Libtayo® (cemiplimab) Shows 5-Year Survival Benefit in Advanced NSCLC

Regeneron Pharmaceuticals, Inc. has revealed five-year results from the final pre-specified overall survival analysis of the Phase 3 EMPOWER-Lung 1 trial. This study compared Libtayo® (cemiplimab) monotherapy with chemotherapy as an initial treatment for adults with advanced non-small cell lung cancer (NSCLC). These patients exhibited at least 50% PD-L1 expression and showed no EGFR, ALK, or ROS1 aberrations. The findings will be discussed in an oral session at the IASLC 2024 World Conference on Lung Cancer (WCLC).

Ana Baramidze, MD, PhD, Head of Clinical Research Department at Todua Clinic in Tbilisi, Georgia, emphasized the significance of the five-year results, which highlight the durable survival benefits and efficacy of Libtayo. According to Dr. Baramidze, the data offer valuable insights for doctors treating patients who progress on PD-1 inhibitor monotherapy. She noted that EMPOWER-Lung 1 is unique in evaluating the survival rate when chemotherapy is added to a PD-1 inhibitor post-progression.

At the five-year follow-up, Libtayo showed superior results compared to chemotherapy in patients with confirmed PD-L1 expression of 50% or more. The benefits were consistent with previous analyses. The study focused on a subset of the randomized population, excluding patients whose tumors could not be retested or had less than 50% PD-L1 expression.

Patients who experienced progression had the option to switch their therapy. Those initially assigned to Libtayo could add four cycles of chemotherapy. Among these patients, the addition of chemotherapy resulted in a median overall survival (OS) of 15 months, median progression-free survival (PFS) of 7 months, and an overall response rate (ORR) of 28%.

The exploratory subgroup analysis of EMPOWER-Lung 1 demonstrated a direct correlation between PD-L1 expression levels and survival benefits among Libtayo patients. Those with PD-L1 expression levels of 90% or more experienced the most significant benefits, with a median OS of 39 months and a median PFS of 15 months. This correlation was not observed in patients treated with chemotherapy.

No new safety concerns were identified during the five-year follow-up. Among the evaluable patients, adverse events (AEs) of any grade occurred in 93% of Libtayo patients and 96% of chemotherapy patients. Common AEs for Libtayo included anemia, decreased appetite, fatigue, pneumonia, arthralgia, back pain, dyspnea, cough, and pruritus. Serious AEs led to treatment discontinuation in 9% of Libtayo patients.

For the 75 Libtayo patients who received additional chemotherapy after disease progression, 89% experienced AEs, with common ones being anemia, alopecia, diarrhea, nausea, neutropenia, and asthenia. Serious AEs led to discontinuation of treatment in 5% of these patients.

Other presentations regarding Regeneron's oncology portfolio and pipeline were also scheduled at WCLC. The potential use of adding chemotherapy to Libtayo following disease progression remains investigational, and its safety and efficacy have not been fully evaluated.

Regeneron is committed to transforming cancer treatment through innovative therapies and collaborations. Libtayo, a fully human monoclonal antibody targeting PD-1, has been developed using Regeneron's VelocImmune® technology. Libtayo is approved for various advanced cancers including basal cell carcinoma, cutaneous squamous cell carcinoma, non-small cell lung cancer, and cervical cancer in specific regions.

Regeneron's extensive clinical program for Libtayo focuses on difficult-to-treat cancers. The company leverages advanced technologies and collaborations to pioneer potential treatments for solid tumors and blood cancers.