Inhibrx reports 44% response rate when paired with Keytruda in head-and-neck cancer Phase 2 trial

Inhibrx Biosciences said its experimental agent INBRX-106 boosted the activity of Merck's Keytruda in a Phase 2 study of a head-and-neck cancer. The combination achieved a 44% overall response rate, compared with 21.4% for Keytruda alone, and produced three complete responses, whereas the control arm saw none.

The data suggest that stimulating the OX40 T‑cell receptor, the mechanism of INBRX-106, may provide the first add‑on effect that differentiates from Keytruda monotherapy, according to Stifel analyst Dara Azar. The results were described as a differentiated approach to cancer immunotherapy.

The positive readout comes amid speculation of a possible Merck‑led buyout of Inhibrx, which has driven the company's market value to nearly $2 billion.