The US Food and Drug Administration has declined Enzyvant’s regenerative tissue therapy for a rare immunodeficiency disorder and raised concerns about its manufacturing. The company was hoping to win its first approval for the therapy, RVT-802, aimed at treating congenital athymia, a disorder affecting babies born without a small gland called thymus, which produces T-cells needed to regulate the immune system. The health regulator in a letter to Enzyvant raised questions about the manufacturing process for the treatment as well as other issues based on its inspection of the manufacturing site. The company said it had planned to manufacture its treatment through a third-party manufacturer. If approved, RVT-802 would have been the first to win an FDA nod under the agency’s Regenerative Medicine Advanced Therapy (RMAT) designation, granted to drug developers making regenerative therapies for conditions lacking treatment options.
RVT-802 is a tissue-based therapy, manufactured by sourcing thymus tissue from infants undergoing heart surgeries unrelated to congenital athymia, and administered only once.