Dynavax pops on FDA approval optimism for HBV vaccine

Small cap Dynavax ($DVAX) bounced up almost 20% on news that the FDA has requested information regarding its application for its hepatitis B vaccine. This isn’t the first time at the rodeo for the candidate, Heplisav-B, which was previously rejected by the agency in 2013.

The company also reaffirmed its upcoming FDA review date of Dec. 15; that date had already been pushed by the agency for three months. Prior to the recent uptick, Dynavax had been hovering near 52-week lows. Its shares dove in early September when the FDA disclosed that it had cancelled a Nov. 16 advisory committee meeting for Heplisav-B.

But now Wall Street is hoping that the latest FDA query paired with the cancelled panel meeting could actually prove to be good news for the biotech. In an SEC filing, the company said the agency’s recent requests for information were “anticipated” and “in line with the company’s expectations.”

In its 2013 explanation of the FDA’s complete response letter for Heplisav-B, Dynavax said the agency was concerned about an approval in the broad age group of 18 to 70 years old. It was also concerned that the adjuvants could cause rare autoimmune events.

In addition, the FDA wanted more data on the company’s process validation program and to clarify information on its manufacturing controls and facilities related to product quality.

In January, Dynavax reported on the data from a nearly 8,400-patient trial known as HBV-23 designed to address agency concerns. The study met its co-primary endpoints with a higher rate of seroprotection for Heplisav-B than for Engerix-B, an HBV vaccine from GlaxoSmithKline ($GSK), overall and specifically among diabetic participants.

Participants were randomized 2:1 to a Heplisav-B or an Engerix-B arm. There were 22 adverse events of special interest in the Heplisav-B arm, with 11 in the Engerix-B arm. Of these, 21 were determined to be autoimmune events with 11 of these in the Heplisav arm and 10 in the Engerix arm.

Dynavax has a market cap of about $480 million.