A second phase III trial in a younger adult population is scheduled to be conducted in Europe and Canada in early 2006. Assuming positive data from these trials, Dynavax could potentially file an application to market the hepatitis B (HBV) vaccine in 2007.
Dynavax’s HBV vaccine is based on its proprietary immunostimulatory sequence (ISS) that specifically targets toll-like receptor 9 (TLR-9) to stimulate an innate immune response. Dynavax’s HBV vaccine combines ISS with HBV surface antigen (HBsAg) and is designed to significantly enhance the level, speed and longevity of protection.
The multi-centre clinical trial will enroll more than 400 seronegative adults (with no detectable HBV antibodies). Participants will be divided into two groups, the first group will receive three doses of Dynavax’s HBV vaccine, administered at a dose of 20 micrograms HBsAg plus 3 milligrams of ISS, by intramuscular injection at zero, two months and six months.
The second group will receive three doses of Engerix-B administered at a dose of 20 micrograms HBsAg by intramuscular injection at zero, one and six months. The primary endpoint is seroprotection four weeks after the third vaccination, seven months into the study. Participants will then be followed for an additional five months. The trial is anticipated to be completed in the second half of 2006.
Dynavax plans to conduct additional trials in selected high-risk populations, such as dialysis patients, in targeted markets in Europe, Canada and potentially in the US.
Previous results show Dynavax’s vaccine to be significantly more effective than Engerix-B in both old and young adults, with greater protective antibody responses being achieved faster in those participants being treated with the Dynavax vaccine.
Dynavax is currently evaluating global commercialization and distribution strategies for its HBV vaccine. Dynavax has a long-term supply contract with Switzerland based Berna Biotech that includes a commercialization option. The companies are at the early stages of discussing this option.