Vanda Pharmaceuticals Requests FDA Review of Hetlioz Generics Approval

Vanda Pharmaceuticals has requested FDA Commissioner Marty Makary to review the approval of two generics of Hetlioz (tasimelteon). The generics were previously upheld by the retired director of the Center for Drug Evaluation and Research. The move comes after generic tasimelteon became available.

Vanda Pharmaceuticals (NASDAQ: VNDA) has formally requested U.S. FDA Commissioner Marty Makary to review the approval of two generics of Hetlioz (tasimelteon), following a recent decision by the retired director of the Center for Drug Evaluation and Research (CDER). The move comes after generic tasimelteon became available from Teva Pharmaceutical (TEVA) and Apotex. Vanda's challenge stems from concerns over the legitimacy of the generic approvals, which were upheld despite a 2022 court ruling that found some of Vanda's patents for Hetlioz to be invalid. The U.S. Supreme Court declined to hear Vanda's appeal in 2024.

The retired acting CDER Director Jacqueline Corrigan-Curay, who was in charge before her July retirement, agreed with an earlier decision that the generic approvals were legitimate. Vanda, however, contends that this decision means generic drug manufacturers need only conduct small studies involving Indian male subjects to establish bioequivalence for use in the general US population.

This request from Vanda is part of a broader legal battle that dates back to 2023 when the company submitted a citizen petition challenging the generic approvals. In August 2025, a Federal Appeals Court overturned an FDA order denying approval of Hetlioz for the treatment of jet lag disorder, marking a significant victory for Vanda [2].

References:
[1] https://seekingalpha.com/news/4488178-vanda-asks-fda-makary-review-approval-hetlioz-generics
[2] https://lifesciencereport.com/news/biotechnology