NSCLC Drug Trial Stopped Early After Strong Survival Results

The phase 3 trial of Sanofi and Regeneron’s PD-1 inhibitor Libtayo (cemiplimab-rwlc) in combination with a platinum-based chemotherapy combination was stopped early after meeting its overall survival (OS) primary endpoint in patients with advanced nonsmall cell lung cancer (NSCLC).

As a result, Sanofi and Regeneron plan regulatory submissions in the United States and European Union.

“Libtayo in combination with chemotherapy increased median overall survival to 22 months in patients with advanced nonsmall cell lung cancer, compared with 13 months with chemotherapy alone,” Miranda Gogishvili, M.D., trial investigator and an oncologist at the High Technology Medical Center, University Clinic, in the country of Georgia, said a statement.

Additionally, in the top-line initial analysis of 466 patients, combining Libtayo with chemotherapy reduced the risk of death by 29% compared with chemotherapy alone.

Notably, the phase 3 trial enrolled patients with a variety of challenging-to-treat disease characteristics, as well as those with locally advanced disease, Gogishvili said. “These data add to the growing body of evidence supporting Libtayo in advanced nonsmall cell lung cancer, which also include the pivotal results for Libtayo monotherapy in cases of high PD-L1 expression.”

No new Libtayo safety signals were identified in this analysis, and additional detailed efficacy and safety data will be presented at an upcoming medical meeting, the companies said said.

Lung cancer is the leading cause of cancer death worldwide. In 2020, an estimated 225,000 new cases were diagnosed in the US. Around 84% of all lung cancers are NSCLC, with 75% of these cases diagnosed in advanced stages, according to Sanofi and Regeneron.

Libtayo is a fully human monoclonal antibody targeting the immune checkpoint receptor PD-1 on T-cells. By binding to PD-1, Libtayo has been shown to block cancer cells from using the PD-1 pathway to suppress T-cell activation, according to Sanofi and Regeneron.

The therapy is currently being investigated in advanced cervical cancer, as well as in trials combining the drug with either conventional or novel therapeutic approaches for other solid tumors and blood cancers. “These potential uses are investigational, and their safety and efficacy have not been evaluated by any regulatory authority,” Sanofi and Regeneron said.

Libtayo is approved as a first treatment for NSCLC in patients who have high PD-L1 expression with no EGFR, ALK, or ROS1 mutations. It is also indicated to treat cutaneous squamous cell carcinoma and basal cell carcinoma.