AuthorisedTherapeutic exploratory (Phase II)Interventional

Retinoic acid and sperm production in infertile men

This study aims to find out if a medicine called isotretinoin can improve sperm production in men who have a low sperm count. A low sperm count means a man has fewer sperm than usual, which can sometimes make it harder to have a baby. During the study, some men will receive the isotretinoin medicine, while others will receive a dummy pill (placebo). Researchers will measure sperm production after 20 weeks to see if there's a difference between the two groups. They will also look at how well the sperm move and what they look like. This research is in its early stages (Phase II) and is designed to explore whether this treatment could be helpful in the future.

At a glance

Status

Authorised

Phase

Therapeutic exploratory (Phase II)

Sponsor

Les Hopitaux Universitaires De Strasbourg

Enrolment target

100

Start

09 Apr 2026

oligozoospermia

What is this study about?

This study is investigating a problem called oligozoospermia, which is the medical term for having a lower-than-average number of sperm. For some men, this can make it more difficult to conceive a child. The research hopes to discover if a medication called isotretinoin, which is already used for other conditions, might help improve sperm production.

To do this, the study will involve two groups of men. One group will take isotretinoin tablets, and the other group will take a dummy pill (a placebo) that looks the same but contains no active medicine. This helps researchers compare the effects fairly to see if any changes are due to the medication itself. After 20 weeks of treatment, the main thing researchers will measure is the total number of sperm produced.

They will also look at other important aspects of sperm health, such as how well the sperm can move (sperm motility) and their shape (sperm morphology). By understanding these factors, the study aims to build a clearer picture of whether isotretinoin could be a useful treatment option for men with low sperm counts in the future. This is a Phase II trial, meaning it's an early-stage study to explore the effectiveness and safety of a treatment.

Key takeaways

The study investigates if isotretinoin helps men with low sperm counts.
It lasts for 20 weeks of weekly treatment.
Sperm count, movement, and shape will be measured.
Participants will receive either the study drug or a dummy pill.
This is an early-stage study to explore potential new treatments.

Who may be eligible?

To be part of this study, you need to be a man aged 18 years or older. There is no upper age limit, meaning men of any age beyond 18 can potentially join.

The study is specifically looking for men who have been diagnosed with a low sperm count. This medical condition is sometimes called oligozoospermia.

Could this study suit you?

Answer these quick questions to see if you may be eligible. This is a guide only — the research team makes the final call.

Are you a man?
Are you 18 years old or older?
Have you been diagnosed with a low sperm count?
Are you able to commit to weekly treatment for 20 weeks and regular clinic visits?

Answer every question to see your result.

What does participation involve?

If you join this study, you would take either the active medicine (isotretinoin) or a dummy pill (placebo) once a week for 20 weeks. You would have regular visits to the clinic so doctors can monitor your health and collect sperm samples. These samples will be used to measure your sperm production, how well your sperm move, and their shape. The total duration of your active involvement in the study, including all treatments and check-ups, would be around 20 weeks, plus any initial screening and final follow-up appointments.

Potential risks and benefits

Taking part in any medical study carries potential benefits and risks. A potential benefit of this study is that the treatment might improve your sperm count, which could make it easier to conceive. However, it's also possible you might receive the dummy pill and not experience any changes from the treatment. Isotretinoin, like all medicines, can have side effects, and these would be fully explained to you by the study team. You would be closely monitored throughout the study for any health changes. Remember, joining is completely voluntary, and you have the right to withdraw from the study at any time, for any reason, without it affecting your usual medical care.

Locations (1)

Some site locations are approximate. We're improving this — please verify with the trial team before travelling.

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Unverified
France

Common questions

What is a 'low sperm count'?

A low sperm count means that your semen (the fluid released when you ejaculate) contains fewer sperm than is considered normal. This can sometimes make it harder to have a baby.

What is isotretinoin?

Isotretinoin is a medicine that is currently used for other conditions, but this study is exploring if it could also help with sperm production.

What is a 'dummy pill'?

A dummy pill, also called a placebo, is a tablet that looks exactly like the study medicine but doesn't contain any active drug. It helps researchers compare the effects fairly.

Will I know if I'm getting the active medicine or the dummy pill?

No, during the study, neither you nor the study team will know whether you are receiving the active medicine or the dummy pill. This is done to prevent bias in the results.

How long will the study treatment last?

The treatment period for this study is 20 weeks, during which you will take the assigned tablet once a week.