Effects of NLS-133, a Potential Non-Hormonal "On-Demand" Male Contraceptive (NCT07393334) | Clinical Trial Compass
RecruitingPhase 2
Effects of NLS-133, a Potential Non-Hormonal "On-Demand" Male Contraceptive
United States10 participantsStarted 2025-12-02
Plain-language summary
NLS-133-CLIN001 is a Phase 2a study designed to assess the safety, tolerability, and effects of NLS-133 (combination of two FDA-approved agents) compared to an active control (FDA-approved pharmacologic agent) or placebo on semen volume and sperm count in 10 in healthy men. Participants will be randomized in a crossover design to receive a single dose of NLS-133, an active control or placebo either 90 or 180 minutes prior to collection of semen. Sperm parameters measured will be count, motility and morphology. A brief questionnaire will be completed by each subject during each treatment cycle that addresses orgasm and ejaculation quality. Safety monitoring will include adverse event reporting, laboratory assessments, and vital signs.
Who can participate
Age range
18 Years – 55 Years
Sex
MALE
See this in plain English?
AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.
Inclusion criteria
. Male, age 18-55.
. Normal physical examination and testicular volume \>15 cc
. No significant medical history that would impact the safety of the study.
. No current use of drugs that comprise NLS-133
. Normal values on baseline hematology, blood chemistry and liver function tests and serum testosterone.
. Normal baseline sperm parameters (semen volume \>1.4 cc, sperm concentration \>15 million/ml, motility \>40% and morphology \>4%).
. Willing and able to comply with all study requirements and procedures.
Exclusion criteria
Questions worth asking your doctor
Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.
1Based on my diagnosis and history, is this trial worth exploring for me — or is there a standard treatment we should try first?
2What does this trial's phase tell us about how much is already known about its safety and benefit?
3What would taking part actually involve for me — visits, tests, time, and travel?
4What are the known and possible risks or side effects I should weigh, and how would they be monitored?
5If this trial isn't the right fit, what other options or trials would you suggest I look into?
Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.
Questions for the trial coordinator
The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.
1What does taking part actually involve week to week — how many visits, where, and how long does each one take?
2What costs are covered by the study, and what might I have to pay for myself, including travel, parking, or time off work?
3What happens during screening, and what happens if the study team confirms I don't meet the criteria after those tests?
4Who pays for the scans, blood work, and other tests the trial requires — the study, my insurance, or me?
5How will being in the trial affect my regular care, and will my own doctor stay informed and involved?
6Can I leave the trial at any point if I change my mind, and what would happen to my care if I do?
A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.
What they're measuring
1
Semen volume (mL)
Timeframe: 90 and 180 minutes for each treatment cycle
2
Sperm count (millions/mL)
Timeframe: 90 and 180 minutes for each treatment cycle
. Inability to produce semen samples in clinic setting.
. Significant chronic or acute medical illness.
. Previous or current ethanol or illicit drug abuse.
. Evidence of significant underlying disease (based on results of the physical exam and the routine labs).
. Known infertility or hypogonadism.
. Planned or anticipated use of any prohibited medications during participation in the study. These include use of sex hormones for treatment, testosterone, anabolic steroids, retinoic acid (e.g., Accutane®), vitamin A, other drugs known to inhibit spermatogenesis, opioids, cocaine, methamphetamine, and/or the consumption of \>4 alcoholic beverages daily.
. Presence of moderate-to-severe pulmonary or cardiovascular disease