Background: In phase III trials, ipilimumab plus nivolumab combination therapy is highly efficacious for advanced melanoma, despite many treatment-related grade 3-4 adverse events (AEs). Here, we... Show moreBackground: In phase III trials, ipilimumab plus nivolumab combination therapy is highly efficacious for advanced melanoma, despite many treatment-related grade 3-4 adverse events (AEs). Here, we report real-world safety and survival outcomes of ipilimumab plus nivolumab for advanced melanoma.Methods: Patients with advanced melanoma who received first-line ipilimumab plus nivolumab between 1-1-2015 and 30-6-2021 were selected from the Dutch Melanoma Treatment Registry. We evaluated response status at 3, 6, 12,18, and 24 months. OS and PFS were estimated with the Kaplan-Meier method. Separate analyses were performed for patients with or without brain metastases and for patients who met the inclusion criteria of the Checkmate-067 trial.Results: In total, 709 patients received first-line ipilimumab plus nivolumab. Three hundred sixty (50.7%) patients experienced grade 3-4 AEs with 211 of them (58.6%) patients requiring hospital admission. Median treatment duration was 42 days (IQR = 31-139). At 24-months, disease control was achieved in 37% of patients. Median PFS since the start of treatment was 6.6 months (95%CI: 5.3-8.7), and median OS was 28.7 months (95%CI: 20.7-42.2). CheckMate-067 trial-like patients had a 4-year OS of 50% (95%CI: 43-59). Among patients with no, asymptomatic or symptomatic brain metastases, the 4-year OS probabilities were 48% (95%CI: 41-55), 45% (95%CI: 35-57), and 36% (95%CI: 27-48).Conclusion: Ipilimumab plus nivolumab can achieve long-term survival in advanced melanoma patients in a real-world setting, including patients not represented in the CheckMate-067 trial. However, the proportion of patients with disease control in the real-world is lower compared to clinical trials. Show less