Why design of a postmarketing CV study has delayed Dynavax’s Heplisav-B, again
Following a long and bumpy regulatory road, it appears Heplisav-B from Dynavax Technologies Corp. is finally in the home stretch. But how the company and FDA handle the final hurdle -- the design of a postmarketing CV safety study -- may determine whether bigger challenges lie ahead.
What makes the problem interesting is that the patients in whom Heplisav-B is most effective are also those most at risk of myocardial infarction.
That could make it difficult for Dynavax to enroll enough high-risk patients in the observational study it has proposed to assess the actual risk represented by an imbalance in MIs, which occurred at low rates in a Phase III trial.
Panel members at a July 28 meeting of the Vaccines and Related Biological Products Advisory Committee (VRBPAC) voted 12 to one, with three abstentions, that the available data support Heplisav-B’s safety. They were not asked to make a recommendation on approval.
One member suggested that the FDA label include a warning or alert for patients with increased CV risk factors.
And although they thought the MI finding was likely