Men · California
Studies open only to men in California
These studies list male participants only in their official record. Most other studies accept everyone regardless of sex.
33 recruiting studiesSource: ClinicalTrials.gov, refreshed October 26, 2026How we list studies
Studies
- RecruitingHealthy volunteersPhase 1
A Study to Evaluate the Effect of Food on the Bioavailability of AJ201, and Safety, Tolerability, and Pharmacokinetics of AJ201 in Japanese and White Healthy Male Participants
AnnJi Pharmaceutical Co., Ltd.
- Location
- Los Alamitos, CA
- Eligibility basics
- Ages 18–55 · Men only
- RecruitingHealthy volunteersPhase 1/Phase 2
Spermatogonial Differentiation Via Testicular Organoid
CellARTs Inc.
- Location
- San Francisco, CA
- Eligibility basics
- Ages 18–60 · Men only
- RecruitingHealthy volunteers
ProACT Post-Approval Study
Uromedica
- Location
- Los Angeles, CA + 13 other US sites
- Eligibility basics
- Ages 50+ · Men only
- RecruitingHealthy volunteers
Efficacy of Qualia Testosterone+ on Testosterone Levels in Adult Males
Qualia Life Sciences
- Location
- Carlsbad, CA
- Eligibility basics
- Ages 28–65 · Men only
- RecruitingHealthy volunteers
Prospective Study on Power Prenatal Vitamins for Males on YO Score At-home Sperm Test Results
The Bird and Be Co Inc
- Location
- Encino, CA
- Eligibility basics
- Ages 18–50 · Men only
- RecruitingPhase 2/Phase 3
Phase 2/3 Efficacy and Safety of PP405 in Adult Males
Pelage Pharmaceuticals, Inc.
- Location
- Manhattan Beach, CA + 26 other US sites
- Eligibility basics
- Ages 18–55 · Men only
- RecruitingPhase 1/Phase 2
A Study to Investigate the Safety and Effectiveness of a Coagulation Factor IX Gene Insertion Therapy (REGV131-LNP1265) in Pediatric, Adolescent and Adult Participants With Hemophilia B
Regeneron Pharmaceuticals
- Location
- Los Angeles, CA + 16 other US sites
- Eligibility basics
- Ages 2+ · Men only
- RecruitingPhase 1
A Study to Learn About How Changing Therapy From Emicizumab to Marstacimab Affects People With the Severe Hemophilia A.
Pfizer
- Location
- Los Angeles, CA + 2 other US sites
- Eligibility basics
- Ages 12–74 · Men only
- RecruitingPhase 1/Phase 2
A Gene Therapy Study of SPK-8011QQ in Adults With Severe or Moderately Severe Hemophilia A
Hoffmann-La Roche
- Location
- Orange, CA + 5 other US sites
- Eligibility basics
- Ages 18+ · Men only
- RecruitingPhase 1/Phase 2
A Study to Evaluate the Safety, Tolerability, Pharmacokinetics, Pharmacodynamics, and Efficacy of NXT007 in Persons With Severe or Moderate Hemophilia A
Hoffmann-La Roche
- Location
- Sacramento, CA + 2 other US sites
- Eligibility basics
- Ages 2–59 · Men only
- RecruitingPhase 1/Phase 2
ATTUNE: A Study to Evaluate the Safety, Tolerability, Pharmacokinetics, and Pharmacodynamics of Intrathecally-Administered ION440 in Participants With Methyl CpG Binding Protein 2 (MECP2) Duplication Syndrome (MDS)
Ionis Pharmaceuticals, Inc.
- Location
- San Diego, CA + 7 other US sites
- Eligibility basics
- Ages 2–65 · Men only
- RecruitingPhase 3
Safety and Effectiveness of Giroctocogene Fitelparvovec or Fidanacogene Elaparvovec in Patients With Hemophilia A or B Respectively
Pfizer
- Location
- Rancho Cordova, CA + 12 other US sites
- Eligibility basics
- Ages 18+ · Men only
- RecruitingPhase 2
A Gene Therapy Study of RP-A501 in Male Patients With Danon Disease
Rocket Pharmaceuticals Inc.
- Location
- La Jolla, CA + 2 other US sites
- Eligibility basics
- Ages 8+ · Men only
- Recruiting
Post-Market Study to Assess iTind Safety in Comparison to UroLift
Olympus Corporation of the Americas
- Location
- Fresno, CA + 10 other US sites
- Eligibility basics
- Ages 50+ · Men only
- RecruitingPhase 2
Study of MRM-3379 in Male Participants With Fragile X Syndrome (BLOOM)
Mirum Pharmaceuticals, Inc.
- Location
- Irvine, CA + 13 other US sites
- Eligibility basics
- Ages 13–45 · Men only
- RecruitingPhase 1/Phase 2
Safety, PK/PD, and Exploratory Efficacy Study of AMT-191 in Classic Fabry Disease
UniQure Biopharma B.V.
- Location
- Los Angeles, CA + 9 other US sites
- Eligibility basics
- Ages 18–65 · Men only
- RecruitingPhase 4
A Study to Test a Medicine (Fitusiran) for Preventing Bleeds in People With Severe Hemophilia Who Previously Received Preventive Treatment With Emicizumab
Sanofi
- Location
- Los Angeles, CA + 1 other US site
- Eligibility basics
- Ages 12+ · Men only
- RecruitingPhase 1
A Gene Transfer Therapy Study to Evaluate the Safety of and Expression From Delandistrogene Moxeparvovec (SRP-9001) in Participants With Duchenne Muscular Dystrophy (DMD) - Non-Ambulatory Cohort
Sarepta Therapeutics, Inc.
- Location
- La Jolla, CA + 10 other US sites
- Eligibility basics
- Ages 2+ · Men only
- Recruiting
A Clinical Study to Evaluate the Safety and Efficacy of the FloStent in Men With Benign Prostatic Hyperplasia Symptoms
Rivermark Medical
- Location
- Bakersfield, CA + 18 other US sites
- Eligibility basics
- Ages 45+ · Men only
- RecruitingPhase 2
A Clinical Trial Evaluating the Efficacy and Safety of Leflutrozole on Testicular Function
ReproNovo Aps
- Location
- North Hollywood, CA + 3 other US sites
- Eligibility basics
- Ages 18–49 · Men only
- Recruiting
Computer-Assisted Hair Restoration Study Using ARTAS System
Venus Concept
- Location
- San Jose, CA
- Eligibility basics
- Ages 20–70 · Men only
- RecruitingHealthy volunteers
Combatting HIV Or Other STIs Early (CHOOSE)
Westat
- Location
- San Francisco, CA + 5 other US sites
- Eligibility basics
- Ages 13–24 · Men only
- RecruitingHealthy volunteersPhase 3
Screening for Prostate Cancer Using High Resolution Micro-ultrasound Versus Multiparametric Magnetic Resonance Imaging.
University of Alberta
- Location
- Los Angeles, CA
- Eligibility basics
- Ages 50–70 · Men only
- RecruitingHealthy volunteers
Health-E You Efficacy Trial for Male Adolescents
Johns Hopkins University
- Location
- Oakland, CA + 7 other US sites
- Eligibility basics
- Ages 13–21 · Men only