FDA grants priority review to Libtayo for lung cancer subset
The FDA granted priority review to cemiplimab-rwlc for treatment of certain patients with non-small cell lung cancer.
The designation applies to use of the agent as first-line therapy for locally advanced or metastatic NSCLC with 50% or greater PD-L1 expression.
Cemiplimab-rwlc (Libtayo; Regeneron, Sanofi) — a fully human monoclonal antibody that targets PD-1 — is approved in the United States for treatment of adults with metastatic cutaneous squamous cell carcinoma or locally advanced cutaneous squamous cell carcinoma who are not candidates for curative surgery or curative radiation.
A supplemental biologics license application that seeks approval of the drug for the NSCLC indication is based on results of the randomized phase 3 EMPOWER-Lung1 trial.
The trial included 710 adults with stage IIIB or stage IIIC NSCLC — all of whom were not candidates for surgical resection or definitive chemoradiation or had progressed after chemoradiation — or previously untreated stage IV NSCLC. All patients had PD-L1 expression in at least 50% of tumor cells.
Researchers randomly assigned 356 patients to cemiplimab-rwlc dosed at 350 mg via IV every 3 weeks for up to 108 weeks. The other 354 patients received investigator’s choice of standard platinum-based doublet chemotherapy for four to six cycles, with or without maintenance pemetrexed.
Upon disease progression, patients assigned chemotherapy could cross over to cemiplimab-rwlc, and those assigned cemiplimab-rwlc had the opportunity to continue treatment with that agent in combination with four cycles of chemotherapy.
OS and PFS as assessed by blinded independent review committee served as primary endpoints. Secondary endpoints included overall response rate, duration of response and quality of life.
Median follow-up in the intention-to-treat population was 13.1 months.
As Healio previously reported, results presented during ESMO Virtual Congress 2020 showed cemiplimab-rwlc significantly prolonged PFS (6.2 months vs. 5.6 months; HR = 0.59; 95% CI, 0.49-0.72) and OS (22.1 months vs. 14.3 months; HR = 0.68; 95% CI, 0.53-0.87) in the intention-to-treat population.
Outcomes in the intention-to-treat population favored cemiplimab-rwlc with regard to response rate (36.5% vs. 20.6%; P < .0001) and median duration of response (21 months vs. 6 months).
The most common adverse events reported among patients assigned cemiplimab-rwlc included anemia (14.6% for cemiplimab-rwlc vs. 94.2% for chemotherapy), decreased appetite (11.8% vs. 18.4%), fatigue (10.1% vs. 17%), pneumonia (9.3% vs. 10.8%), constipation (7.6% vs. 15.2%) and nausea (6.2% vs. 28.4%).
The most common grade 3 or higher adverse events reported among patients assigned cemiplimab-rwlc included pneumonia (4.8% for cemiplimab-rwlc vs. 5.6% for chemotherapy) and anemia (3.4% vs. 16.4%).
A higher percentage of patients assigned cemiplimab-rwlc experienced treatment-related adverse events that led to treatment discontinuation (any grade, 5.1% vs. 3.5%; grade 3 or higher, 2.5% vs. 2.3%) or death (any grade, 2.5% vs. 2%; grade 3 or higher, 2.5% vs. 2%).
The FDA is expected to make a decision on approval of the NSCLC indication by Feb. 28.