Addition of Cemiplimab to Platinum-Doublet Chemotherapy Prolongs OS in Advanced NSCLC

Patients with advanced non-small cell lung cancer (NSCLC) treated with cemiplimab (Libtayo) in combination with platinum-doublet chemotherapy saw an improvement in overall survival (OS) in comparison with patients who received chemotherapy alone, meeting the primary end point of the phase 3 EMPOWER-Lung 3 study.¹

Regeneron Pharmaceutical, Inc, the developer of cemiplimab, announced in a press release that the Independent Data Monitoring Committee recommended stopping the trial early during a protocol-specific interim analysis, based on the results observed.

"Libtayo in combination with chemotherapy increased median overall survival to 22 months in patients with advanced non-small cell lung cancer, compared to 13 months with chemotherapy alone," said Miranda Gogishvili, MD, an oncologist at the High Technology Medical Center, University Clinic, in Tbilisi, Georgia and a trial investigator. "Notably, the phase 3 trial enrolled patients with a variety of challenging-to-treat disease characteristics, as well as those with locally advanced disease. These data add to the growing body of evidence supporting Libtayo in advanced non-small cell lung cancer, which also includes the pivotal results for Libtayo monotherapy in cases of high PD-L1 expression."

Topline data from 466 patients with advanced NSCLC showed that cemiplimab in combination with chemotherapy reduced the risk of death by 29% compared to chemotherapy alone in the study subjects (HR, 0.71; 95% CI, 0.53-0.93; P = .014). The median OS observed with cemiplimab was 22 months (95% CI, 16 months to not evaluable) versus 13 months (95% CI, 12-16 months) with chemotherapy.

There were no new safety signals observed during the analysis. Further detail on the study results will be presented during an upcoming medical meeting.

The EMPOWER-Lung 3 study enrolled patients with squamous and nonsquamous advanced NSCLC irrespective of PD-L1 expression. All patients included in the study were negative for ALK, EGFR, and ROS1 mutation, and either had either previously untreated metastatic or locally advanced disease and were not eligible to receive chemoradiation. The other requirements for receiving treatment in the study were having an ECOG performance status of 1 or lower and a life expectancy of at least 3 months.^1,2

Patients in the study were randomized 2:1 to receive either cemiplimab with chemotherapy or chemotherapy alone. A total of 312 patients were included in the cemiplimab arm, and were treated with a 350 mg dose by intravenous infusion every 3 weeks for 108 weeks in combination with platinum-doublet chemotherapy every 3 weeks for 4 cycles. The other 154 patients received matching placebo plus chemotherapy. In addition to OS, EMPOWER-Lung 3 is investigating progression-free survival, objective response rate, duration of response, best overall response, the incidence of treatment-emergent adverse events, and the incidence of dose-limiting toxicities as secondary end points.¹

Baseline screening showed that, of the 466 patients included, 30% had tumors with <1% PD-L1 expression, tumors had 1% to 49% PD-L1 expression in 38% of the study population, and 33% of patients had tumors with ≥50% PD-L1 expression.

Cemiplimab, a human monoclonal antibody that targets T-cell immune checkpoint receptor PD-1, is also being investigated for the treatment of advanced cervical cancer, as well as other solid tumor and hematologic cancers in clinical trial settings.

_References:

_{1. Phase 3 trial of Libtayo® (cemiplimab-rwlc) combined with chemotherapy stopped early due to significant improvement in overall survival in patients with first-line advanced non-small cell lung cancer. News release. Regeneron Pharmaceuticals, Inc. August 5, 2021. Accessed August 5, 2021. https://bit.ly/3Acasdh}

_{2. Combinations of cemiplimab (anti-pd-1 antibody) and platinum-based doublet chemotherapy in patients with lung cancer. Clinicaltrials.gov. Accessed August 5, 2021. https://bit.ly/3Ckbcib}