The U.S. Food and Drug Administration (FDA) approved cosibelimab-ipdl (Unloxcyt), a PD-L1–blocking antibody, for adults with metastatic or locally advanced cutaneous squamous cell carcinoma who are not candidates for curative surgery or radiation therapy. The approval was granted on December 13, 2024.
Efficacy and Safety
Efficacy was evaluated in Study CK-301-101 (ClinicalTrials.gov identifier NCT03212404), a multicenter, multicohort, open-label trial in 109 patients with metastatic or locally advanced cutaneous squamous cell carcinoma who were not candidates for curative surgery or radiation therapy. Exclusion criteria included active or suspected autoimmune disease; allogeneic transplant within 6 months prior to treatment; prior treatment with anti–PD-1/PD-L1–blocking antibodies or other immune checkpoint inhibitor therapy; uncontrolled or significant cardiovascular disease; Eastern Cooperative Oncology Group performance status 2; or infection with human immunodeficiency virus, hepatitis B, or hepatitis C.
The major efficacy outcome measures were objective response rate and duration of response, as assessed by an independent central review committee according to Response Evaluation Criteria in Solid Tumors version 1.1. For patients with locally advanced cutaneous squamous cell carcinoma with externally visible target lesions not assessable by radiologic imaging, the objective response rate was determined by independent central review assessments of digital photography (World Health Organization criteria). The objective response rate was 47% (95% confidence interval [CI] = 36%–59%) for 78 patients with metastatic cutaneous squamous cell carcinoma and 48% (95% CI = 30%–67%) for 31 patients with locally advanced squamous cell carcinoma. The median duration of response was not reached (range = 1.4+ to 34.1+ months) in patients with metastatic cutaneous squamous cell carcinoma and 17.7 months (range = 3.7+ to 17.7 months) in patients with locally advanced cutaneous squamous cell carcinoma.
Adverse Reactions and Dosage
The most common adverse reactions (≥ 10%) were fatigue, musculoskeletal pain, rash, diarrhea, hypothyroidism, constipation, nausea, headache, pruritus, edema, localized infection, and urinary tract infection.
The recommended dose of cosibelimab is 1,200 mg administered as an intravenous infusion over 60 minutes every 3 weeks until disease progression or unacceptable toxicity.
For full prescribing information for cosibelimab, visit Drugs@FDA.
