Primary analysis of a phase 1b multicenter trial to evaluate safety and efficacy of talimogene laherparepvec (T-VEC) and ipilimumab (ipi) in previously untreated, unresected stage IIIB-IV melanoma.

9029^ Background: T-VEC, an HSV-1 derived oncolytic immunotherapy designed to induce systemic antitumor immunity, showed a ≥ 6 mos higher durable response rate vs GM-CSF in a phase 3 melanoma trial (Andtbacka et al. ASCO 2013). This phase 1b/2 study will determine the safety and efficacy of T-VEC as a priming regimen when added to ipi. Methods: Phase 1b studied the safety of T-VEC+ipi. Objective response rate (ORR) was also evaluated with tumor assessments q12w. Blood was collected pre- and post-treatment (tx) for correlative studies. Key criteria: unresected Stage IIIB-IV melanoma, no prior systemic tx, measurable disease, and ≥1 injectable cutaneous, subcutaneous or nodal lesion. T-VEC was given intralesionally at ≤ 4 mL of 106 PFU/mL at wk 1, then 108 PFU/mL at wk 4 and then q2w. Ipi 3 mg/kg q3w was given as 4 infusions starting wk 6. Tx continued until DLT, intolerance, all injectable tumors disappeared, or disease progression (PD) per Immune Related Response Criteria. DLT was any grade (gr) ≥ 4 adver...