Inhibrx reports 9.6-month median PFS for OX40 agonist combo in phase 2 head-neck cancer trial

Inhibrx Biosciences presented updated data from its phase‑2 HexAgon study of the hexavalent OX40 agonist INBRX‑106 combined with Merck’s Keytruda in patients with untreated metastatic or unresectable recurrent head‑and‑neck squamous cell carcinoma.

The interim analysis showed an objective response rate of 48.3% for the combination versus 26.5% for Keytruda alone, meeting the trial’s primary endpoint.

Median progression‑free survival was 9.6 months with the combo, nearly double the 4.9 months observed with Keytruda monotherapy, and six‑month PFS rates were 72.4% versus 42.8%.

The results, highlighted by the CEO, suggest the OX40 agonist adds durable benefit to checkpoint inhibition in this high‑PD‑L1 population.