Preclinical studies have shown that androgen receptor-mediated CDK4/6 activation potentiates cell proliferation and endocrine therapy resistance in prostate cancer models, and CDK4/6 inhibition leads to tumor growth inhibition. The CDK4/6 inhibitor abemaciclib has been shown to significantly increase endocrine therapy efficacy in metastatic breast cancer, suggesting its potential as a treatment for patients with metastatic castration-resistant prostate cancer (mCRPC). In the phase II CYCLONE 1 study, Agarwal and colleagues evaluate the clinical activity of abemaciclib in heavily pretreated patients with refractory mCRPC. The authors report an objective response rate of 6.8% and a disease control rate of 45.5%, with a median time to PSA progression of 6.5 months, a 2.7-month median radiographic progression-free survival (rPFS), a 6-month rPFS rate of 24.9%, and an 8.4-month overall survival. Abemaciclib was well tolerated, with no treatment-related grade 4 or 5 adverse events. Overall, abemaciclib showed initial clinical activity in this heavily pretreated patient...

You do not currently have access to this content.