BLU-222 + ribociclib + fulvestrant

This is an investigational **combination therapy** for hormone receptor-positive, HER2-negative (HR+/HER2-) advanced or metastatic breast cancer. It consists of BLU-222, a selective, potent, orally bioavailable cyclin-dependent kinase 2 (CDK2) inhibitor; ribociclib, an approved CDK4/6 inhibitor; and fulvestrant, an estrogen receptor antagonist. BLU-222 is designed to overcome resistance to CDK4/6 inhibitors by inhibiting CDK2-driven cell cycle progression, a mechanism implicated in treatment-resistant tumors. Early-phase clinical studies have shown this combination to be well-tolerated at clinically active doses with no dose-limiting toxicities and with early signs of antitumor activity, including biomarker reductions in thymidine kinase 1 and circulating tumor DNA in patients who progressed on prior CDK4/6 inhibitors[4][6][8]. Ribociclib and fulvestrant together are already established as an effective and standard-of-care combination in this patient population, and the addition of BLU-222 aims to further delay or overcome resistance by targeting a complementary cell cycle pathway[2][5].

Brand names

Kisqali (ribociclib)Faslodex (fulvestrant)

Other names

BLU-222 + ribociclib + fulvestrant