Sanofi and Regeneron’s Libtayo trial stops early due to survival improvement

A Phase III trial of Sanofi and Regeneron’s PD-1 inhibitor Libtayo (cemiplimab) in combination with platinum-doublet chemotherapy has been stopped early after meeting its overall survival (OS) primary endpoint in patients with advanced non-small cell lung cancer (NSCLC).

The trial enrolled patients with metastatic or locally advanced disease and tumours with either squamous or non-squamous histology. In initial analysis of 466 patients, combining Libtayo with chemotherapy reduced the risk of death by 29% compared to chemotherapy alone.

This data is planned to form the basis of regulatory submissions to the US Food and Drug Administration (FDA) and European Medicines Agency (EMA), the companies said in a statement.

“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, a trial investigator.

“Notably, the Phase III 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 include the pivotal results for Libtayo monotherapy in cases of high PD-L1 expression,” she added.