Ongoing, recruitingHuman Pharmacology (Phase I)- OtherInterventional

Crossover study to investigate the safety and tolerability as well as the blood levels after three single doses of Tacrolimus, of which 2 are administered via the cheek mucosa and 1 dose via the mouth (oral).

This early-stage study is exploring a medicine called Tacrolimus. Tacrolimus is already used to stop the body from rejecting transplanted organs like a liver, kidney, or heart. Researchers want to find out how safe it is and how well the body absorbs it when given in different ways. They are specifically testing giving the medicine through the cheek (inside the mouth) compared to swallowing it, in healthy adult men. The main goal is to understand how the medicine behaves in the body and check for any side effects. This information will help doctors decide the best way to give this medicine in the future.

At a glance

Status

Ongoing, recruiting

Phase

Human Pharmacology (Phase I)- Other

Sponsor

Nucleus Medical GmbH

Enrolment target

Start

04 Mar 2026

Phase I study in healthy male volunteers. Intended indication: prophylaxis of transplant rejection in liver kidney or heart allograft recipients and for treatment of allograft rejection

What is this study about?

This study is about a medicine called Tacrolimus, which is really important for people who have received an organ transplant. When someone gets a new liver, kidney, or heart, their body can sometimes try to reject it, like it's a foreign invader. Tacrolimus helps to prevent this rejection, allowing the new organ to work properly.

In this study, researchers are looking at new ways to give Tacrolimus. Currently, it's usually swallowed. However, they want to see if giving it through the cheek area (inside the mouth) might be another good option. This is called a 'crossover study', which means each participant will try different ways of taking the medicine at different times, allowing scientists to compare them directly.

This is a very early study, often called a 'Phase I' study. It's designed to understand how safe the medicine is when given in these different ways, and how much of it gets into the bloodstream. This information is crucial for future development, ensuring that any new way of giving the medicine is as safe and effective as possible for patients who need it most.

Key takeaways

This study is testing different ways to give Tacrolimus, a medicine for transplant patients.
It aims to check the safety and how the medicine is absorbed.
Healthy adult men are needed to take part.
Each participant will receive the medicine swallowed and through the cheek.
It's an early-stage study to gather important safety information.

Who may be eligible?

To take part in this study, you would need to be a healthy man. This is a very early study, so it's common for them to start with healthy volunteers to make sure the medicine is safe before testing it in patients who are unwell.

You also need to be an adult, aged 18 years or older. There is no upper age limit, meaning men of any age from 18 upwards can be considered.

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 male?
Are you 18 years old or older?
Do you generally consider yourself to be in good health?
Are you able to commit to the study visits and procedures?

Answer every question to see your result.

What does participation involve?

If you decide to take part, you would receive the study medicine, Tacrolimus, on three separate occasions. Two times, you would receive the medicine by placing it inside your cheek, and one time you would swallow it. This allows the researchers to compare how your body handles the medicine when given in different ways. They would regularly check your blood levels to see how much of the medicine is absorbed. You would also be monitored closely for any side effects. The total duration of your involvement in the study would depend on how many follow-up visits are needed after each dose to monitor your health and the medicine's effects.

Potential risks and benefits

Taking part in any study has potential benefits and risks. For healthy volunteers in this early study, the main benefit is helping to advance medical knowledge, potentially leading to better treatment options for transplant patients in the future. The risks involve potential side effects from the study medicine, which will be carefully monitored. You will be given a full explanation of known side effects. It's important to remember that you are free to withdraw from the study at any time, for any reason, without it affecting your 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
Germany

Common questions

What is Tacrolimus normally used for?

It's used to help stop the body from rejecting transplanted organs like a new liver, kidney, or heart.

Why are they giving the medicine through the cheek?

Researchers want to see if this new way of giving the medicine is safe and how well the body absorbs it compared to swallowing it.

Will I get the medicine in different ways?

Yes, you would receive the medicine through your cheek twice and swallow it once, allowing for comparison.

Who can take part in this study?

This early study is looking for healthy men, aged 18 or older.

What is a 'Phase I' study?

This is a very early stage of research, mainly focused on checking if a new treatment or way of giving medicine is safe and how it behaves in the body.