Nivolumab Prior to Surgery in Patients With Merkel Cell Carcinoma
Posted: Monday, May 18, 2020
In reportedly the first trial of anti–PD-1 therapy in the neoadjuvant setting for resectable Merkel cell carcinoma, treatment with nivolumab prior to surgical resection induced major pathologic and radiographic responses in approximately half of patients. These early markers of response significantly predicted improved recurrence-free survival, according to the results of the CheckMate 358 trial published in the Journal of Clinical Oncology.
“This treatment regimen seemed to be generally tolerable and should be further explored as a potentially beneficial adjunct to surgery in patients with Merkel cell carcinoma,” stated Paul Nghiem, MD, PhD, of the University of Washington, Seattle, and colleagues.
In this phase I/II study, 39 patients with stage IIA to IV resectable Merkel cell carcinoma received nivolumab at 240 mg intravenously on days 1 and 15, with surgery following on day 29. Tumor progression (n = 1) or adverse events (n = 2) prevented surgery in three patients.
Among the 36 patients who underwent surgery, 17 (47.2%) achieved a pathologic complete response and 18 (54.5%) had a radiographic response—a tumor reduction of at least 30%. Responses were observed regardless of tumor Merkel cell polyomavirus, PD-L1, or tumor mutational burden status. At a median follow-up of 20.3 months, median recurrence-free survival and overall survival were not reached, and no patient with a pathologic complete response had tumor relapse during observation.
As for safety, any-grade treatment-related adverse events were reported in 18 patients (46.2%) and grade 3 or 4 events were observed in 3 patients (7.7%). The most common any-grade treatment-related adverse events observed with neoadjuvant nivolumab were skin reactions (10.3%). “Additional investigation of these promising findings is warranted,” concluded the authors.
Disclosure: For full disclosures of the study authors, visit ascopubs.org.
