ANS03

ANS03 is a novel, orally bioavailable small molecule tyrosine kinase inhibitor (TKI) developed to target both ROS1 and NTRK kinases. It is classified as a Type II inhibitor, which means it binds to the inactive "DFG-out" conformation of the kinase and extends into an adjacent allosteric pocket. This unique binding mode allows ANS03 to inhibit a broad spectrum of clinically relevant resistance mutations in ROS1 and NTRK fusion-positive cancers—including solvent front mutations (such as ROS1 G2032R, D2033N; NTRK G595R), central beta sheet #6 mutation L2086F in ROS1, and xDFG mutation G667C in NTRK. Preclinical studies have demonstrated potent activity against these alterations with favorable pharmacokinetics and tolerability profiles. ANS03 is being evaluated for use in adult patients with locally advanced or metastatic solid tumors harboring ROS1 or NTRK alterations—including those who have developed resistance to current type I TKIs—and also in pediatric patients aged 12 years or older with similar genetic changes[1][3][4][5][6].