ESMO late-breaking data show Libtayo and chemotherapy first-line treatment combination significantly improved overall survival in patients with advanced NSCLC.

The trial, which met its primary overall survival (OS) endpoint and all key secondary endpoints, assessed the investigational use of PD-1 inhibitor Libtayo in combination with a physician's choice of platinum-doublet chemotherapy (Libtayo combination) in patients with locally advanced or metastatic non-small cell lung cancer (NSCLC) irrespective of histology and across all PD-L1 expression levels, compared to chemotherapy alone. These results were also achieved in a patient population with varied baseline characteristics and will form the basis of regulatory submissions, including in the U.S. and European Union (EU).

In the overall population, patients treated with the Libtayo combination (n=312) experienced significant improvements compared to those receiving chemotherapy alone (n=154), including a: i.22-month median OS compared to 13 months for chemotherapy, representing a 29% relative reduction in the risk of death (hazard ratio [HR]: 0.71; 95% confidence interval [CI]: 0.53 to 0.93; p=0.014). The 12-month probability of survival was 66% for the Libtayo combination and 56% for chemotherapy. ii. 8-month median progression-free survival (PFS) compared to 5 months for chemotherapy, representing a 46% relative reduction in the risk of disease progression (HR: 0.56; 95% CI: 0.44 to 0.70; p<0.0001). iii. the 12-month probability of pfs was 38% for the libtayo combination and 16% for chemotherapy. iv.43% objective response rate (orr) compared to 23% for chemotherapy. v. 16-month median duration of response (dor) compared to 7 months for chemotherapy.></0.0001).>

Favorable patient-reported outcomes were also observed. Specifically, the Libtayo combination delayed deterioration in pain symptoms (HR: 0.39; 95% CI: 0.26 to 0.60; nominal p<0.0001) and showed a trend towards delayed deterioration in global health status quality of life (hr: 0.78; 95% ci: 0.51 to 1.19; nominal p="0.248)," compared to chemotherapy. the libtayo combination also improved pain symptoms, compared to chemotherapy (-4.98 difference in baseline changes between treatment groups; 95% ci: -8.36 to -1.60; nominal p="0.004)."></0.0001)>

No new Libtayo safety signals were identified. The median duration of exposure was 38 weeks for the Libtayo combination (n=312) and 21 weeks for chemotherapy (n=153). Adverse events (AEs) of any grade occurred in 96% of patients receiving the Libtayo combination and 94% of patients receiving chemotherapy alone, with 19% and 0% being immune-mediated, respectively. For the Libtayo combination and chemotherapy groups, the most common AEs were anemia (44%, 40%), alopecia (37%, 43%) and nausea (25%, 16%); grade greater than 3 AEs occurring in greater than 5% of patients were anemia (10%, 7%) and neutropenia (both 6%). Treatment discontinuation due to AEs occurred in 5% of patients receiving the Libtayo combination and 3% receiving chemotherapy.

"This Phase III trial was stopped early because Libtayo significantly improved overall survival compared to chemotherapy, a milestone also achieved by our Phase III trial for Libtayo monotherapy as a first-line treatment for advanced non-small cell lung cancer with high PD-L1 expression," said Israel Lowy, M.D., Ph.D., Senior Vice President, Translational and Clinical Sciences, Oncology at Regeneron. "Both trials were designed to reflect everyday clinical practice by allowing for the enrollment of patients with difficult-to-treat disease characteristics. And this is the second Libtayo trial to demonstrate significant improvement in its primary and key secondary endpoints for these patient populations, compared to chemotherapy."

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.