Therapy With Metronomic Cyclophosphamide (mCyc) for Previously-Treated Metastatic Castrate-Resistant Prostate Cancer (mCRPC).

Introduction: Despite the introduction of various novel therapies for management of metastatic castrate resistant prostate cancer (mCRPC) in recent decades, available treatment options are finite and remain limited. Multiple historical studies have demonstrated activity and a favorable toxicity profile of oral metronomic cyclophosphamide (mCyc) in prostate cancer (PCa). Unlike the cytotoxic immunosuppressive effects of high-dose intravenously-administered cyclophosphamide, continuous low doses of oral mCyc have a unique immune-stimulatory mechanism of action.