EXCLUSIVE: GT Biopharma Announces IND Submission For GTB-5550 TriKE; Reports Preliminary Unaudited Cash Balance Of ~$7M As Of Dec. 31, 2025

GT Biopharma targets a portion of the estimated $362 billion global solid tumor market with its B7-H3 TrikePreliminary, unaudited cash balance of approximately $7 million as of December 31, 2025 anticipated to extend

GT Biopharma targets a portion of the estimated $362 billion global solid tumor market with its B7-H3 Trike

Preliminary, unaudited cash balance of approximately $7 million as of December 31, 2025 anticipated to extend cash runway into Q3 2026

"The IND for GTB-5550 represents the third NK cell engager we plan to move into clinical
development and a tremendous accomplishment for the company", said Michael Breen,
Executive Chairman and Chief Executive Officer of GT Biopharma. "As we continue actively
enrolling the Phase 1 trial with GTB-3650 in myeloid blood cancer, we expect the next data
readout in 1H 2026 could provide potential evidence of clinical activity. Initiation of a Phase 1
basket trial with GTB-5550 for multiple solid tumors is planned for 2026. We look forward to
applying the clinical learnings from the GTB-3650 study to help inform the GTB-5550 program,
which targets a patient population with B7-H3 expressing solid tumors that is orders of
magnitude larger than the myeloid blood cancer patient population." The global market for B7-
H3 expressing solid tumor cancers accounts for a portion of the estimated $362 billion global
solid tumor cancers market (according to Data Bridge Market Research). B7-H3 expressing
solid tumor cancers are estimated to account for a significant portion of solid tumor cancers.