Dynavax falls after Heplisav panel
Dynavax Technologies Corp. (NASDAQ:DVAX) lost nearly half its market cap on Friday after FDA's Vaccines and Related Biological Products Advisory Committee voted 8-5 with one abstention on Thursday that the company had not gathered enough safety data to support approval of Heplisav, an adjuvanted vaccine for HBV infection. Dynavax fell $2.19 (47%) to $2.44 on Friday, which translates to a loss in market cap of $391.4 million. The biotech's market cap is now $436 million.
Heplisav is a hepatitis B surface antigen (HBsAg) given with immunostimulatory DNA sequences that target toll-like receptor 9 (TLR9). Because there are no approved TLR9-based adjuvants, the majority of panel members requested additional safety data preapproval to fully characterize Heplisav's potential risks. A permanent voting member on the panel suggested that data for about 8,000 to 10,000 patients could be sufficient (see BioCentury Extra, Nov. 15). ...