FDA issues complete response letter for Heplisav-B [Hepatitis B Vaccine, Recombinant (Adjuvanted)] for immunization against hepatitis B infection.- Dynavax Technologies

Dynavax Technologies Corporation announced that it has received a Complete Response Letter (CRL) from the FDA regarding its Biologics License Application (BLA) for Heplisav-B [Hepatitis B Vaccine, Recombinant (Adjuvanted)] for immunization of adults 18 years and older against hepatitis B infection. The FDA issues CRLs to communicate that the Agency has completed a review cycle of an application and to request additional information for review and approval.

Dynavax expects a Class 2 designation for a resubmission of the BLA, which would result in a target review period of six months.The CRL seeks information regarding several topics, including clarification regarding specific adverse events of special interest (AESIs), a numerical imbalance in a small number of cardiac events in a single study (HBV-23), new analyses of the integrated safety data base across different time periods, and post-marketing commitments. In the CRL, the FDA acknowledged that it has not yet completed its review of responses received from Dynavax in early October, including those pertaining to AESIs and the numerical imbalance in cardiac events. The responses included an extensive analysis that included independent expert consultation supporting our view that the imbalance was driven by an unexpectedly low number of events in the comparator arm. It would appear the Agency could not fully assess the responses in the current review period. In the CRL, there is no request for additional clinical trials and there are no apparent concerns with rare serious autoimmune events.