Oral presentation provides first REGN2810 data in patients with advanced cutaneous squamous cell carcinoma (CSCC)

BRIDGEWATER, NJ and TARRYTOWN, NY, USA I June 4, 2017 I Sanofi and Regeneron Pharmaceuticals, Inc. today announced positive preliminary results with investigational REGN2810, a checkpoint inhibitor targeting PD-1 (programmed death 1), in patients with advanced cutaneous squamous cell carcinoma (CSCC). The data, pooled from two expansion cohorts of the REGN2810 Phase 1 trial, will be presented today at the 2017 American Society of Clinical Oncology (ASCO) Annual Meeting in Chicago during an oral presentation (Abstract #9503). REGN2810 is also being investigated in EMPOWER-CSCC 1, an ongoing Phase 2, potentially pivotal, single-arm, open label clinical trial that is currently enrolling advanced CSCC patients.

Treatment with REGN2810 led to an investigator-assessed overall response rate (ORR) of 46.2 percent (12 of 26 patients, including 2 complete responses, 9 partial responses and 1 unconfirmed partial response) and a disease control rate (DCR) of 69.2 percent (18 of 26 patients, including 12 ORR and 6 stable disease). The median progression free survival and overall survival were not reached at the data cutoff date with a median follow up of 6.9 months (range: 1.1 to 13.8 months; ongoing). One patient experienced progressive disease during treatment with REGN2810 after the initial response, and two patients were not evaluable due to death considered unrelated to REGN2810. Ten patients remain in response as of the data cutoff date (range 8 to 40 weeks duration of response).

The most common treatment-related adverse event of any grade was fatigue (23.1 percent). All grade 3 or higher adverse events occurred once and included arthralgia (3.8 percent), maculopapular rash (3.8 percent), asthenia (3.8 percent), aspartate aminotransferase (AST) elevation (3.8 percent) and alanine aminotransferase (ALT) elevation (3.8 percent).

“Cutaneous squamous cell carcinoma or CSCC is the second deadliest skin cancer after melanoma, according to the most recent data available,” said Kyriakos P. Papadopoulos, M.D., Senior Clinical Investigator at South Texas Accelerated Research Therapeutics (START) and the study presenter.  “There are limited treatments and no established standards of care for advanced stages of this disease.  CSCC has one of the highest mutation rates reported for any cancers, likely contributing to the study findings, which represent a high responder rate to a PD-1 antibody in a solid tumor cancer. These results are promising and suggest the PD-1 pathway is an important therapeutic target in these patients.” 

No apparent association between the objective response and level of PD-L1 (programmed death ligand 1) expression was found. PD-L1 expression by immunohistochemistry (22C3 clone, Dako) was performed in tumor cells for 21 expansion cohort patients, with 81 percent of patients (17 of 21) having greater than or equal to 1 percent positive PD-L1 expression. Additional correlative studies are in process. 

This Phase 1 study was designed with an initial dose-escalation portion followed by multiple expansion cohorts that were opened to investigate safety and antitumor activity in specific patient populations.  These results are from 10 patients with distantly metastatic CSCC who were enrolled in one expansion cohort (Cohort 7) and 16 patients with inoperable (unresectable) locally or regionally advanced CSCC who were enrolled in a second expansion cohort (Cohort 8). All expansion cohort patients were treated with 3 mg/kg doses of REGN2810 by intravenous infusion over 30 minutes every two weeks for up to 48 weeks.

REGN2810 is a human, monoclonal antibody targeting the checkpoint inhibitor PD-1 and is being jointly developed by Regeneron and Sanofi under a global collaboration agreement. REGN2810 is currently being explored as a monotherapy for multiple cancers – including cutaneous squamous cell carcinoma (CSCC), basal cell carcinoma (BCC) and non-small cell lung cancer (NSCLC) – as well as in combination with REGN3767, another investigational immunotherapy targeting the checkpoint inhibitor LAG-3 (lymphocyte-activation gene 3).

REGN2810 and REGN3767 are currently under clinical development, and their safety and efficacy have not been fully evaluated by any regulatory authority.

About CSCC

CSCC is the second most common type of skin cancer in the United States. Although CSCC has a good prognosis when caught early and removed with surgery, it can prove especially aggressive when it progresses to advanced stages. Patients at this stage can be disfigured due to multiple surgeries to remove skin-surface tumors on the head, neck and other parts of the body. CSCC is responsible for the most deaths among non-melanoma skin cancer patients. 

About Sanofi

Sanofi, a global healthcare leader, discovers, develops and distributes therapeutic solutions focused on patients’ needs. Sanofi is organized into five global business units: Diabetes and Cardiovascular, General Medicines and Emerging Markets, Sanofi Genzyme, Sanofi Pasteur and Consumer Healthcare. Sanofi is listed in Paris (EURONEXT: SAN) and in New York (NYSE: SNY).

About Regeneron Pharmaceuticals, Inc.

Regeneron (NASDAQ: REGN) is a leading science-based biopharmaceutical company that discovers, invents, develops, manufactures and commercializes medicines for the treatment of serious medical conditions. All Regeneron commercialized medicines were discovered and developed by our own scientists, including therapies for eye diseases, high LDL cholesterol, atopic dermatitis, rheumatoid arthritis, and a rare inflammatory condition. Regeneron also has product candidates in development in other areas of high unmet medical need, including asthma, pain, cancer and infectious diseases.

Regeneron invented the leading VelociSuite® technologies, which are a suite of complementary genetics-based technologies that accelerate, improve and disrupt the traditional drug discovery and development process and established the Regeneron Genetics Center, one of the largest genetic sequencing efforts in the world. For additional information about the company, please visit www.regeneron.com or follow @Regeneron on Twitter.

SOURCE: Sanofi Genzyme