A Phase Ii Study Of Talimogene Laherparepvec (T-Vec) And Pembrolizumab In Patients With Metastatic Sarcoma.

11516Background: T-VEC is an oncolytic immunotherapy derived from HSV type-1 that is modified to selectively replicate within tumors and produce GM-CSF. Pembrolizumab (P) demonstrated activity in selective sarcoma (SAR) subtypes. The combination of T-VEC and P has shown favorable safety and efficacy in melanoma. We performed an open-label, single-center, phase II study evaluating T-VEC and P in patients (pts) with advanced SAR who failed at least one standard systemic therapy where available. Methods: Pts received P (200mg/dose) and ≤4ml of T-VEC injected into palpable tumor site(s). Both drugs were administered on day 1 of a 21-day cycle. The primary endpoint was best objective response rate (RR) (complete response and partial response [PR]) at 24 weeks by RECIST 1.1, with 30% as promising and 5% as not promising. If ≥ 3 responses were observed in 20 pts the combination would be claimed to be positive. Secondary endpoints included adverse events (AEs), RR by irRECIST, progression free and overall surviva...