Dynavax Technologies Corporation provided a regulatory update for the company's supplemental Biologics License Application (sBLA) to include a four-dose HEPLISAV-B® vaccine [Hepatitis B Vaccine (Recombinant), Adjuvanted] regimen for adults on Hemodialysis. The U.S. Food and Drug Administration (FDA) has issued a Complete Response Letter (CRL) in response to the sBLA, stating that the application did not provide sufficient data to support the full evaluation of effectiveness or safety of a four-dose regimen of HEPLISAV-B. The CRL has no impact on the approved indication for HEPLISAV-B in the U.S., the European Union, and Great Britain, which is for the prevention of infection caused by all known subtypes of hepatitis B virus in adults 18 years of age and older. The CRL also does not affect the approval decision received from the European Commission in October 2023 for the four-dose HEPLIS AV-B regimen for the adult hemodialysis population.

The sBLA was comprised of clinical immunogenicity and safety data from the Phase 1 HBV-24 study of a four-dose regimen. The CRL stated that the data from HBV-24 were insufficient due to the destruction of data source documents by a third-party clinical trial site operator for approximately half of the subjects enrolled in the trial. In addition, the total number of subjects in the single-arm HBV-24 study was deemed to be insufficient to evaluate safety of the four-dose regimen.

Important U.S. Product Information: HEPLISAV-B is indicated for the prevention of infection caused by all known subtypes of hepatitis B virus in adults aged 18 years and older. Important U.S. Safety Information (ISI): Do not administer HEPLISAV-B to individuals with a history of a severe allergic reaction (e.g., anaphylaxis) after a previous dose of any hepatitis B vaccine or to any component of HEPLISAV-B, including yeast; Appropriate medical treatment and supervision must be available to manage possible anaphylactic reactions following administration of HEPLISAV-B; Immunocompromised persons, including individuals receiving immunosuppressant therapy, may have a diminished immune response to HEPLISAV-B; Hepatitis B has a long incubation period. HEPLISAV-B may not prevent hepatitis B infection in individuals who have an unrecognized hepatitis B infection at the time of vaccine administration; The most common patient-reported adverse reactions reported within 7 days of vaccination were injection site pain (23% to 39%), fatigue (11% to 17%), and headache (8% to 17%).