DYNAVAX ANNOUNCES HIGH ENROLLMENT IN PEDIATRIC TRIAL

Dynavax Technologies announced that enrollment in the company's clinical trial of its AIC (Amb a 1 immunostimulatory conjugate) ragweed allergy immunotherapy in ragweed allergic children has exceeded expectations relative to speed of enrollment and number of study subjects.

More than three-hundred subjects aged six to 15 years have been enrolled in the 19-center trial in less than two and one-half months, exceeding the original expectation of 280 subjects. The company attributes the rapid, expanded enrollment to strong investigator and subject interest in AIC due to its demonstrated tolerability and its potential to offer a more effective and convenient therapy for ragweed allergic children. This clinical trial is designed to be supportive of the company's pivotal AIC Phase III trial, anticipated to begin in the first half of 2006.

The primary endpoint of this clinical trial is reduction in hay fever symptoms after two seasons and a secondary endpoint is the prevention of the development of asthma symptoms over three years.