Inhibrx Biosciences Advances Two Oncology Programs with Key Enrollment Milestones and Upcoming Data Readouts
Key Insights
Inhibrx has recruited 46 of 60 patients in its Phase 2/3 trial evaluating INBRX-106 plus Keytruda versus Keytruda alone for first-line treatment of head and neck squamous cell carcinoma, with enrollment completion expected in Q1 2026.
The company completed enrollment of 34 patients in November 2025 for its Phase 1/2 trial of INBRX-106 plus Keytruda in checkpoint inhibitor refractory or relapsed non-small cell lung cancer.
Ozekibart expansion cohorts show progress with 44 patients enrolled in colorectal cancer combination therapy, demonstrating well-tolerated treatment with durable responses and high disease control rates.
Inhibrx Biosciences announced significant enrollment progress across its oncology pipeline, with two key programs advancing toward critical data readouts in 2026. The clinical-stage biopharmaceutical company provided updates on INBRX-106 combination trials and ozekibart expansion cohorts, marking important milestones in its precision-engineered therapeutic development strategy.
INBRX-106 Program Advances in Head and Neck and Lung Cancers
The company has recruited 46 of the targeted 60 patients in the randomized Phase 2 portion of its Phase 2/3 clinical trial evaluating INBRX-106 in combination with Keytruda versus Keytruda monotherapy as first-line treatment for patients with unresectable or metastatic head and neck squamous cell carcinoma (HNSCC). Inhibrx expects to complete enrollment in the Phase 2 portion during the first quarter of 2026.
The trial specifically recruits patients who have not received prior systemic therapy for unresectable or metastatic HNSCC and have tumor PD-L1 (search) CPS expression equal to or greater than 20. Patients are randomized one-to-one to receive either INBRX-106 in combination with Keytruda or Keytruda alone. The primary endpoint of the Phase 2 portion is overall response rate, supported by secondary endpoints including duration of response, progression-free survival, and safety.
In a parallel development, Inhibrx completed enrollment in November 2025 of its Phase 1/2 trial evaluating 34 patients with checkpoint inhibitor refractory or relapsed non-small cell lung cancer (NSCLC) in combination with Keytruda. Primary endpoints for this cohort include objective response rate, disease control rate, duration of response, and safety.
The company acknowledged that current datasets for both HNSCC and NSCLC lack sufficient maturity to support interpretation and conclusions on program viability. Inhibrx expects that data should be mature enough in the second half of 2026 to determine whether INBRX-106 in combination with Keytruda demonstrates superior efficacy and sustained clinical benefit relative to current standard of care.
Ozekibart Shows Promise in Colorectal Cancer and Ewing Sarcoma
Inhibrx completed enrollment of 44 patients in late October 2025 in the expansion cohort of its Phase 1/2 trial evaluating ozekibart in combination with FOLFIRI (search) in heavily pretreated (third and fourth line) advanced or metastatic, unresectable colorectal cancer. The company reported that ozekibart in combination with FOLFIRI was well tolerated, with durable responses and a high rate of disease control. Progression-free survival data should mature in the second quarter of 2026.
The company also expects to complete enrollment in its Phase 1/2 trial of ozekibart in combination with irinotecan and temozolomide for advanced or metastatic, unresectable, relapsed, or refractory Ewing sarcoma in the second quarter of 2026. If current response and duration trends continue, Inhibrx plans to meet with the FDA in the second half of 2026 to discuss an accelerated approval pathway for this indication.
Therapeutic Mechanisms and Development Strategy
INBRX-106 is a precisely engineered hexavalent sdAb-based therapeutic candidate targeting OX40 (search), designed as an optimized agonist of this co-stimulatory receptor. It is currently being investigated in combination with Keytruda in patients with locally advanced or metastatic solid tumors, specifically HNSCC and NSCLC.
Ozekibart represents a precision-engineered, tetravalent death receptor 5 (DR5 (search)) agonist antibody designed to exploit tumor-biased cell death induced by DR5 activation. Inhibrx previously read out a successful single agent registration study in chondrosarcoma, with a BLA filing expected in early Q2 of 2026.
Both therapeutic candidates utilize multivalent formats where precise valency can be optimized in a target-centric way to mediate appropriate agonist function, reflecting Inhibrx's protein engineering platform approach to addressing complex target and disease biology requirements.