FDA Requests More Data on Dynavax's Hepatitis B Vaccine for Dialysis Patients

FDA Requests Further Data for HEPLISAV-B Vaccine

The Food and Drug Administration (FDA) has issued a Complete Response Letter (CRL) to Dynavax Technologies Corporation regarding their supplemental Biologics License Application (sBLA) for a four-dose regimen of the HEPLISAV-B vaccine. The vaccine is intended for adults who are undergoing hemodialysis.

The FDA's decision stems from insufficient data to fully assess the safety and efficacy of the proposed regimen. This decision does not impact the already approved use of HEPLISAV-B for preventing hepatitis B infection in adults.

Concerns Over Insufficient Data

The submitted sBLA was based on data from the Phase 1 HBV-24 study, which included 119 hemodialysis patients. Additional supportive trials were conducted in adults with chronic kidney disease or those undergoing hemodialysis. The CRL pointed out significant issues, such as the destruction of data source documents for nearly half of the enrolled subjects and an insufficient number of participants to adequately evaluate safety.

Despite these setbacks, Dynavax remains confident in the existing data and plans to seek further discussions with the FDA to address these concerns. The decision does not influence the FDA's prior acceptance of HEPLISAV-B for other uses.

European Approval Remains Unaffected

The European Commission had previously approved the four-dose HEPLISAV-B regimen for adult hemodialysis patients in October 2023. This approval remains unaffected by the FDA’s recent decision. The approval in Europe is based on the similar dataset.

Rob Janssen, MD, Chief Medical Officer of Dynavax, reaffirmed the company's confidence in the data supporting HEPLISAV-B for adult hemodialysis patients. According to Janssen, all critical data were verified thoroughly against original source documents during the conduct of the trial.

Future Steps for Dynavax

Dynavax is currently reviewing the feedback provided by the FDA and intends to request a meeting to explore the possibility of submitting additional data. This will help address the concerns raised regarding the four-dose regimen for this vulnerable patient population in the United States.

Moving forward, Dynavax aims to ensure that sufficient data is collected and verified to meet the FDA's stringent requirements. The company stresses the importance of this vaccine for adult hemodialysis patients who are at an increased risk of hepatitis B infection.

Key Developments and Next Steps

The CRL has prompted Dynavax to reassess their data collection strategies and work towards a comprehensive plan that aligns with the FDA's feedback. Understanding the seriousness of the issue, Dynavax highlights the urgency of addressing these concerns to facilitate approval.

The company's commitment to its patient population remains steadfast as they navigate the regulatory landscape to provide effective and safe vaccination options for those undergoing hemodialysis.

Conclusion

While the FDA's request for additional data delays the approval of the HEPLISAV-B four-dose regimen for adults undergoing hemodialysis, Dynavax remains proactive in addressing the regulatory hurdles. The commitment to patient safety and the eventual goal of approval drives their continuous efforts to meet the FDA's requirements.

With a focus on both the verification and validation of data, Dynavax will continue to work closely with regulatory bodies to ensure the best outcomes for patients requiring this vital vaccine.