FDA Grants Priority Review to Melflufen in Combination with Dexamethasone for Myeloma

The FDA has granted a priority review to the new drug application (NDA) seeking approval for melflufen (INN melphalan flufenamide) in combination with dexamethasone (Ozurdex) for the treatment of adult patients with multiple myeloma whose disease is refractory to at least 1 proteasome inhibitor, 1 immunomodulatory agent, and 1 anti-CD-38 monoclonal antibody, according to Oncopeptides AB, the developer of the agent.1

A prescription drug user fee act (PDUFA) date has been set by the FDA for February 28, 2021.

“This is very exciting news. It is an important milestone for Oncopeptides, and a major step in making melflufen available for patients with multiple myeloma, who desperately need new treatment options,” Marty J. Duvall, CEO of Oncopeptides AB, said in a press release. “I am looking forward to a continuing dialogue with the FDA while we make the product available to RRMM patients in the US through an expanded access program, in an FDA approved trial called sEAPort.”

The NDA was based on results from the pivotal phase 2 HORIZON study, evaluating intravenous (IV) melflufen in combination with dexamethasone in patients with relapsed or refractory multiple myeloma. The study was fully recruited in October 2019 and the final data cut was made on January 14, 2020.2

Overall, 157 patients with multiple myeloma have been enrolled and evaluated. Notably, the HORIZON study population also includes subgroups of patients who were triple-class refractory and/or had extramedullary disease (EMD) and/or had cytogenetic high-risk features.

The primary end point was overall response rate (ORR).

In the intention to treat (ITT) population (n = 157), the investigator assessed ORR was 29% and the independent review committee (IRC) determined ORR was 30%. Among patients who were triple-class refractory (n = 119), the investigator assessed ORR was 26% and the IRC assessed ORR was also 26%. Moreover, in patients with EMD (n = 55), the ORR was 24% per investigator review and 27% per the IRC.

Importantly, the safety profile was consistent with previous reports from the HORIZON study with primarily hematologic adverse events (AE) observed and a low incidence of non-hematologic AEs seen.

References:

1. FDA grants Priority Review of melflufen for patients with triple-class refractory multiple myeloma [news release]. Stockholm. Published August 29, 2020. Accessed August 31, 2020. https://oncopeptides.se/en/fda-grants-priority-review-of-melflufen-for-patients-with-triple-class-refractory-multiple-myeloma/

2. Oncopeptides announces 26% Overall Response Rate of melflufen in triple-class refractory multiple myeloma patients from the pivotal HORIZON study [news release]. Stockholm. Published March 26, 2020. Accessed August 31, 2020. https://oncopeptides.se/en/oncopeptides-announces-26-overall-response-rate-of-melflufen-in-triple-class-refractory-multiple-myeloma-patients-from-the-pivotal-horizon-study/