On March 22, the U.S. Food and Drug Administration (FDA) granted accelerated approval to the PD-1 inhibitor retifanlimab-dlwr (Zynyz) for adult patients with metastatic or recurrent locally advanced Merkel cell carcinoma.
Safety and efficacy were evaluated in PODIUM-201 (ClinicalTrials.gov identifier: NCT03599713), an open-label, multiregional, single-arm study evaluating 65 patients with metastatic or recurrent locally advanced Merkel cell carcinoma who had not received prior systemic therapy for advanced disease.
The major efficacy outcome measures were objective response rate and duration of response assessed by an independent central review committee according to Response Evaluation Criteria in Solid Tumors version 1.1. The objective response rate was 52% (95% confidence interval [CI] = 40%–65%), with a complete response rate of 18%. Twenty-six patients (76%) had a duration of response lasting at least 6 months, and 21 (62%) had a duration of response of 12 months or more.
The safety population consisted of 105 patients with Merkel cell carcinoma. The most common (≥ 10%) adverse reactions in patients receiving the agent were fatigue, musculoskeletal pain, pruritus, diarrhea, rash, pyrexia, and nausea. Serious adverse reactions occurred in 22% of patients receiving retifanlimab-dlwr.
The recommended retifanlimab-dlwr dose is 500 mg administered as an intravenous infusion over 30 minutes every 4 weeks until disease progression, unacceptable toxicity, or up to 24 months.
This review used the Assessment Aid, a voluntary submission from the applicant to facilitate the FDA’s assessment. This application was granted Priority Review as well as Fast Track status and Orphan Drug designation.The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.