The preliminary results of experimental drug candidate REGN2810 are positive. A study carried out on the checkpoint inhibitor with a primary target on PD-1 (programmed death 1) was carried out as a joint effort by Regeneron Pharmaceuticals Inc (NASDAQ:REGN) and Sanofi SA (ADR) (NYSE:SNY).
Patients with advanced cutaneous squamous cell carcinoma (CSCC) were the subjects of the Phase 1 trial of REGN2810, which demonstrated overall response rate (ORR) of 46.2%. This was 12 of 26 patients and it also recorded a disease control rate (DCR) of 69.2% – 18 of 26 patients.
But the median progression-free survival and overall survival were not reached
The data presented American Society of Clinical Oncology (ASCO) Annual meeting was from two cohorts. Patients were given a 3mg/kg dose through intravenous infusion every two weeks and for over 30 minutes. However, despite positive results on CSCC patients, the REGN2810 treatment failed to reach the cutoff point in the median progression-free survival and overall survival.
There was progressive disease in one patient during treatment while another two passed away over the course of the trial. Nonetheless, the deaths were unrelated to REGN2810. Ten patients were enrolled in one expansion cohort (Cohort 7) while another 16 and particularly those suffering from locally or regionally advanced CSCC were enrolled a second expansion cohort (Cohort 8).
The development of a combination therapy
With the promising results of the PD-1 pathway, it is important to establish safety and efficacy of the treatment. That said, there is an ongoing exploration of REGN2810 as a monotherapy for multiple cancers. It is also being developed as an immunotherapy in combination with REGN3767 and will be targeting the checkpoint inhibitor LAG-3.
The study presenter who is also Senior Clinical Investigator at South Texas Accelerated Research Therapeutics, Kyriakos P. Papadopoulos acknowledges “Cutaneous squamous cell carcinoma or CSCC is the second deadliest skin cancer after melanoma, according to the most recent data available.”
Papadopoulos further points out at the limitation of treatments and non-established standards of care and particularly for those in advanced stages of CSCCC. It is worth noting that CSCC has one of the highest mutation rates reported for any cancers. Meanwhile, Regeneron’s stock closed at $480.26 a fall of $0.17 or 0.04%.
