Abstract 5324
Background
IMO-2125 (tilsotolimod) is a TLR9 agonist with potent immunostimulating activity. An ongoing Phase 1/2 clinical study of intratumoral tilsotolimod + ipi (NCT02644967) shows the combination to be well-tolerated over the range of tilsotolimod doses tested, with evidence of dendritic cell activation and infiltration of tumorspecific immune cells in subject samples. Clinical responses (including durable CR > 21 months) have been seen in anti-PD-1-refractory subjects. Because no therapy has been shown to prolong survival after failure of first-line anti-PD-1 immunotherapy, this study is designed to show superiority of tilsotolimod + ipi over ipi alone.
Trial design
This is a randomized phase 3 global, multi-center, open-label comparison of ipi (3 mg/kg) +/- intratumoral tilsotolimod (8mg) in subjects with advanced cutaneous or mucosal melanoma with disease progression while on anti-PD-1 therapy. Eligible subjects are age ≥18 years with histologically confirmed Stage III or IV melanoma, ≥1 measurable lesion accessible for injection, ECOG ≤1, adequate organ function, and excluding those with previous TLR agonist treatment, prior ipi (except adjuvant), or CNS disease other than stable (≥4 wks) brain mets. Subjects will be randomized 1:1 to either ipi alone (Arm A) or tilsotolimod + ipi (Arm B) and stratified on the duration of prior antiPD-1 therapy (≥12 weeks/<12 weeks), stage (M1c/other), BRAF status and prior targeted therapy (TT) (BRAF wt/BRAF mut+ with TT/BRAF mut+ no TT). Primary endpoints comprise RECIST v1.1 ORR by independent central review and OS. Secondary endpoints include DRR, TTR, PFS, PRO, and safety. Treatment duration is 10 weeks (4 ipi doses) for subjects in Arm A and 24 weeks (9 tilsotolimod + 4 ipi doses) in Arm B. Final analysis (ORR and OS) will occur when 219 death events have occurred, estimated at 36 months after the first randomization. After 110 deaths, an interim analysis will be done for OS. Enrollment is planned as 308 subjects at around 80 centers in 10 countries. It is currently recruiting in the US and Australia with study initiation ongoing in EU and Canada.
Clinical trial identification
NCT03445533.
Legal entity responsible for the study
Idera Pharmaceuticals, Inc.
Funding
Idera Pharmaceuticals, Inc.
Editorial Acknowledgement
Disclosure
J. Geib, S. Rahimian, S. Swann: Employee: Idera Pharmaceuticals. A. Diab: Advisory board: Idera Pharmaceuticals. All other authors have declared no conflicts of interest.