FDA Accepts for Review Libtayo (cemiplimab-rwlc) in Combination with Chemotherapy for First-line Treatment of Advanced NSCLC

Regeneron Pharmaceuticals, Inc. announced that the U.S. Food and Drug Administration (FDA) has accepted for review the supplemental Biologics License Application (sBLA) for PD-1 inhibitor Libtayo (cemiplimab-rwlc) in combination with chemotherapy as first-line treatment in advanced non-small cell lung cancer (NSCLC). The target action date for the FDA decision is September 19, 2022.

The sBLA is supported by results from a randomized, multicenter Phase 3 trial that investigated Libtayo in combination with a physician’s choice of platinum-doublet chemotherapy (Libtayo combination), compared to platinum-doublet chemotherapy alone. Enrolled patients (n=466) had locally advanced or metastatic NSCLC, irrespective of PD-L1 expression level or tumor histology, and with no ALK, EGFR or ROS1 aberrations. A regulatory filing has also been recently submitted to the European Medicines Agency.

The Phase 3 trial supporting the sBLA was stopped early after the Libtayo combination demonstrated a significant overall survival improvement compared to chemotherapy alone. Results were presented at the European Society for Medical Oncology Virtual Congress in 2021. Among patients in the Libtayo combination (n=312) and chemotherapy alone (n=154) groups, treatment discontinuations due to adverse events (AEs) occurred in 5% and 3% of patients, respectively. Immune-mediated AEs occurred in 19% of patients in the Libtayo combination group.

Notably, the Phase 3 trial was designed to include baseline characteristics seen in everyday clinical practice. Among those enrolled, 43% had tumors with squamous histology, 67% had tumors with <50% PD-L1 expression, 15% had inoperable locally advanced disease not eligible for definitive chemoradiation, and 7% had pretreated and clinically stable brain metastases. In addition, 84% of patients had an ECOG 1 performance status, which indicates the presence of cancer-related symptoms. ECOG performance status assesses patient ability to conduct daily living activities and prognosis on a scale of increasing severity ranging from 0 (no symptoms) to 5 (death).

In 2021, Libtayo was approved in the U.S. and European Union as first-line monotherapy treatment for adult patients with advanced NSCLC whose tumors have high PD-L1 expression (tumor proportion score ≥50%), as determined by an FDA-approved test. Patients must either have metastatic or locally advanced tumors that are not candidates for surgical resection or definitive chemoradiation, and the tumors must not have EGFR, ALK or ROS1 aberrations.

Libtayo, which was invented using Regeneron’s proprietary VelocImmune technology, is being jointly developed by Regeneron and Sanofi under a global collaboration agreement. The use of Libtayo in combination with chemotherapy for advanced NSCLC is investigational, and its safety and efficacy have not been fully evaluated by any regulatory authority.