Cemiplimab Shows Promise for Patients with Advanced Basal Cell Carcinoma

Cemiplimab showed clinically meaningful and durable responses in this group of patients for whom there are no currently approved treatments.

Topline data from the pivotal, single-arm, open-label trial of cemiplimab (Libtayo) in patients with advanced basal cell carcinoma (BCC) who had progress on or were intolerant to prior hedgehog pathway inhibitor (HHI) therapy were announced by Sanofi and Regeneron, the developers of the PD-1 inhibitor. 

Cemiplimab showed clinically meaningful and durable responses in this group of patients for whom there are no currently approved treatments. The companies indicated that they anticipate regulatory submissions sometime in 2020.

BCC is the second non-melanoma skin cancer for which cemiplimab has demonstrated first-in-class data, as the agent was initially approved in the US, EU, and other countries for advanced cutaneous squamous cell carcinoma (CSCC) or locally advanced CSCC who are not candidates for curative surgery or curative radiation. 

“While PD-1 inhibitors have transformed the outlook for many patients with melanoma, progress for patients with non-melanoma skin cancers has not been as rapid,” Peter C. Adamson, MD, global head of oncology development at Sanofi, said in a press release. “We are continuing to address this unmet need by first bringing [cemiplimab] to patients with advanced cutaneous squamous cell carcinoma, and now, with this second trial, as a potential therapy for patients with advanced basal cell carcinoma. These important new results further demonstrate [cemiplimab’s] potential in patients with difficult-to-treat, non-melanoma skin cancers.”

In this ongoing phase II trial, patients received 350 mg of cemiplimab every 3 weeks for up to 93 weeks or until disease progression, unacceptable toxicity, withdrawal of consent, or confirmed complete response. The primary endpoint is overall response rate (ORR), and key secondary endpoints include overall survival, progression-free survival, duration of response (DOR), safety, and quality of life. 

In the trial, the ORR for 84 patients with locally advanced disease was 29% (95% CI, 19%-40%), with an estimated DOR surpassing 1 year in 85% of responders. The durable disease control rate (DCR) was 60% (95% CI, 48%-70%). 

In a preliminary analysis of 28 patients with metastatic disease, the ORR was 21% (95% CI, 8%-41%), with an estimated DOR exceeding 1 year in 83% of responders. The durable DCR was 46% (95% CI, 28%-66%). Notably, all data reported were assessed by an independent central review committee. Further, data are expected to continue to evolve with further follow-up across both patient groups.

“[Cemiplimab] is being investigated as a monotherapy treatment and as a foundation therapy for combinations with novel therapeutic approaches being developed by Regeneron and our collaborators,” Israel Lowy, MD, PhD, senior vice president of Translational and Clinical Sciences, as well as Oncology, at Regeneron, said in a press release. “These data in advanced BCC provide the third instance where [cemiplimab] monotherapy has demonstrated robust and clinically meaningful outcomes in advanced cancer and follows last week’s announcement in advanced non-small cell lung cancer where the pivotal trial was stopped early for positive overall survival.”

Cemiplimab is also being investigated in potentially registrational phase III trials in non-small lung cancer and cervical cancer, as well as in trials combining cemiplimab with novel therapeutic approached in both solid tumors and blood cancers. 

The use of cemiplimab to treat advanced BCC remains investigational, and the safety and efficacy have not yet been evaluated by any regulatory authority.


Libtayo® (cemiplimab) shows clinically meaningful and durable responses in second-line advanced basal cell carcinoma [news release]. Paris and Tarrytown, NY. Published May 5, 2020. sanofi.com/en/media-room/press-releases/2020/2020-05-05-07-00-00. Accessed May 5, 2020.