BERKELEY, CA, USA I February 18, 2014 I Dynavax Technologies Corporation (NASDAQ: DVAX) announced today that it has withdrawn the European Marketing Authorization Application (MAA) for HEPLISAV, its investigational hepatitis B vaccine. The Day 180 List of Outstanding Issues provided by the European Medicines Agency (EMA) indicated that the current HEPLISAV safety database is considered to be too small to rule out a risk of less common serious adverse events. Dynavax has chosen to withdraw the application because the required timeframe for response under the MAA procedure is not long enough to permit the collection of the necessary clinical data. Dynavax expects to begin shortly an additional HEPLISAV clinical trial, HBV-23, that is intended to provide a safety database sufficient to support licensure.

About HEPLISAV

HEPLISAV is an investigational adult hepatitis B vaccine that combines hepatitis B surface antigen with a proprietary Toll-like Receptor 9 agonist to enhance the immune response. Dynavax has worldwide commercial rights to HEPLISAV.

About Dynavax

Dynavax, a clinical-stage biopharmaceutical company, discovers and develops novel vaccines and therapeutics in the areas of infectious and inflammatory diseases and oncology. Dynavax’s lead product candidate is HEPLISAV, a Phase 3 investigational adult hepatitis B vaccine. For more information visit www.dynavax.com.

SOURCE: Dynavax