1013P Similar overall survival in tebentafusp-treated 2L+ metastatic uveal melanoma regardless of prior immunotherapy

Abstract

Tebentafusp is a bispecific consisting of an affinity-enhanced T-cell receptor fused to an anti-CD3 effector that can redirect T-cells to target gp100+ cells. In a randomized phase III study of tebentafusp in 1L metastatic uveal melanoma (mUM) [NCT03070392], tebentafusp demonstrated OS benefit vs. investigator’s choice including checkpoint immunotherapy (IO). As checkpoint inhibitors (CPI) may alter the tumor immune profile, we explored the impact of prior IO treatment on clinical outcomes (efficacy and on-target adverse events) and immune phenotype in a phase II study of 2L+ patients with mUM treated with tebentafusp [NCT02570308].