Safety and efficacy of nivolumab in patients with rare melanoma subtypes who progressed on or after ipilimumab treatment: a single-arm, open-label, phase II study (CheckMate 172)

Background: Nivolumab has been widely studied in non-acral cutaneous melanoma; however, limited data are available in other melanoma subtypes. We report outcomes by melanoma subtype in patients who received nivolumab after progression on prior ipilimumab. Patients and methods: CheckMate 172 was a phase II, single-arm, open-label, multicentre study that evaluated nivolumab in patients with advanced melanoma who progressed on or after ipilimumab. Patients received 3 mg/kg of nivolumab, every 2 weeks for up to 2 years. The primary end-point was incidence of grade >= 3, treatment-related select adverse events (AEs). Results: Among 1008 treated patients, we report data on patients with non-acral cutaneous melanoma (n = 723 [71.7%]), ocular melanoma (n = 103 [10.2%]), mucosal melanoma (n = 63 [6.3%]), acral cutaneous melanoma (n = 55 [5.5%]) and other melanoma subtypes (n = 64 [6.3%]). There were no meaningful differences in the incidence of grade >= 3, treatment-related select AEs among melanoma subtypes or compared with the total population. No new safety signals emerged. At a minimum follow-up of 18 months, median overall survival was 25.3 months for non-acral cutaneous melanoma and 25.8 months for acral cutaneous melanoma, with 18-month overall survival rates of 57.5% and 59.0%, respectively. Median overall survival was 12.6 months for ocular melanoma and 11.5 months for mucosal melanoma, with 18-month overall survival rates of 34.8% and 31.5%, respectively. Conclusions: The safety profile of nivolumab after ipilimumab is similar across melanoma subtypes. Compared with non-acral cutaneous melanoma, patients with acral cutaneous melanoma had similar survival outcomes, whereas those with ocular and mucosal melanoma had lower median overall survival. (C) 2019 Elsevier Ltd. All rights reserved.