The evaluation included data from 2717 subjects. Of the subjects enrolled in the Phase 3 lot-to-lot consistency study, all are at least two months past their final HEPLISAV injections. Furthermore, the first subjects enrolled in the Phase 3 chronic kidney disease study are now 12 months past their first dose.

Tyler Martin, M.D., President and Chief Medical Officer, commented, "The DSMB's recommendation that both Phase 3 trials continue without protocol modification is consistent with our expectation. Generally, one expects adverse events related to study drugs to occur in temporal proximity to the exposure. With 100% of subjects in the Phase 3 lot-to-lot consistency study now two months past the last HEPLISAV vaccination, our confidence in the safety of this product is reinforced. "

Dino Dina, M.D., Chief Executive Officer, added, "We have clearly advanced past a key milestone in both studies and are working to stay on our projected timeline for making regulatory submissions before the end of 2011. We have demonstrated HEPLISAV's efficacy in multiple prior trials and expect these trials to demonstrate efficacy in line with our previous results. The first of these Phase 3 trials was designed to confirm the consistency of our lots and to provide us a safety database that will be acceptable to the regulatory authorities in the U.S. and in Europe; the second was designed to demonstrate a regimen specifically for CKD patients. "

HEPLISAV is an innovative investigational vaccine designed to protect against hepatitis B infection. The DSMB reviewed safety data from two ongoing multi-center Phase 3 trials evaluating HEPLISAV, the first a lot-to-lot consistency trial in adults 40 years and older, and the second a trial in chronic kidney disease patients. The DSMB is comprised of an independent group of medical experts who are responsible for reviewing and evaluating subject safety data at regular intervals during the ongoing trials.

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HEPLISAV is an investigational adult hepatitis B vaccine. The vaccine candidate is being evaluated in two Phase 3 studies that are directed toward fulfilling licensure requirements in U.S., Canada and Europe. In a completed pivotal Phase 3 trial, HEPLISAV demonstrated increased, rapid protection with fewer doses than current licensed vaccines. Dynavax has worldwide commercial rights to HEPLISAV and is developing the vaccine for large, high-value populations that are less responsive to current licensed vaccines, including individuals with chronic kidney disease. HEPLISAV combines hepatitis B surface antigen with a proprietary Toll-like Receptor 9 agonist known as ISS to enhance the immune response.

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