TQB3126

TQB3126 is an investigational, orally bioavailable small molecule inhibitor that selectively targets the alpha isoform of phosphoinositide 3-kinase (PI3Kα). Developed by Chia Tai Tianqing Pharmaceutical Group, TQB3126 is designed to inhibit the PI3K/AKT/mTOR signaling pathway, which is frequently hyperactivated in various malignancies, most notably in breast cancers harboring mutations in the PIK3CA gene. By binding to the p110α catalytic subunit, TQB3126 prevents the phosphorylation of phosphatidylinositol 4,5-bisphosphate (PIP2) into phosphatidylinositol 3,4,5-trisphosphate (PIP3), thereby blocking downstream signaling that drives tumor cell proliferation, survival, and metabolism. The drug is currently being evaluated in Phase I/II clinical trials for the treatment of advanced breast cancer, both as a monotherapy and in combination with other standard-of-care therapies.