Positive pivotal data for Libtayo® (cemiplimab) monotherapy in locally advanced basal cell carcinoma featured as a late-breaking presentation at ESMO

• Libtayo is the first investigational medicine to show a clinical benefit in advanced basal cell carcinoma following treatment with a hedgehog inhibitor in a prospective trial
• 31% objective response rate seen in trial patients, and an estimated 85% of responses were ongoing at one year

PARIS and TARRYTOWN, N.Y. – September 18, 2020 - Positive results from the pivotal Phase 2 trial for the PD-1 inhibitor Libtayo® (cemiplimab) in patients with locally advanced basal cell carcinoma (BCC) who had progressed on or were intolerant to hedgehog inhibitor (HHI) therapy were shared in a late-breaking presentation at the European Society for Medical Oncology (ESMO) Virtual Congress 2020. 

The data will form the basis of regulatory submissions, including in the U.S. and European Union.

“Advanced basal cell carcinoma can be an unrelenting, highly disfiguring disease, and there are no approved treatment options once a patient progresses on or becomes intolerant to hedgehog inhibitors,” said Alexander Stratigos, M.D., Professor of Dermatology at the University of Athens Medical School at Andreas Sygros Hospital and a trial investigator. “This is the first time a prospective trial of an investigational medicine has shown a clinical benefit in this patient population, and the Libtayo data provide hope for this difficult-to-treat cancer.”

Per independent central review, the objective response rate (ORR) was 31% among Libtayo-treated patients (n=84; 95% confidence interval [CI]: 21-42%), with a median follow-up of 15 months (range: 1-25 months). This included a 6% (n=5) complete and 25% (n=21) partial response rate. This is an increase from the ORR shared in May and includes two responses that were confirmed after the initial data analysis. Responses were seen regardless of baseline PD-L1 expression in tumor cells.

As of data cut-off, the median duration of response and median overall survival had not yet been reached. At one-year, 85% of responses were ongoing (95% CI; 61-95%), the probability of progression-free survival was 57% (95% CI: 44-67%), and the probability of overall survival was 92% (95% CI: 84-97%), according to Kaplan-Meier estimates.

No new Libtayo safety signals were observed. The most common treatment-related adverse events (AEs) were fatigue (25%, n=21), pruritus (14%, n=12) and asthenia (14%, n=12). Grade 3 or higher treatment-related AEs that occurred in at least 2 patients were colitis (5%, n=4), fatigue and adrenal insufficiency (2%, n=2 each). Fourteen patients (17%) discontinued treatment due to treatment-emergent AEs.

Libtayo is being jointly developed by Regeneron and Sanofi under a global collaboration agreement. The use of Libtayo to treat advanced BCC is investigational and has not been fully evaluated by any regulatory authority.

About the Pivotal BCC trial

In this ongoing, global Phase 2 trial, two cohorts of patients were studied: locally advanced BCC and metastatic BCC. All patients received Libtayo 350 mg intravenously every three weeks for up to 93 weeks or until disease progression. The primary endpoint is ORR, and key secondary endpoints include overall survival, progression free survival, duration of response, safety and tolerability. The median duration of response and median overall survival were estimated using Kaplan-Meier analyses. Detailed interim metastatic BCC data are planned for presentation at an upcoming medical meeting.

About BCC

BCC is a common type of non-melanoma skin cancer. While the vast majority of BCCs are caught early and easily cured with surgery and radiation, a small proportion of tumors can become advanced and penetrate deeper into surrounding tissues (locally advanced) or spread to other parts of the body (metastatic), which is more difficult to treat. In the U.S. alone, approximately 2 million new cases of BCC will be diagnosed every year, 20,000 U.S. patients will have advanced BCC and 3,000 patients will die of this disease.

About Libtayo

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.

Libtayo is the first immunotherapy approved in the U.S., EU, and other countries for adults with metastatic cutaneous squamous cell carcinoma (CSCC) or locally advanced CSCC who are not candidates for curative surgery or curative radiation. In the U.S., the generic name for Libtayo in its approved indication is cemiplimab-rwlc, with rwlc as the suffix designated in accordance with Nonproprietary Naming of Biological Products Guidance for Industry issued by the U.S. Food and Drug Administration. Outside of the U.S., the generic name for Libtayo in its approved indication is cemiplimab.

The extensive clinical program for Libtayo is focused on difficult-to-treat cancers. In skin cancer, this includes trials in adjuvant and neoadjuvant CSCC in addition to the pivotal trial in advanced BCC. Libtayo is also being investigated in pivotal trials in NSCLC and cervical cancer, as well as in trials combining Libtayo with either conventional or novel therapeutic approaches for both solid tumors and blood cancers. These potential uses are investigational, and their safety and efficacy have not been evaluated by any regulatory authority.

About Regeneron Pharmaceuticals, Inc.

Regeneron (NASDAQ: REGN) is a leading biotechnology company that invents life-transforming medicines for people with serious diseases. Founded and led for over 30 years by physician-scientists, our unique ability to repeatedly and consistently translate science into medicine has led to seven FDA-approved treatments and numerous product candidates in development, all of which were homegrown in our laboratories. Our medicines and pipeline are designed to help patients with eye diseases, allergic and inflammatory diseases, cancer, cardiovascular and metabolic diseases, pain, infectious diseases and rare diseases.

Regeneron is accelerating and improving the traditional drug development process through our proprietary VelociSuite^® technologies, such as VelocImmune which uses unique genetically-humanized mice to produce optimized fully-human antibodies and bispecific antibodies, and through ambitious research initiatives such as the Regeneron Genetics Center, which is conducting one of the largest genetics sequencing efforts in the world.

For additional information about the company, please visit www.regeneron.com or follow @Regeneron on Twitter.