Persistence pays off for Dynavax as twice-rejected hepatitis B vaccine wins FDA nod

Berkeley, California's Dynavax secured FDA approval for its hep B vaccine Engerix-B.

Dynavax completed the long road to approval for its hepatitis B vaccine Heplisav-B on Thursday, securing an FDA nod after two previous rejections. Now, the company is set to challenge GlaxoSmithKline's Engerix-B as it transitions into a commercial biotech. 

Heplisav-B's approval marks the first new hepatitis B vaccine in more than 25 years, following Engerix-B's greenlight way back in 1989. The FDA approved the Dynavax shot for prevention of infection from all known hepatitis B subtypes in people ages 18 and older.

Dynavax CEO Eddie Gray told FiercePharma his company has already hired a senior commercial team for the Heplisav-B launch, noting that the adult vaccine market is "quite a contained space" that's ideal for a small biotech's first marketing operation. He said the total commercial effort will comprise 45 to 50 people. Dynavax plans to launch the vaccine in the first quarter of 2018.

While Dynavax is willing to go it alone for the rollout, Gray said his company is also open to hearing out prospective partners. Analysts with RBC Capital Markets estimate Heplisav-B will generate $300 million in peak sales.

Before approval, Dynavax touted data showing its vaccine provides "higher and earlier protection with fewer doses than a currently licensed hepatitis B vaccine," according to an earlier release

Previously an executive at Glaxo, Gray said many Engerix-B recipients don't get the vaccine's required third dose. Dynavax's vaccine is given in two doses one month apart, a factor that should make it easier for recipients to complete the schedule. In combination with the efficacy data, that gives the vaccine a "very competitive profile in the market," he said.

But prospects for the hep B vaccine haven't always been certain. The FDA turned away the shot in 2013 and 2016, requesting more safety data and more details about postmarketing plans. 

RELATED: FDA extends review on Dynavax's Heplisav-B, but management remains confident 

This time around, the agency in August delayed its review by three months to further go over the company's postmarketing plans. At the time, executives said that plan includes a phase 4 study to monitor safety by tracking Heplisav-B recipients against those who receive the GSK shot. 

Going forward, Heplisav-B revenues will help fund continued R&D activities at the company, Gray said, including in immuno-oncology, where Dynavax has a collaboration with drug giant Merck. The biotech will also explore other applications for its newly approved adjuvant, 1018. 

GSK's Engerix-B was among a group of hepatitis shots that generated £602 million ($810 million) last year for Glaxo. VBI Vaccines is also working on a potential challenger.