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Pre-randomization Dutasteride

Siami, Paul F., M.D. · FDA-approved active Small molecule

Dutasteride inhibits both type 1 and type 2 5-alpha reductase enzymes, blocking the conversion of testosterone to dihydrotestosterone (DHT).

Dutasteride inhibits both type 1 and type 2 5-alpha reductase enzymes, blocking the conversion of testosterone to dihydrotestosterone (DHT). Used for Benign prostatic hyperplasia (BPH) with lower urinary tract symptoms, Male pattern hair loss (androgenetic alopecia).

At a glance

Generic namePre-randomization Dutasteride
SponsorSiami, Paul F., M.D.
Drug class5-alpha reductase inhibitor
Target5-alpha reductase (type 1 and type 2)
ModalitySmall molecule
Therapeutic areaUrology
PhaseFDA-approved

Mechanism of action

By inhibiting 5-alpha reductase, dutasteride reduces DHT levels in the prostate and serum. This leads to shrinkage of the prostate gland and improved urinary flow in men with benign prostatic hyperplasia. The dual inhibition of both isoforms makes it more potent than finasteride, which only inhibits type 2 reductase.

Approved indications

Common side effects

Key clinical trials

Primary sources

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SourceUsed for
ClinicalTrials.govTrial enrolment, design, endpoints, results