PTT-4256

PTT-4256 is an oral small molecule from Pathios Therapeutics. An orally bioavailable, selective inhibitor of GPR65, an acid-sensing receptor on immune cells; the company's case is that the acidic tumour environment acts through GPR65 to switch immune cells into a suppressed, pro-tumour state. Its furthest stage is phase 1, for advanced solid tumours. ClinicalTrials.gov registers it in one study linked below. Phase 1/2 RAISIC-1 NCT06634849 recruiting (Australia). Whether it works in people has not been established unless a trial below reports it.