"...These important new results further demonstrate Libtayo’s potential in patients with difficult-to-treat, non-melanoma skin cancers."
In patients with advanced basal cell carcinoma (BCC), cemiplimab (Libtayo) demonstrated clinically meaningful and durable responses, showing a potential option for treatment of patients for whom no approved treatments exist. Topline data from a pivotal, single-arm, open-label trial of cemiplimab in patients with BCC who had progressed on or were intolerant to prior hedgehog pathway inhibitor therapy were announced in a press release from co-developer Sanofi.
“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,” said Peter C. Adamson, MD, global head of oncology development at Sanofi, in a statement. “We are continuing to address this unmet need by first bringing Libtayo 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 Libtayo’s potential in patients with difficult-to-treat, non-melanoma skin cancers.”
Regulatory submission for cemiplimab from Sanofi and co-developer Regeneron are planned for later this year.
The primary end point, objective response rate (ORR), was 29% (95% CI, 19%-40%) in the 84 patients with locally advanced disease. The estimated duration of response (DOR) for this group of patients was over 1 year in 85% of responders. Durable disease control rate (DCR), was defined as response or stable disease continuing for a minimum of 6 months. Durable DCR was evaluated in patients. In patients with locally advanced disease, the DCR was 60% (95% CI, 48%-70%).
Twenty-eight patients with metastatic disease were assessed in a preliminary analysis. The ORR in this group was 21% (95% CI, 8%-41%) and the DOR was estimated to be above 1 year in 83% of responders. The durable DCR for patients with metastatic disease was 46% (95% CI, 28%-66%).
All data in the study were assessed by an independent central review. Follow-up continues in the study for both groups of patients.
“Libtayo 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, Translational and Clinical Sciences, Oncology at Regeneron, said in a press release. “These data in advanced BCC provide the third instance where Libtayo 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.”
A total of 132 patients were evaluated for safety, 84 of whom had locally advanced disease and 48 of whom had metastatic disease. Overall, no new safety signals were seen. Adverse events (AEs) occurred 95% of participants and there were serious AEs observed in 32% of patients. Thirteen percent of patients discontinued treatment with cemiplimab due to an AE. In the locally advanced group, 10 patients died during the study, as did 9 patients with metastatic BCC. Deaths in the study were not considered to be treatment related.
Participants in the ongoing study (NCT03132636) are receiving cemiplimab 350 mg intravenously every 3 weeks. Treatment continues for up to 93 weeks or until disease progression, unacceptable toxicity, withdrawal of consent, or confirmed complete response. The secondary end points of the study are overall survival, progression-free survival, DOR, safety, and quality of life.
Further findings from the trials will be presented at an upcoming medical meeting.
Libtayo® (cemiplimab) shows clinically meaningful and durable responses in second-line advanced basal cell carcinoma [news release]. Paris, France and Tarrytown, New York: Sanofi; May 5, 2020. https://bit.ly/2L2Zyip. Accessed May 5, 2020.