The U.S. Food and Drug Administration granted approval of a drug that is the first immunotherapy treatment indicated for patients diagnosed with advanced basal cell carcinoma (BCC) who had already been treated with a hedgehog pathway inhibitor (HHI) or are not able to use HHI. Called cemiplimab-rwlc (Libtayo, Regeneron), the drug is a programmed cell death ligand-1 (PD-1) inhibitor and according to recent news was the first of this class to exhibit clinical benefit in individuals suffering from advanced BCC post HHHI therapy in a pivotal trial. This drug actually blocks the cancer cells from using PD-1 pathway to suppress T cell activation. Trial investigator Karl Lewis, MD, declared in a press release, “Today’s FDA approval of Libtayo will change the treatment paradigm for patients with advanced basal cell carcinoma.”
The approval was based on an open-label, multicenter, non-randomized Phase 2 clinical trial including patients with unresectable locally advanced BCC or metastatic BCC; this represented the largest prospective clinical trial among this patient cohort. Involving 132 participants, 112 of them were included in the efficacy analysis. As was mentioned in the introduction patients in this study either progressed while on HHI therapy; or failed to exhibit an objective response post 9 months on HHI therapy; or were not able to use the HHI therapy.
What was the primary endpoint?
Using confirmed objective response rate (ORR) as well as a duration of response (DOR) for an important secondary endpoint, confirmed ORR was 21% for patients with metastatic BCC and 29% for patients with locally advanced BCC. Of patients with locally advanced BCC 6% achieved a complete response (CR) while no patients in the metastatic BCC cohort achieved CR. 100% of patients with metastatic BCC achieved a DOR of 6 months or longer compared with 79% of those patients with locally advanced BCC.
What about side effects?
Fatigue, musculoskeletal pain, diarrhea, rash, pruritus as well as upper respiratory tract infection was the most common adverse events (AE) reported. 32% of patients experienced serious AEs such as urinary tract infection, colitis, acute kidney injury and others. AEs leading to permanent discontinuation totaled 13% of the patients.
Karl Lewis, MD, professor, division of medical oncology, University of Colorado