The U.S. Food and Drug Administration (FDA) today granted accelerated approval to the anti–PD-1 antibody pembrolizumab (Keytruda) for the treatment of patients with advanced or unresectable melanoma who are no longer responding to other drugs.
Pembrolizumab is intended for use following treatment with ipilimumab (Yervoy). For melanoma patients with BRAF V600–positive tumors, pembrolizumab is intended for use after treatment with ipilimumab and a BRAF inhibitor.
“[Pembrolizumab] is the sixth new melanoma treatment approved since 2011, a result of promising advances in melanoma research,” said Richard Pazdur, MD, Director of the Office of Hematology and Oncology Products in the FDA’s Center for Drug Evaluation and Research. “Many of these treatments have different mechanisms of action and bring new options to patients with melanoma.”
The FDA action was taken under the agency’s accelerated approval program, which allows approval of a drug to treat a serious or life-threatening disease based on clinical data showing the drug has an effect on a surrogate endpoint reasonably likely to predict clinical benefit to patients.
Clinical Trial Results
Pembrolizumab’s efficacy was established in 173 clinical trial participants with advanced melanoma whose disease progressed after prior treatment. All study participants were treated with pembrolizumab, either at the recommended dose of 2 mg/kg or at a higher dose of 10 mg/kg.
In the half of the participants who received pembrolizumab at the recommended dose of 2 mg/kg, approximately 24% had their tumors shrink. A similar percentage of patients had their tumor shrink at the 10-mg/kg dose.
Pembrolizumab’s safety was established in the trial population of 411 participants with advanced melanoma. The most common side effects of the drug were fatigue, cough, nausea, pruritus, rash, decreased appetite, constipation, arthralgia, and diarrhea.
Severe immune-mediated side effects involving healthy organs, including the lung, colon, hormone-producing glands, and liver, were uncommon. ■