Approval of Sanofi and Regeneron’s cemiplimab (REGN-2810), a programmed cell death protein 1 (PD-1) checkpoint inhibitor, is expected in cutaneous squamous cell carcinoma (CSCC) from the FDA in October 2018 and the European Medicines Agency (EMA) in Q1 2019.
Five PD-1 or programmed cell death ligand 1 (PD-L1) inhibitors – Bristol-Myers Squibb’s (BMS) Opdivo (nivolumab), Merck Sharp & Dohme’s (MSD’s) Keytruda (pembrolizumab), Roche’s Tecentriq (atezolizumab), AstraZeneca’s Imfinzi (durvalumab), and Pfizer and Merck KGaA’s Bavencio (avelumab) – are already approved in a growing number of indications, leaving Sanofi and Regeneron lagging behind their big pharma competitors.
Sanofi and Regeneron are seeking to begin their campaign in less crowded indications by aiming for a first approval in CSCC, which does not yet have any marketed checkpoint inhibitors.
Pivotal data from the Phase II, single-arm EMPOWER-CSCC 1 study in metastatic CSCC and locally advanced patients who are not candidates for surgery, as well as from the CSCC expansion cohorts of the Phase I trial, have been filed with the US and European regulatory agencies. Approximately 50% of patients in both studies achieved complete or partial responses, and the estimated 12-month progression-free survival and overall survival were 53% and 81%, respectively. These data are likely to result in approval for cemiplimab, since responses with chemotherapy, the current standard of care, are moderate and there are no approved treatments for patients once surgery is no longer an option.
Cemiplimab would face challenges in successfully eroding market share from other products if it entered the market as a monotherapy in indications where Keytruda, Opdivo and the other checkpoint agents are already approved. These challenges are reflected in Sanofi’s clinical trial program, which could allow the company first-mover advantage in a number of other indications that have also not yet seen the entry of checkpoint agents. Cemiplimab is in Phase III development for cervical cancer and basal cell carcinoma, as well as Phase II development for other cancers including glioblastoma multiforme, ovarian and prostate cancers, and acute lymphocytic leukemia.