Dr Lee on the Preliminary Safety of Nivolumab for Resectable dMMR Endometrial Cancer

"The most common adverse effects was dermatitis or skin rash, which [was in line with] other immune-oncology trials. Just 2 patients [experienced] grade 3 adverse effects: 1 patient [had] anemia, and 1 patient had skin rash."

Yong Jae Lee, MD, PhD, an associate professor at Yonsei University College of Medicine, discussed the clinical relevance of preliminary safety findings from the phase 2 NIVEC trial (NCT05795244), which evaluated nivolumab (Opdivo) in patients with completely resectable mismatch repair–deficient (dMMR) endometrial cancer.

Findings from the trial presented at the 2025 SGO Annual Meeting on Women’s Cancer demonstrated a clinical complete response (CR) rate of 80% in patients treated with nivolumab (n = 15), suggesting its potential utility as an alternative to surgery for patients who are unable or unwilling to undergo operative management. Among 12 patients to achieve a CR, 7 did not proceed to surgery and remained in follow-up at data cutoff. Notably, all 3 patients who did not experienced a CR had a partial response, including 2 patients with stage IA disease and 1 patient with stage IB disease.

Lee emphasized the favorable safety profile observed in the trial. Adverse effects (AEs) did not lead to treatment discontinuation in any patients. The most common AEs were dermatologic, such as skin rash or dermatitis (any-grade, 30%), and were consistent with other trials of immune checkpoint inhibitors. Two patients experienced grade 3 AEs events—one case of anemia and one case of skin rash. The latter was well controlled using topical corticosteroids or systemic steroid therapy, Lee said. No unexpected immune-related toxicities or treatment-limiting AEs were reported.

Based on these preliminary findings, Lee stated that immune checkpoint inhibition with nivolumab may offer a viable non-surgical therapeutic alternative in patients with resectable dMMR cervical cancer. He underscored the importance of further evaluation to confirm the long-term benefit of this approach, particularly in patients for whom standard surgical intervention is not feasible.