Abstract
TPS5606
Background: Ofranergene obadenovec (Ofra-vec, VB-111) is an anti-cancer gene based immune activator and targeted vascular disruptor. The dual mechanism of action triggers a broad antiangiogenic effect and induces of a tumor directed immune response. A phase II trial in patients with platinum resistant ovarian cancer (PROC) demonstrated that ofra-vec in combination with weekly paclitaxel was well tolerated and associated with a CA-125 Objective Response Rate (ORR) of 58%, a trend for improved survival and induction of an immunotherapeutic effect of tumor infiltration with CD-8 T cells. Based on these observations, a pivotal phase III study was initiated in collaboration with the GOG Foundation, Inc. Methods: Study NCT03398655 is an international, randomized, double-blind, placebo-controlled, phase III study. Eligible patients have recurrent PROC and may have been previously treated with up to 5 prior lines of therapy (but not >2 for PROC). Patient are randomized 1:1 to receive ofra-vec (1x10
13
Viral Particles) with weekly paclitaxel (80mg/m
2
), or weekly paclitaxel with placebo. Randomization is stratified by number of prior treatment lines, prior antiangiogenic therapy and platinum refractory disease status. The dual primary endpoints are OS and PFS. A pre-planned interim analysis of CA-125 response (GCIG) performed by the DSMC met the pre-defined criteria showing that CA-125 ORR in the treatment arm was at least 10% higher than in the control arm. Study is enrolling in the US, EU, Japan and Israel, with 90% enrollment to date. Completion of accrual is anticipated in Q1 2022. Clinical trial information: NCT03398655.