Inhibrx's INBRX-106 Nearly Doubles Response Rate and Achieves Interim Median PFS of 9.6 months in Phase 2 HNSCC Study
First OX40 agonist to demonstrate clinical benefit in a randomized study INBRX-106 plus pembrolizumab delivers a 48.3% cORR and 72.4% of patients remain progression free at 6 months, compared with 26.5% and 42.8% for pembrolizumab alone Results are most pronounced in HPV+ patients, with cORR (80.0% vs 33.3%), CR rate (30.0% vs 0%), and PFS6 improvement (90.0% vs 33.0%) vs pembrolizumab alone Inhibrx will expand the Phase 2 study by approximately 50 HPV+ patients and may serve as a potential pathway to accelerated approval Positive results support large expansion opportunities into highly immunogenic tumors and combination with cancer vaccines SAN DIEGO, Sept. 8, 2026 /PRNewswire/ -- Inhibrx Biosciences, Inc. (Nasdaq: INBX) ("Inhibrx" or the "Company"), a clinical-stage biopharmaceutical company focused on developing a broad pipeline of novel biologic therapeutic candidates, today announced the primary endpoint results from the randomized and controlled Phase 2 portion of the HexAgon study, which is evaluating the safety and efficacy of INBRX-106, a hexavalent OX40 agonist, in combination with pembrolizumab (the combination arm) versus pembrolizumab monotherapy (the control arm) in first-line patients with treatment-naïve, PD-L1 positive (CPS ≥ 20) metastatic or unresectable recurrent head and neck squamous cell carcinoma (HNSCC).