TLDR
- Inhibrx Biosciences stock jumped 17% Monday after positive Phase 2 trial results for head-and-neck cancer drug INBRX-106.
- The drug combined with pembrolizumab achieved a 44% objective response rate vs. 21.4% for pembrolizumab alone.
- 11 of 25 patients in the combination arm responded, versus 6 of 28 in the control arm; three complete responses were recorded in the combination group, none in the control.
- T-cell proliferation in combination-treated patients was up to 15x higher than in those on pembrolizumab alone.
- Phase 3 of the trial is set to begin in Q3 2026, with progression-free survival data expected in Q4 2026.
Inhibrx Biosciences (INBX) stock rose 17% on Monday after the company released positive preliminary data from its Phase 2 HexAgon study for INBRX-106, a drug being tested for head and neck cancer.
Inhibrx Biosciences, Inc., INBX
The stock was already up more than 1,000% over the past 12 months, driven by earlier positive results from another cancer drug, INBRX-109, back in October.
The trial tested INBRX-106 — a hexavalent OX40 agonist — in combination with pembrolizumab against pembrolizumab alone. Patients were first-line, treatment-naïve, and PD-L1 positive with metastatic or unresectable recurrent head and neck squamous cell carcinoma.
The combination arm hit a 44% confirmed objective response rate. The control arm, using pembrolizumab alone, came in at 21.4% — a 22.6 percentage point difference.
The study enrolled 68 patients total, with 33 in the combination arm and 35 in the control arm. The evaluable population was 53 patients.
In that group, 11 of 25 patients on the combination responded. Six of 28 responded on pembrolizumab alone.
Three complete responses were seen in the INBRX-106 combination arm. There were none in the control arm.
T-Cell Data Adds Weight to Results
Beyond response rates, the immune data stood out. Patients on the combination showed up to a 15-fold mean increase in CD8+ and CD4+ T-cell proliferation. Those on pembrolizumab alone saw increases of up to 2.5-fold.
Inhibrx said this provides mechanistic support for the clinical results — in other words, the biology lines up with what they’re seeing in patients.
CEO Mark Lappe said the company was “greatly encouraged by these early clinical results,” pointing specifically to the quality and depth of responses already being observed.
Safety Profile Called Manageable
The combination showed a safety profile the company described as manageable and consistent with what’s expected from an immunotherapy pairing.
The most common treatment-related side effects were rash, diarrhea, fatigue, and infusion-related reactions. Most were low-grade.
No treatment-related deaths were reported in either arm of the trial.
Inhibrx said progression-free survival data from the Phase 2 portion is expected in Q4 2026.
The Phase 3 portion of the HexAgon trial is set to begin in Q3 2026.
🚨 Our MAY Stock Picks Are Live!
A new month means new opportunities. Our analysts have just released their top stock picks for May, highlighting companies with strong momentum that rank highly on our KO Score algorithm. We’re also now sharing trade ideas for both long-term and short-term investors, giving you more ways to spot potential opportunities in the market.
Sign up to Knockout Stocks today and get 50% off to unlock the full list and see which stocks made the cut.
Use coupon code Special50 for your exclusive discount!
Get 3 Free Stock Ebooks
Discover top-performing stocks in AI, Crypto, and Technology with expert analysis.
- Top 10 AI Stocks - Leading AI companies
- Top 10 Crypto Stocks - Blockchain leaders
- Top 10 Tech Stocks - Tech giants
