Key Takeaways:
Inhibrx Biosciences (Nasdaq: INBX) announced its experimental drug INBRX-106 in combination with pembrolizumab achieved a 44% response rate in a Phase 2 cancer trial, more than double the rate of pembrolizumab alone.
"We are greatly encouraged by these early clinical results," Mark Lappe, Chief Executive Officer of Inhibrx, said in a statement.
The interim analysis from the HexAgon study showed 11 of 25 patients on the combination therapy had a confirmed objective response, compared to six of 28 patients on the control arm. The combination arm also produced three complete responses, meaning tumor clearance, while the control arm had none.
Despite the positive data, Inhibrx shares fell 1% to $133 on Monday in a potential 'sell the news' event after the stock surged over 1,000% in the past year. The company plans to start a Phase 3 trial in the third quarter of 2026.
The study evaluated INBRX-106 in patients with treatment-naïve, PD-L1 positive head and neck squamous cell carcinoma. The 22.6% absolute increase in confirmed responses suggests the drug provides a significant benefit over the current standard of care in this population. Pharmacodynamic data supported the clinical findings, showing up to a 15-fold increase in T-cell proliferation for patients receiving the combination treatment.
Inhibrx reported a manageable safety profile, with common low-grade side effects including rash, diarrhea, and fatigue. No treatment-related deaths occurred. The company noted that data on progression-free survival, a key secondary endpoint, are expected in the fourth quarter of 2026.
The results position INBRX-106 as a potentially best-in-class OX40 agonist, but investors appear to have priced in the success during the stock's massive run-up. Traders will now watch for progression-free survival data in Q4 2026 and the initiation of a non-small cell lung cancer study this quarter for the next major catalysts.
This article is for informational purposes only and does not constitute investment advice.
