Finasteride and Cutibacterium

NCT07731802 | Not Yet Recruiting Phase 4 FDA Drug

• 1 other identifier: STUDY00025632
• Study Type: interventional
• Target: 40
• Locations: 0 countries
• Sites: N/A

Brief Summary

High levels of Testosterone causes high amounts of skin bacteria (Cutibacterium Acnes) which can go into the skin during a shoulder replacement surgery and cause a terrible infection. The goal of this experiment is to have participants take Finasteride, a medication that blocks testosterone production, for 2 weeks and evaluate the following:

• Blood levels of testosterone
• Amount of bacteria on the skin. Participants will:
• Be assigned to take Finasteride, or a placebo (a look-alike pill with no active medicine) once daily, for 2 weeks
• Have a small sample of their blood collected and their skin swabbed with a Q-tip to determine Testosterone levels and bacteria on the skin
• Blood draw and skin testing will take place before starting Finasteride or the placebo (day 0) and at the end of the experiment (day 14).

Conditions

Dihydrotestosterone; Periprosthetic Joint Infection (PJI); Cutibacterium Acnes

Keywords

placebo; blood draw; skin culture

Outcome Measures

Primary Outcomes (2)

• Cutibacterium skin load

  Skin load will be determined using bacterial culture of the skin and assigning a value based on the report from the microbiology lab: 0 for "no growth"; 0.1 for "growth of 1 colony only" or for "growth in broth only"; and 1, 2, 3 and 4 for 1+, 2+, 3+ and 4+ growth, respectively. Mann-Whitney U test will be used to compare the change in the semi-quantitative skin load at baseline and day 14 in the intervention and control group, along with comparison of the percentage of subjects in each group that began with a high baseline skin load (\>2) and ended with a low skin load (≤1).

  Skin load will be assessed at day 0 and at the end of the study on day 14 of treatment or placebo.

• Serum Dihydrotestosterone (DHT) Level

  Participants blood will be collected and processed for serum DHT level by the certified and state-licensed phlebotomists and clinical laboratory technicians at our intuition, which is in the same building as the outpatient clinic.

  levels will be assessed at baseline and after 14 consecutive days of treatment or placebo.

Study Arms (2)

Finasteride group

EXPERIMENTAL

Drug: Finasteride 1 mg

Placebo group

PLACEBO COMPARATOR

Drug: Placebo Control

Interventions

Finasteride 1 mg DRUG

Patients randomized to the experimental group will receive oral Finasteride 1 mg, taken daily, for two weeks

Finasteride group

Placebo Control DRUG

Patients randomized to the placebo group will receive one pill containing no active medicine, taken daily, for two weeks.

Placebo group

Eligibility Criteria

• Age: 18 Years - 65 Years
• Gender Eligibility Details: We have decided to only include patients of cisgender male participants because these patients have been shown to harbor significantly more Cutibacterium in their skin than females and are at highest risk of shoulder PJI. Because cisgender female patients have been shown to have only small amounts of Cutibacterium in their skin, they were not included as it would be difficult demonstrate a reduction in their Cutibacterium load with any intervention.
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

Inclusion We will include the group most impacted by PJI * Adult males * Age between 18 and 65 Exclusion * History of cryptorchidism, hypospadias, or other congenital abnormality of male reproductive tract * Female sex * Age younger than 18 or older than 65 * Current use of Finasteride or other 5-alpha reductase inhibitors * Current use of hormone replacement medications such as testosterone * Recent antibiotic use within 3 months * Have had a negative reaction to oral Finasteride before * Recent use of acne treatment within 3 months * Self-report very sensitive skin * Allergic to chlorhexidine or isopropyl alcohol * Have open wounds on both shoulders

Contact the study team to discuss eligibility requirements. They can help determine if this study is right for you.

Sponsors & Collaborators

• University of Washington: lead

MeSH Terms

Interventions

Finasteride

Intervention Hierarchy (Ancestors)

Androstenes; Androstanes; Steroids; Fused-Ring Compounds; Polycyclic Compounds; Azasteroids; Steroids, Heterocyclic

Study Officials

• Corey Schiffman, MD

  University of Washington

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Anastasia Whitson

CONTACT

206-755-7847; whitsa@uw.edu

Study Design

• Study Type: interventional
• Phase: phase 4
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, CARE PROVIDER
• Purpose: PREVENTION
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Assistant Professor: School of Medicine, Orthopaedics and Sports Medicine

Study Record Dates

• First Submitted: July 23, 2026
• First Posted: July 28, 2026
• Study Start (Estimated): August 31, 2026
• Primary Completion (Estimated): March 31, 2027
• Study Completion (Estimated): August 31, 2027
• Last Updated: July 28, 2026

Record last verified: 2026-07