GT Biopharma shares surge 12.26% premarket after FDA clears GTB-5550 IND for Phase 1 trial.

GT Biopharma (NASDAQ: GTBP) surged 12.26% in premarket trading following the announcement of FDA clearance for its Investigational New Drug (IND) application for GTB-5550, a B7-H3-targeted TriKE® NK cell engager. The regulatory milestone enables the company to initiate a Phase 1 dose-escalation trial in mid-2026, testing subcutaneous dosing across seven solid tumor cohorts. The news underscores progress in GT Biopharma’s immuno-oncology pipeline, with the CEO describing the clearance as a “defining moment” for advancing its third TriKE-based therapy into clinical trials. The trial’s focus on aggressive cancers like prostate and pancreatic, combined with the platform’s innovative design, has bolstered investor confidence in the company’s long-term potential.