Real-world use, safety, and survival of ipilimumab in metastatic cutaneous melanoma in The Netherlands

Phase III trials with ipilimumab showed an improved survival in patients with metastatic melanoma. We evaluated the use and safety of ipilimumab, and the survival of all patients with metastatic cutaneous melanoma (N=807) receiving ipilimumab in real-world clinical practice in The Netherlands using data from the Dutch Melanoma Treatment Registry. Patients who were registered between July 2012 and July 2015 were included and analyzed according to their treatment status: treatment-naive (N=344) versus previously-treated (N=463). Overall, 70% of treatment-naive patients and 62% of previously-treated patients received all four planned doses of ipilimumab. Grade 3 and 4 immune-related adverse events occurred in 29% of treatment-naive patients and 21% of previously-treated patients. No treatment-related deaths occurred. Median time to first event was 5.4 months [95% confidence interval (CI): 4.7-6.5 months] in treatment-naive patients and 4.4 months (95% CI: 4.0-4.7 months) in previously-treated patients. Median overall survival was 14.3 months (95% CI: 11.6-16.7 months) in treatment-naive patients and 8.7 months (95% CI: 7.6-9.6 months) in previously-treated patients. In both patient groups, an elevated lactate dehydrogenase level (hazard ratio: 2.25 and 1.70 in treatment-naive and previously-treated patients, respectively) and American Joint Committee on Cancer M1c-stage disease (hazard ratio: 1.81 and 1.83, respectively) were negatively associated with overall survival. These real-world outcomes of ipilimumab slightly differed from outcomes in phase III trials. Although phase III trials are crucial for establishing efficacy, real-world data are of great added value enhancing the generalizability of outcomes of ipilimumab in clinical practice.