Optim: A Randomized Phase Iii Trial To Evaluate The Efficacy And Safety Of Talimogene Laherparepvec (T-Vec) Compared With Subcutaneously (Sc) Administered Gm-Csf For The Treatment (Tx) Of Unresectable Stage Iiib, Iiic, And Iv Melanoma.

TPS8604 Background: T-VEC (formerly OncoVEXGM-CSF) is an oncolytic HSV1 that selectively replicates in tumors. The proposed MOA includes lytic destruction of injected tumors and induction of a systemic anti-tumor immune response enhanced by local GM-CSF expression. Intratumoral T-VEC tx in a 50-patient (pt) ph II study in advanced melanoma (Stage IIIc-IVM1c) was well tolerated and achieved a high rate and duration of response, including 20% CR (Senzer et al., JCO 2009; 27: 5763-71). As immune effects may be delayed, progressive disease (PD) often occurred before response. Based on the ph II data, a randomized ph III trial of T-VEC in unresectable melanoma (the OPTiM study; clinical trials registry NCT00769704) was designed taking into account the response patterns seen with T-VEC and other immunotherapeutic agents. T-VEC is the first armed oncolytic agent to enter pivotal testing worldwide. Methods: OPTiM compares the efficacy and safety of intratumoral T-VEC to sc GM-CSF in 430 pts with treated or untr...