FDA Withdraws Approval of Pepaxto in Multiple Myeloma

The FDA has withdrawn the approval of Oncopeptides’ Pepaxto (melphalan flufenamide), which was approved for use in combination with dexamethasone to treat certain patients with multiple myeloma. The final decision was issued by FDA’s Center for Biologics Evaluation and Research Director Peter Marks, M.D., Ph.D.

Regulators indicated that the confirmatory study did not confirm Pepaxto’s clinical benefit, and the available evidence indicates Pepaxto is not safe or effective under its conditions of use.

Related: FDA Requests Removal of Pepaxto Indication for Multiple Myeloma

Pepaxto had been granted accelerated approval in the United States on Feb. 26, 2021, but at the FDA’s request, Oncopeptides stopped marketing Pepaxto in the United States on Oct. 22, 2021.

Regulators in December 2022 requested that Oncopeptides voluntarily withdraw the indication for Pepaxto. The request is based on the outcome of the confirmatory phase 3 OCEAN study, which demonstrated an overall survival hazard ratio of 1.1 in the intent to treat population. A hazard ratio of more than 1 indicates a risk of harm.

This request came after the September 2022 meeting of the FDA’s Oncologic Drugs Advisory Committee (ODAC), which voted 14 to 2 against full approval. Regulators had indicated that the confirmatory trial (OCEAN) demonstrated a worse overall survival and failed to verify clinical benefit.

The committee reviewed data from the OCEAN trial, which compared Peptaxto/dexamethasone with pomalidomide and dexamethasone in patients with relapsed or refractory multiple myeloma. Additionally, there were higher rates of deaths in Pepaxto arm than in the pomalidomide/dexamethasone arm. There were also higher rates of grade 3 and 4 adverse events in the Pepaxto arm.

In July 2023, the FDA had issued a formal request to withdraw Peptaxto, and in August 2023, the company had indicated it was appealing the ruling.

Sofia Heigis

“Our OCEAN study demonstrated clinical benefit for multiple myeloma patients, in particular for non-transplanted elderly patients where the unmet medical need remains very high, and we remain confident that it would provide value for patients all over the world, including the U.S.,” Sofia Heigis, CEO of Oncopeptides, said at the time in a press release.