9081 Background: Brain is a common site for melanoma metastases. Responses to dabrafenib have already been reported in over 50% of patients. We aimed at assessing response rate (RR) to vemurafenib (Vem). Methods: Patients with BRAF positive melanoma and asymptomatic brain metastases at initiation of Vem were eligible. Records were analysed retrospectively to calculate RR (at least 30% decrease in the sum of diameters of target lesions), duration of response and time to CNS progression (TTP). Results: 18 patients with CNS metastasis received Vem (M/F=8/10; median age 50); 9 received no prior therapy to the brain (group A), 6 had previous surgery and/or radiotherapy with residual disease (group B; n=6), 3 patients had prior "brain therapy" but with evidence of progression in CNS before the start of Vem and were added to group A (n=9+3=12). 50% RR was observed in group A; 5 had no prior therapy, 1 relapsed after resection/WBRT. Duration of response was: 8, 8, 8, 16, 32 weeks and 1 not reached yet. Similarly, 50% RR was observed in group B; however contribution of Vem to CNS control in this group was more difficult to assess. Duration of responses: 4, 26, 33 weeks. All except 2 patients progressed in CNS before, or at the time of, systemic progression. Median TTP in group A was: 21 weeks (16-41) in responding patients and 12 weeks (4-22) in those without a response (includes SD). Median TTP in group B = 44 weeks (16-60) in responders, 8 weeks (3-16) in non-responders. Conclusions: Vemurafenib resulted in 50% CNS response rate. Prospective comparison to dabrafenib may be warranted.