USRF Research

PCPT Facts at-a-Glance

Primary Hypothesis:

Finasteride can reduce the prevalence of prostate cancer in healthy adult men

Primary Endpoint:

Diagnosis of prostate cancer during 7-year study period or at end-of-study biopsy.


National Cancer Institute (finasteride donated by Merck & Co.)


Southwest Oncology Group

Principle Investigator:

Ian Thompson, M.D.

Study sites:

221 across U.S.


$73 million


Men > 55 years of age with a normal digital rectal exam, IPSS < 20, and serum PSA < 3.0 ng/ml.

Number of Men :



        Enrolled: 24,482


        Randomized: 18,882


        In Final Analysis: 9,060 (excluded were men who were lost to follow-up (7-8%), died during study (6-7%), terminated early (13-14%), or refused end-of-study biopsy (20-25%).

Racial breakdown:

White 92%, Black 3.8%, Hispanic 2.8%, Other 1.4%


Randomized (1:1), placebo-controlled trial, double-blind (after 3 month single blind placebo lead-in), planned 7-year study period


Jan, 1994 (1st man randomized) to Feb 21. 2003, when study terminated 15 months before anticipated conclusion (86.3% of men completed 7 years of study)

Overall Detection of Prostate Cancer:



803/4368 men in finasteride group (18.4%)


1147/4692 men in placebo group (24.4%)


24.8% risk reduction over 7 years (P<0.001)

Occurrence of High-Grade Prostate Cancer (Gleason Score > 7) :



280/757 tumors in finasteride group (37.0%), or 6.4% of entire group


237/1068 tumors in placebo group (22.2%), or 5.1% of entire group