A phase 2 randomised study of ramucirumab (IMC-1121B) with or without dacarbazine in patients with metastatic melanoma

Background To evaluate the efficacy and safety of ramucirumab (IMC-1121B; LY3009806), a fully human monoclonal antibody targeting the vascular endothelial growth factor receptor-2, alone and in combination with dacarbazine in chemotherapy-naïve patients with metastatic melanoma (MM). Methods Eligible patients received ramucirumab (10 mg/kg) + dacarbazine (1000 mg/m²) (Arm A) or ramucirumab only (10 mg/kg) (Arm B) every 3 weeks. The primary end-point was progression-free survival (PFS); secondary end-points included overall survival (OS), overall response and safety. Findings Of 106 randomised patients, 102 received study treatment (Arm A, N = 52; Arm B, N = 50). Baseline characteristics were similar in both arms. Median PFS was 2.6 months (Arm A) and 1.7 months (Arm B); median 6-month PFS rates were 30.7% and 17.9% and 12-month PFS rates were 23.7% and 15.6%, respectively. In Arm A, 9 (17.3%) patients had partial response (PR) and 19 (36.5%), stable disease (SD); PR and SD in Arm B were 2 (4.0%) and 21 (42.0%), respectively. Median OS was 8.7 months in Arm A and 11.1 months in Arm B. Patients in both arms tolerated the treatment with limited Grade 3/4 toxicities. Interpretation Ramucirumab alone or in combination with dacarbazine was associated with an acceptable safety profile in patients with MM. Although the study was not powered for comparison between treatment arms, PFS appeared greater with combination therapy. Sustained disease control was observed on both study arm.