigational New Drug (IND) Applications for HEPLISAV that is still in effect. In issuing the clinical hold, the FDA requested a review of clinical and preclinical safety data for HEPLISAV. Additionally, the FDA requested all available information about a single case of Wegener's granulomatosis reported in this Phase 3 trial.

HEPLISAV is based on Dynavax's proprietary immunostimulatory sequence (ISS) that specifically targets Toll-Like Receptor 9 (TLR9) to stimulate an innate immune response. HEPLISAV combines ISS with HBV surface antigen (HBsAg) and is designed to enhance the speed of protection.

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This press release contains "forward-looking statements." Actual results may differ materially from those set forth in this press release due to the risks and uncertainties inherent in our business, including difficulties or delays in development, initiation and completion of clinical trials, the results of clinical trials and the impact of those results on the initiation and completion of subsequent trials and issues arising in the regulatory process; achieving our Merck collaborative agreement objectives and obtaining regulatory approval for HEPLISAV; the scope and validity of patent protection and the possibility of claims against us based on the patent rights of others; our ability to obtain additional financing to support our operations; and other risks detailed in the "Risk Factors" section of our Quarterly Report on Form 10-Q. We undertake no obligation to revise or update information herein to reflect events or circumstances in the future, even if new information becomes available.

About Merck

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This press release contains "forward-looking statements" as that term is defined in the Private Securities Litigation Reform Act of 1995. These statements are based on management's current expectations and involve risks and uncertainties, which may cause results to differ materially from those set forth in the statements. The forward-looking statements may include statements regarding product development, product potential or financial performance. No forward-looking statement can be guaranteed and actual results may differ materially from those projected. Merck undertakes no obligation to publicly update any forward-looking statement, whether as a result of new information, future events, or otherwise. Forward-looking statements in this press release should be evaluated together with the many uncertainties that affect Merck's business, particularly those mentioned in the risk factors and cautionary statements in Item 1A of Merck's Form 10-K for the year ended Dec. 31, 2007, and in any risk facto rs or cautionary statements contained in the Company's periodic reports on Form 10-Q or current reports on Form 8-K, which the Company incorporates by reference.

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