Topline results find PD-1 inhibitor bests platinum chemotherapy

Regeneron/Sanofi, makers of the PD-1 inhibitor cemiplimab (Libtayo), halted a phase III trial of the drug in patients with stage III/IV non-small cell lung cancer (NSCLC) after an interim analysis by an independent Data Monitoring Committee found that first-line monotherapy with the drug decreased the risk of death by 32.4% compared to platinum-based chemotherapy.

“[Cemiplimab] decreased the risk of death by 32.4% (HR=0.676; CI: 0.525-0.870, P=0.002), compared to platinum-doublet chemotherapy, despite a third of patients entering the trial within the past six months and all chemotherapy patients being able to crossover to [cemiplimab] if their disease progressed,” the drug-makers said in a press release. “The data will form the basis of regulatory submissions in the U.S. and European Union (EU) in 2020.” Cemiplimab is currently FDA approved for treatment of adults with metastatic cutaneous squamous cell carcinoma, or locally advanced cutaneous squamous-cell carcinoma (CSCC).

The open-label, randomized, multi-center trial enrolled 712 patients with NSCLC, all of whom tested positive for PD-L1 in ≥50% of tumor cells. The patients had locally advanced disease and were either not candidates for surgical resection “or definitive chemoradiation or had progressed after treatment with definitive chemoradiation, or previously untreated metastatic NSCLC (Stage IV). The trial offers the largest data set from a pivotal trial currently available for this patient population,” the company statement said.

Patients received either 350 mg cemiplimab every three weeks for up to 108 weeks or platinum-doublet chemotherapy for 4 to 6 cycles. The primary endpoints were overall survival and progression-free survival, and secondary endpoints included response rate, duration of response, and quality of life.

“The trial was designed to reflect current and emerging treatment paradigms. Inclusion criteria allowed patients with NSCLC that had: controlled hepatitis B, hepatitis C, or HIV; pre-treated and stable brain metastases; and/or locally advanced disease that had progressed on definitive chemoradiation. Patients whose disease progressed in the trial were able to change their therapy: those in the chemotherapy arm were allowed to crossover into the [cemiplimab] arm, while those in the [cemiplimab] arm were allowed to combine [cemiplimab] treatment with four to six cycles of chemotherapy.”

In releasing the topline results, the companies said full trial data would be presented at a future medical meeting. The American Society of Clinical Oncology’s annual meeting, using a virtual meeting format, is slated for May 29-31, but it is not known if cemiplimab data will be presented at that time.

Peggy Peck, Editor-in-Chief, BreakingMED™

Cat ID: 116

Topic ID: 78,116,730,116,117,122,24,935,192,65,925