Merck & Co., Inc. (NYSE: MRK) shares took a small step back on Thursday after the company announced a key approval from the U.S. Food and Drug Administration. The agency has now approved Keytruda the company’s anti-PD-1 therapy, for the treatment of adult and pediatric patients with refractory primary mediastinal large B-cell lymphoma (PMBCL).
This indication is approved under the FDA’s accelerated approval regulations based on tumor response rate and durability of response.
This approval was based on Merck’s KEYNOTE-170 trial, in which the overall response rate (ORR) was 45%, with a complete response rate (CRR) of 11% and a partial response rate of 34%. Median duration of response (DOR) was not reached. For the 24 responders, the median time to first objective response (complete or partial response) was 2.8 months. Median follow-up time was 9.7 months.
Looking ahead, continued approval for this indication may be contingent upon verification and description of clinical benefit in confirmatory trials. With this indication, Keytruda becomes the first anti-PD-1 therapy to be approved for the treatment of PMBCL, a type of non-Hodgkin lymphoma. This is the second indication for Keytruda for the treatment of a hematologic malignancy.
Philippe Armand, M.D., Ph.D., medical oncologist in the Hematologic Oncology Treatment Center at Dana-Farber Cancer Institute, commented:
Relapsed or refractory PMBCL is often a challenging disease to treat, and many affected patients are young adults. In the clinical trial that supported this approval, treatment with KEYTRUDA resulted in meaningful responses, including complete disease remission in some patients. This approval therefore provides another therapeutic option for patients with PMBCL who have progressed on or after prior therapies.
Shares of Merck were last seen down about 0.5% at $61.82, with a consensus analyst price target of $69.02 and a 52-week range of $52.83 to $66.41.