Besties Regeneron, Sanofi Show Off Phase II Skin Cancer Data

Clinical Drug

A few months after Sanofi and Regeneron’s skin cancer drug cemiplimab snagged Breakthrough Therapy Status, the company rolled out impressive topline results from its pivotal Phase II study that continued to show a high response rate in patients. The positive results are spurring the companies to begin seeking approval for the checkpoint inhibitor.

Sanofi and Regeneron are developing the PD-1 inhibitor cemiplimab to treat adult patients with metastatic cutaneous squamous cell carcinoma (CSCC) and adults with locally advanced and unresectable CSCC, the second deadliest skin cancer after melanoma. In the latest results, long-time partners Regeneron and Sanofi said of the 82 patients treated with cemiplimab, 46.3 percent demonstrated an overall response rate. The median duration of response had not yet been reached at the data cut-off point, with 32 of 38 responses ongoing, the companies said. At the time of this analysis, all patients had a minimum follow up of six months.

The latest data is a confirmation of data seen in a Phase I trial. In June, the companies presented early-stage data that showed cemiplimab led to overall response rate of 46.2 percent in CSCC patients. The drug also demonstrated a 69.2 percent disease control rate. The data presented at the American Society of Oncology was pooled from two Phase I cohorts totaling 26 advanced CSCC patients.

The companies said the data from the Phase II trial will form the basis for a rolling Biologics License Application submission to the U.S. Food and Drug Administration, which is expected to be complete in the first quarter of 2018. A submission to the European Medicines Agency (EMA) is also expected to be completed in the first quarter of 2018.

“For patients with CSCC that cannot be cured by surgery or radiation, there are no FDA-approved treatment options, and advanced CSCC is responsible for 3,900 to 8,800 deaths per year in the U.S.,” Israel Lowy, Regeneron’s head of translational science and clinical oncology, said in a statement. “This is the largest prospective study ever conducted in this disease, and we are pleased that many patients were able to achieve deep and durable responses with cemiplimab monotherapy. The high and durable response rates seen in this study are particularly notable given that the study enrolled patients regardless of biomarker status.”

SCC is the second most common type of skin cancer in the United States. It can be fatal to non-melanoma skin cancer patients, Although CSCC has a good prognosis when caught early, and it can prove especially difficult to treat when it progresses to advanced stages. Patients at this stage can be disfigured due to multiple surgeries to remove CSCC tumors on the head, neck and other parts of the body.

The Sanofi and Regeneron developmental partnership is proving to be a valuable one. This year alone the two companies have snagged FDA approval for two jointly-developed drugs. In May, the companies gained approval for rheumatoid arthritis drug Kevzara (sarilumab). Data from a Phase III trial released in March showed that sarilumab outperformed AbbVie’s Humira. In March, the FDA approved Dupixent (dupilumab) for the treatment of adults with moderate-to-severe atopic dermatitis.

If cemiplimab is approved, that could mean big money for the two companies. PD-1 inhibitors like Merck’s Keytruda or Bristol-Myers’ Opdivo have generated more than $2 billion in sales per quarter, according to reports last month.

Back to news