Dynavax Technologies announced that the FDA approved its vaccine Heplisav-B for the prevention of infection caused by all known subtypes of hepatitis B virus in adults age 18 years and older. The company noted that the product "is the first new hepatitis B vaccine in the [US] in more than 25 years and the only two-dose hepatitis B vaccine for adults."
According to Dynavax, approval of Heplisav-B was based on data from three late-stage studies that included nearly 10 000 patients who received the vaccine. The trials compared Heplisav-B administered in two doses over one month to GlaxoSmithKline's Engerix-B administered in three doses over a six-month schedule. Results from one of the studies showed that Heplisav-B had a significantly higher rate of protection of 95 percent compared with 81 percent for Engerix-B.
In August, the FDA delayed [2] a final decision regarding the approval of Heplisav-B after requesting additional information regarding its post-marketing study for the vaccine. The decision came after an FDA advisory panel voted [3] the previous month in favour of approval of Heplisav-B for use in adults. The regulator had declined [4] to approve Heplisav-B in 2016, in part due to a numerical imbalance in the incidence of cardiovascular events between the arms of one clinical study, while the therapy was previously rejected [5] over safety issues.
According to Dynavax, it expects to commercially launch Heplisav-B in the US in the first quarter of 2018. Commenting on the approval, RBC Capital Markets analyst Matthew Eckler said "our read of the label looks like a best-case scenario, with no red flags around safety." Eckler added "given Hepislav's superior efficacy and convenience profile, we continue to see potential to grow the current hep B vaccine market…through increased compliance, premium pricing and the capture of adult diabetic population, resulting in $300 million projected peak revenue."
Heplisav-B combines hepatitis B surface antigen with Dynavax's Toll-like receptor agonist to enhance the immune response.