A Phase 2 interventional study of isotretinoin and Human chorionic gonadotrophin (hCG) in Oligospermia, Azoospermia, Nonobstructive and Infertility, sponsored by University of Nebraska. Enrolling by invitation at 1 site in United States. Open to male participants aged 19 Years to 50 Years. Per ClinicalTrials.gov, last updated 2026-04-20.
Sponsored by University of Nebraska · Phase 2, Interventional, and Treatment
This study compares two medical treatments to see how well they improve sperm production in men with infertility due to low sperm counts (oligospermia) or no sperm in the semen due to non-obstructive causes (nonobstructive azoospermia). Some men with these conditions have limited nonsurgical treatment options, and current therapies do not work for everyone.
Participants in this study will be adult men ages 19 to 50 who have been diagnosed with oligospermia or nonobstructive azoospermia and do not have a correctable cause for infertility. Eligible participants will be randomly assigned to receive one of two treatments for three months: oral isotretinoin taken twice daily, or human chorionic gonadotropin (hCG) injections given three times per week. hCG is a standard hormonal therapy used in certain types of male infertility, while isotretinoin is being studied for its potential role in stimulating sperm production.
At the start of the study, participants will have blood tests to measure reproductive hormone levels and a semen analysis. Blood tests will be repeated at one month and three months, and a repeat semen analysis will be performed at three months, which corresponds to a full cycle of sperm development. The main goal of the study is to determine whether motile (moving) sperm appear in the semen after treatment. Additional goals include measuring changes in sperm count and hormone levels, as well as monitoring medication side effects.
Both study medications are FDA-approved and have known side effect profiles. Participants may or may not experience improvement in sperm production. The results of this study may help guide future treatment options for men with infertility due to low or absent sperm production.
64 studies on the registry are indexed under Oligospermia; 17 are open to participants now.
This study's planned enrollment of 100 is above the median of 65 across 46 interventional studies indexed under Oligospermia.
Browse Oligospermia studies →University of Nebraska is the lead sponsor of 496 studies on the registry; 67 are open to participants now.
Of its 83 completed or terminated interventional studies of FDA-regulated products, 53 (64%) have results posted.
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Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
A planned gap after a treatment, so that its effects can lessen before the study treatment or a study assessment. Ask the study team and the doctor who prescribed it before changing any medicine.
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Washout period
A planned gap after a treatment, so that its effects can lessen before the study treatment or a study assessment. Ask the study team and the doctor who prescribed it before changing any medicine.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraindication
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Cancer (malignancy)
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Participants in this arm will receive oral isotretinoin 20 mg twice daily for 3 months. Reproductive hormone testing will be performed at baseline, 1 month, and 3 months, and a semen analysis will be repeated at 3 months to assess treatment response.
Drug: isotretinoin
Participants in this arm will receive human chorionic gonadotropin (hCG) injections at a dose of 2,000 units three times weekly for 3 months. Reproductive hormone testing will be performed at baseline, 1 month, and 3 months, and a semen analysis will be repeated at 3 months to assess treatment response
Drug: Human chorionic gonadotrophin (hCG)
Oral isotretinoin administered at a dose of 20 mg twice daily for 3 months as part of a randomized treatment arm evaluating effects on sperm production and reproductive hormone levels.
Human chorionic gonadotropin (hCG) administered by subcutaneous injection at a dose of 2,000 units three times weekly for 3 months as part of a randomized treatment arm evaluating effects on sperm production and reproductive hormone levels.
Presence of Motile Sperm in the Ejaculate
Assessment of whether motile (moving) sperm are present in the ejaculate following treatment with isotretinoin or human chorionic gonadotropin (hCG), as determined by standard semen analysis
Time frame: 3 months
Plan to share: No
No publications or documents are linked to this record.
Started Apr 2026 (actual). Primary completion is estimated for Jun 2027, 14 months after the start.
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Studies of the drug tested here: Isotretinoin