Immunotherapy-Treated Melanoma Brain Metastases Within The French National Cohort. Melbase.

9556 Background: Melanoma brain metastases (BM) are associated with poor prognosis. Although novel therapies such as ipilimumab (IPI) and anti-PD1 (aPD1: nivolumab and pembrolizumab) have shown their efficacy in BM, little information is available in their use in BM. We report the efficacy of immunotherapy treatment on melanoma BM in “real-life” condition within MelBase. Methods: MelBase is a French multicentric clinical and biological cohort dedicated to the prospective follow-up (FU) of adults with unresectable stage III or stage IV melanoma. Since March 2013, 754 patients were included (25 centers). Available data were collected (11/21/15) and analyzed (demography, overall survival (OS), progression-free survival (PFS), response rate). Results: 2 subgroups are presented: BM treated with IPI (sgI) and BM treated with aPD1 (sgaPD1).The characteristics at the initiation of the treatment are: SgI (n = 39): mean age was 61 years, 82% were PS 0-1, 32% had elevated LDH, 67% non-mutated BRAF. Median FU was 11.2 months. OS was 6.6 months (IC95 :4.7−12.5), PFS 2.4 months (IC95 :1.8−3.4). 29 patients were evaluated: 7% complete response (CR), 3% partial response (PR), 17% stable disease (SD) and 72% progressive disease (PD). The best overall response (BORR) was 8% and disease control rate (DCR) was 21%. In sgaPD1 (n = 39): mean age was 56 years, 79% were PS 0-1, 45% had elevated LDH, 49% non-mutated BRAF. Median FU was 5.6 months, OS 5.5 months (IC95 :3.7-not reached), PFS 2.8 months (IC95:2.4-not reached). 30 patients were evaluated: 3% CR, 13% PR, 18% SD and 44% PD. BORR was 15% and DCR 33%. Conclusions: IPI results are consistent with data published by Margolin (2014) and Queirelo (2015) with DCR ranging from 24 to 27% and median survival from 4.3 to 7.0 months. Concerning anti-PD1, our results are also consistent with DCR observed in Harriet (2015) study on 18 patients. We show the first survival data obtained in patients with BMs treated by anti-PD1. Although direct comparison is difficult outside a controlled study and aPD1 data need to mature, IPI and aPD1 show comparable efficacy in melanoma BM lower than efficacy with BRAF inhibitors.