Dr Migden on RP1 in Advanced Cutaneous Malignancies After Solid Organ Transplant

Michael R. Migden, MD, dermatologist, professor, Department of Dermatology, Division of Internal Medicine and Head and Neck Surgery, Division of Surgery, and program director, ACGME Fellowship:Micrographic Surgery and Dermatologic Oncology, The University of Texas MD Anderson Cancer Center, discusses efficacy data from the phase 1b/2 ARTACUS trial (NCT04349436) evaluating the oncolytic immunotherapy RP1 in patients with advanced non-melanoma cutaneous malignancies who underwent prior solid organ transplant.

Findings presented at the 2024 AACR Annual Meeting showed that evaluable patients administered single-agent RP1 (n = 23) experienced an overall response rate (ORR) of 34.8%, including a complete response rate of 21.7% and a partial response of 13.0%; 4.3% of patients achieved stable disease. The disease control rate was 39.1% with the agent. Moreover, 60.9% of patients experienced progressive disease.

Among the 8 responders, 6 patients had cutaneous squamous cell carcinoma, and 2 patients had Merkel cell carcinoma. At baseline, 6 responders had locally advanced disease, and 2 patients had metastatic disease. 

Regarding safety, the most common any-grade treatment-emergent adverse effects reported in more than 10% of patients (n = 27) included fatigue (33.3%), chills (25.9%), pyrexia (25.9%), anemia (18.5%), increased blood creatinine (18.5%), nausea (18.5%), urinary tract infection (18.5%), decreased appetite (14.8%), and diarrhea (14.8%). Notably, no allograft rejection was reported in any patients.

In a presentation of the data, Migden noted that non-melanoma skin cancer is the most common malignancy in patients who undergo solid organ transplant; however, the optimal treatment of these malignancies within this subgroup of patients has not been well established. Given the lack of treatment options for this population, the efficacy data derived from ARTACUS are encouraging, Migden says. Systemic therapy with immune checkpoint inhibitors is contraindicated for patients who underwent prior solid organ transplant and outcomes for this population have been suboptimal with the use of chemotherapy alone, Migden concludes.