YF550

YF550 is a highly selective and potent small molecule inhibitor of KIF18A (Kinesin Family Member 18A), a mitotic kinesin motor protein, currently in preclinical development by InventisBio for the treatment of chromosomally unstable (CIN+) cancers. KIF18A plays a vital role in chromosome alignment during mitosis; while it is essential for the survival and proliferation of CIN+ cells, it is largely dispensable for near-diploid cells, providing a therapeutic window for selective oncology treatment. Preclinical data indicates that YF550's potency correlates with the aneuploidy score of cancer cells, suggesting its utility as a biomarker for patient selection. The compound has demonstrated superior efficacy and tumor regression in ovarian and HER2-positive breast cancer xenograft models compared to other KIF18A inhibitors, supported by favorable ADME and pharmacokinetic profiles.