August 5 , 2004

Dynavax Reports 2004 Second Quarter Results

FOR IMMEDIATE RELEASE

BERKELEY, Calif., Aug. 5 /PRNewswire-FirstCall/ -- Dynavax Technologies Corporation (Nasdaq: DVAX), a biopharmaceutical company focused on the discovery, development, and commercialization of innovative products to treat and prevent allergies, infectious diseases, and chronic inflammatory diseases, today reported financial results for the quarter and six months ended June 30, 2004.

Dynavax reported a net loss of $2.9 million for the quarter ended June 30, 2004, or $0.12 per basic and diluted share, compared to a net loss of $4.0 million, or $2.23 per basic and diluted share for the same period in 2003. As of June 30, 2004, cash and cash equivalents totaled $74.0 million.

Revenue for the second quarter ended June 30, 2004 was $5.5 million, compared to $96,000 for the same period in 2003. The increase in revenue is due primarily to the Company's collaborative agreement with UCB Pharma in ragweed and grass allergies, which was initiated in 2004, and biodefense grants awarded by the National Institute of Allergy and Infectious Diseases.

Total operating expenses were $8.6 million for the second quarter ended June 30, 2004, compared to $4.2 million for the same period in 2003. The increase in operating expenses is primarily due to increased clinical trial activities in the Company's ragweed allergy, hepatitis B vaccine, and asthma programs, as well as preclinical work associated with government grants for biodefense programs. This increase also reflects higher compensation and benefits associated primarily with the expanding of our management team and higher expenditures for consulting and professional services.

For the six months ended June 30, 2004, total revenues were $8.7 million compared to $96,000 in the comparable period of 2003. The increase in revenues is due primarily to the collaborative agreement with UCB in ragweed and grass allergies, initiated in the first quarter of 2004, and biodefense grants awarded by the National Institute of Allergy and Infectious Diseases.

Operating expenses for the six months ended June 30, 2004 totaled $15.8 million as compared to $9.0 million in the comparable period of 2003. The increase in operating expenses is primarily due to increased clinical trial activities in the Company's ragweed allergy, hepatitis B vaccine, and asthma programs, as well as preclinical work associated with government grants for biodefense programs. This increase also reflects higher compensation and benefits associated primarily with the expanding of our management team and higher expenditures for consulting and professional services.

"We made solid progress on all fronts," said Dino Dina, M.D., President and Chief Executive Officer of Dynavax Technologies. "We met several important milestones in our clinical development programs, including full enrollment of our Phase II/III AIC trial for ragweed allergy, initiation of a Phase II/III trial of our hepatitis B prophylactic vaccine candidate, and the successful completion of immunizations in a Phase I pediatric trial of AIC for ragweed allergy. In addition, we have been effective in containing expenditures and maintaining a strong balance sheet."

About Dynavax Technologies Dynavax Technologies is a privately held biopharmaceutical company developing innovative products to treat allergy, inflammation-mediated diseases, infectious diseases and cancer. The company’s lead products are based on ImmunoStimulatory Sequences (ISS), short DNA sequences that enhance the ability of the immune system to fight disease and prevent inflammation. The company’s two most advanced products are AIC, which has provided positive results in recently completed phase II clinical trials for the treatment of ragweed allergy, and a next-generation hepatitis B vaccine that may offer single-dose protection. Dynavax is also developing an oral TNF-alpha synthesis inhibitor initially for the treatment of rheumatoid arthritis. The company has collaborations with Aventis-Pasteur, Triangle Pharmaceuticals and Stallergenes.

Contact: Andrew Gengos Chief Financial Officer Dynavax Technologies Corporation (510) 848-5100

Note: This press release contains "forward looking statements" within the meaning of the federal securities laws. These forward-looking statements include without limitation, statements relating to the potential success of product development, subsequent regulatory approvals and potential product sales. These statements are subject to risks and uncertainties that could cause actual results and events to differ materially from those anticipated. Readers are cautioned not to place undue reliance on these forward-looking statements that speak only as of the date of this release. Dynavax undertakes no obligation to update publicly any forward-looking statements to reflect new information, events or circumstances after the date of this release except as required by law.