Overview of Pivotal Studies for Prostate Cancer Risk Reduction, Past and Present

Dihydrotestosterone (DHT) reduction by dutasteride vs finasteride, baseline to end of active treatment. At therapeutic dose, from baseline to end of active treatment (24 weeks), dutasteride reduced DHT by >90%, significantly greater reduction than the 70.8% suppression observed with finasteride and with less variability. Data from Clark et al.¹⁹

Pivotal studies with 5α-reductase inhibitors (5-ARIs), natural supplements, and combination therapies for prostate cancer. Prostate Cancer Prevention Trial (PCPT), finasteride for PCa prevention in healthy men; Selenium and Vitamin E Cancer Prevention Trial (SELECT) in men at low risk of prostate cancer; Reduction by Dutasteride of Prostate Cancer Events (REDUCE) trial, Phase III prostate cancer prevention trial; Reduction by Dutasteride of Clinical Progression Events in Expectant Management (REDEEM) trial, disease progression and interval to initiation of more aggressive cancer with dutasteride in men with localized prostate cancer; and Therapeutic Assessment of Rising PSAs (TARP), effect of combination dutasteride and bicalutamide therapy on extending interval to disease progression therapy in men with asymptomatic recurrent prostate cancer after first-line androgen deprivation. Data from GlaxoSmithKline.⁴⁵