BTX-9341

BTX-9341 is a first-in-class, oral, small molecule degrader of cyclin-dependent kinase 4 (CDK4) and cyclin-dependent kinase 6 (CDK6), developed by Biotheryx. It is designed to catalytically degrade CDK4/6 proteins, leading to robust inhibition of Cyclin E and CDK2 transcription, cell cycle arrest at the G0/G1 phase, and ultimately anti-tumor activity. Unlike traditional CDK4/6 inhibitors, BTX-9341 overcomes resistance mechanisms seen in patients previously treated with these inhibitors. Preclinical studies have demonstrated its superior efficacy compared to standard-of-care regimens in both inhibitor-naïve and resistant models of hormone receptor-positive/HER2-negative (HR+/HER2-) breast cancer. The drug also shows synergy with selective estrogen receptor degraders such as fulvestrant when used in combination therapy[1][2][5][7]. BTX-9341 has good oral bioavailability and blood-brain barrier penetration; it has shown activity not only in breast cancer but also in glioblastoma multiforme (GBM) models[6].