Sun Pharma Reports Durable Responses with UNLOXCYT in Advanced Skin Cancer at ASCO 2026
Key Insights
Sun Pharma will present updated long-term follow-up data for UNLOXCYT (search) (cosibelimab-ipdl (search)) in locally advanced cutaneous squamous cell carcinoma (search) at ASCO 2026, representing the second largest prospective study of its kind.
The study demonstrated a 50% objective response rate with 27% complete responses in 64 patients, with median duration of response not yet reached after over 31 months of follow-up.
The treatment showed a manageable safety profile with only one patient experiencing Grade ≥3 immune-related adverse events, supporting its use in elderly patients with multiple comorbidities.
Sun Pharma announced it will present pivotal long-term follow-up data for UNLOXCYT (search) (cosibelimab-ipdl (search)) in locally advanced cutaneous squamous cell carcinoma (search) (laCSCC) at the 2026 American Society of Clinical Oncology (ASCO) Annual Meeting. The data represents results from the second largest prospective study of laCSCC patients treated with PD-(L)1 monotherapy, demonstrating sustained efficacy and tolerability in this challenging patient population.
Clinical Trial Results Show Sustained Efficacy
The investigator-reviewed data from the pivotal CK-301-101 trial included 64 patients with laCSCC who received at least one dose of UNLOXCYT (search). The median age of patients was 77 years old with 66% being male, reflecting the population commonly seen in clinical practice. Patients received a median of 29 doses over a median treatment duration of 60 weeks.
The study achieved a 50% objective response rate, including 17 (27%) complete responses and 15 (23%) partial responses. Over a median follow-up of 31 months, responses proved durable with the median duration of response not yet reached.
"These data support clinically meaningful efficacy within this patient population. We observed a high rate of complete responses in patients with laCSCC, which is associated with long-term clinical outcomes," said Dr. Rahul Ladwa, Medical Oncologist at the Princess Alexandra Hospital and Greenslopes Private Hospital and Associate Professor at The University of Queensland, Australia.
Favorable Safety Profile in Elderly Population
The safety profile was comparable to earlier analyses of smaller cohorts. The most common adverse events were anemia and diarrhea, each recorded in 17 (27%) patients. Immune-related adverse reactions (irAEs) were observed in 22 (34%) patients, with Grade ≥3 irAEs occurring in only 1 (2%) patient.
Treatment-emergent adverse events were reported in 61 (95%) patients and considered treatment-related in 50 (78%) patients, with none being fatal. Grade ≥3 treatment-emergent adverse events were reported in 26 (41%) patients and considered treatment-related in 7 (11%).
"Patients with laCSCC are older and have many comorbidities, so we need treatment options that are both efficacious and well tolerated, so patients remain on therapy and experience meaningful benefit," said Dr. Emily Ruiz, Associate Professor of Dermatology at Harvard Medical School and Academic Director of the Micrographic Surgery Center at Brigham and Women's Hospital.
Unique Mechanism of Action
According to Dr. Ruiz, cosibelimab appears to work differently than other checkpoint inhibitors by restoring the adaptive immune response and engaging the innate immune system while preserving the PD-1 (search)/PD-L2 (search) pathway. This unique mechanism may explain the observed clinical results in these patients.
Addressing Significant Medical Need
Cutaneous squamous cell carcinoma (search) is among the most common skin cancers worldwide. While early stages are treatable, an estimated 40,000 US patients each year progress to advanced disease, resulting in nearly 15,000 deaths. Important risk factors include chronic ultraviolet radiation exposure and immunosuppressive conditions.
UNLOXCYT (search) is indicated for the treatment of adults with metastatic cutaneous squamous cell carcinoma (search) or locally advanced CSCC who are not candidates for curative surgery or curative radiation. The recommended dosage is 1,200 mg as an intravenous infusion over 60 minutes every 3 weeks.
"With a median duration of response not yet reached after more than two and a half years of follow-up, UNLOXCYT (search) continues to demonstrate the kind of clinically meaningful efficacy with durable clinical responses and well-tolerated treatment option that patients with laCSCC need," said Dr. Ahmad Naim, Senior Vice President and North America Chief Medical Officer at Sun Pharma.