Sanofi and Regeneron announced that the phase 3 trial evaluating cemiplimab (Libtayo®) as a potential first-line treatment in patients with locally advanced or metastatic non-small cell lung cancer (NSCLC) was stopped early due to “highly significant improvement” in overall survival.
The open-label, randomized, multicenter trial compared the effects of cemiplimab monotherapy to platinum doublet chemotherapy in 712 patients with advanced NSCLC who tested positive for PD-L1 in ≥50% of tumor cells. Patients were randomized to receive either cemiplimab 350mg intravenously every 3 weeks for up to 108 weeks, or a platinum-based, doublet chemotherapy regimen for 4 to 6 cycles. The trial enrolled a third of the patients within the past 6 months and all patients in the chemotherapy arm were able to crossover to cemiplimab if their disease progressed.
Interim analysis showed that cemiplimab monotherapy was associated with a significant improvement in overall survival (primary end point). Compared with platinum doublet chemotherapy, treatment with cemiplimab reduced the risk of death by 32.4% (HR 0.676; 95% CI, 0.525-0.870; P =.002). The decision to stop the trial was made based on a recommendation from the study’s independent Data Monitoring Committee (DMC). There were no new cemiplimab safety signals identified.
Detailed trial data will be presented at a future medical meeting. The Company plans to use the study data for regulatory submission in 2020.
“This is the largest clinical trial evaluating a PD-1 inhibitor as a first-line monotherapy in patients with advanced non-small cell lung cancer with high PD-L1 expression.” said John Reed, MD, PhD, Global Head of Research and Development at Sanofi. “The positive results are extremely encouraging, and we look forward to advancing a potential new treatment option for these patients.”
Cemiplimab, a programmed death receptor-1 (PD-1) blocking antibody, is marketed under the brand name Libtayo and is currently indicated for the treatment of metastatic cutaneous squamous cell carcinoma (CSCC) or locally advanced CSCC in adult patients who are not candidates for curative surgery or curative radiation.