DihydrotestosteronePhase 4NCT07731802
Finasteride and Cutibacterium
A Phase 4 study testing Finasteride 1 mg in people with Dihydrotestosterone and Periprosthetic Joint Infection (PJI), run by University of Washington.
Trial 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. Read more about this study
- Who is it for?
- Ages 18 to 65 years, men onlyHealthy volunteers can take part
- Conditions the study is for
- Dihydrotestosterone, Periprosthetic Joint Infection (PJI), Cutibacterium Acnes
- What is being tested?
- Finasteride 1 mg
- Type of treatment
- Pill or oral medicine
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 40 participants
- Where
- No sites listed yet
- Study dates
- 31 Aug 2026to 31 Aug 2027
- Phase
- Phase 4
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 65 years
- Men only
- Healthy volunteers accepted
- Adult, Older adult
Who may be able to join
- 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
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- 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
Who cannot join
None listed.
Trial locations and contacts
No sites are listed yet. Contact the study team or a site near you to ask about taking part.
About this study
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:
Read more
- 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).
- Being tested
- Finasteride 1 mg, Placebo Control
- Keywords
- placebo, blood draw, skin culture
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Finasteride 1 mgDrug
Patients randomized to the experimental group will receive oral Finasteride 1 mg, taken daily, for two weeks
Placebo ControlDrug
Patients randomized to the placebo group will receive one pill containing no active medicine, taken daily, for two weeks.
| Study group | Role | What they receive |
|---|---|---|
| Finasteride group | Experimental | Not described Receives: Drug: Finasteride 1 mg |
| Placebo group | Placebo comparator | Not described Receives: Drug: Placebo Control |
What is being measured
The primary outcome is the main question the study is designed to answer.
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).
Measured: 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.
Measured: levels will be assessed at baseline and after 14 consecutive days of treatment or placebo.
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted28 Jul 2026
- Study start31 Aug 2026 (estimated)
- Primary completion31 Mar 2027 (estimated)
- Study completion31 Aug 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for DihydrotestosteroneStudies of the same condition, open and under way.
- More trials run by University of WashingtonThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 4
- Primary purpose
- Prevention
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Double blind
- Who is masked
- Participant, Care provider
- Enrolment
- 40 participants (estimated)
Sponsor and investigators
- Lead sponsor
- University of Washington
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Corey Schiffman, University of Washington
- Investigators
- Corey Schiffman, MD, Principal investigator, University of Washington
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07731802
- Sponsor's protocol ID
- STUDY00025632
- Status last verified
- Jul 2026
- First submitted
- 23 Jul 2026
- Last updated
- 28 Jul 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- Yes
- FDA-regulated device
- No