AuthorisedHuman Pharmacology (Phase I)- OtherInterventional

A study to investigate a potential effect of rilzabrutinib (SAR444671) on ethinylestradiol and levonorgestrel from combined oral contraceptives in healthy female participants

This study is investigating a new medicine called rilzabrutinib, which is being developed for a condition called Immune Thrombocytopenia Purpura. However, this particular phase of the study isn't about treating that condition directly. Instead, it's focusing on how rilzabrutinib might interact with common birth control pills containing ethinylestradiol and levonorgestrel. The main goal is to find out if taking rilzabrutinib could change how well these birth control pills work in healthy women. This is a very early-stage study, often called a Phase 1 study, which helps us understand how new medicines behave in the human body, especially when taken with other common medications. Understanding these interactions is crucial for patient safety.

At a glance

Status

Authorised

Phase

Human Pharmacology (Phase I)- Other

Sponsor

Sanofi-Aventis Recherche & Developpement

Enrolment target

Start

11 May 2026

Immune Thrombocytopenia Purpura

What is this study about?

This research study is about a new medicine called rilzabrutinib. While medicines like this are often developed to treat specific health problems, this particular part of the study isn't about treating any illness. Instead, it's a very important step to understand how this new drug behaves in the body, especially when someone might be taking other common medicines at the same time.

The main focus here is to see if rilzabrutinib changes how birth control pills work. Many women use birth control containing ingredients like ethinylestradiol and levonorgestrel, and it's really important to know if a new medicine could make them less effective. This study will carefully look at how these two types of medicines interact in healthy women. If rilzabrutinib were to reduce the effectiveness of birth control, that would be important information for doctors and patients and could mean that different birth control methods might be needed.

This type of study is called a 'human pharmacology' study, or often a 'Phase 1' study. These are some of the first studies involving humans after extensive lab testing. They are essential for gathering basic safety information and understanding how a drug moves through and is processed by the body. The information gathered from studies like this helps to ensure that new medicines can be used safely and effectively by patients in the future.

Key takeaways

This study is testing interaction between a new drug and birth control pills.
It's for healthy women aged 18 and over.
The goal is to ensure birth control pills remain effective when taken with the new drug.
This is an early-stage safety study, not a treatment study.
Participation involves taking medicines and having regular checks.
There's no direct health benefit, but it helps medical science.

Who may be eligible?

To join this study, participants must be healthy women, meaning they shouldn't have any significant ongoing health problems or illnesses that could affect the study results. You also need to be at least 18 years old, with no upper age limit specified, so adult women of any age could potentially take part.

Because the study is specifically looking at how the new medicine interacts with birth control pills, participants will need to be women who are currently using combined oral contraceptives (birth control pills that contain both ethinylestradiol and levonorgestrel) and are willing to continue using them throughout the study. You would also need to be able to understand and agree to all the study procedures.

There would be specific health checks and tests as part of the screening process to make sure you're suitable and safe to participate. For example, you might not be able to join if you have certain medical conditions, take other specific medications that could interfere with the study, or if you are pregnant or breastfeeding.

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 woman?
Are you 18 years old or older?
Are you generally healthy?
Are you currently taking a combined oral contraceptive pill (like brands containing ethinylestradiol and levonorgestrel)?
Are you willing to attend regular study appointments?

Answer every question to see your result.

What does participation involve?

If you decide to take part in this study, you would first go through a screening process to make sure you meet all the requirements. This would involve some health checks and tests. If you're eligible, you would then attend several study visits.

During the study, you would receive the study medicine, rilzabrutinib, and continue taking your usual birth control pills. Researchers would regularly take blood and urine samples to check how the medicines are affecting your body and how they interact. There would also be regular check-ups to monitor your general health and well-being.

We don't have all the exact details of the number of visits or the total length of the study here, but typically, these early-stage interaction studies involve a period of taking the study medication, followed by monitoring. The total duration could range from a few weeks to a couple of months, with regular appointments throughout.

Potential risks and benefits

Taking part in any study has potential benefits and risks. A potential benefit of taking part is contributing to medical knowledge that could help future patients use new medicines more safely. There is no direct personal health benefit expected as this study is not treating a condition. Potential risks could include side effects from the study medication, rilzabrutinib, or from the interaction between rilzabrutinib and your birth control pills. There's also a possibility that your birth control could become less effective, which would be discussed and managed by the study team. You always have the right 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 rilzabrutinib, and what is Immune Thrombocytopenia Purpura?

Rilzabrutinib is a new experimental medicine. Immune Thrombocytopenia Purpura (ITP) is a blood disorder where the body's immune system mistakenly attacks and destroys its own platelets, which are tiny cells that help blood to clot.

Will taking part in this study treat my ITP?

No, this study is not designed to treat ITP. It's an early-stage study focusing on how rilzabrutinib interacts with birth control pills in healthy women.

What kind of birth control pills are being studied?

The study is looking at combined oral contraceptives, which are birth control pills containing the ingredients ethinylestradiol and levonorgestrel.

Do I have to stop my birth control if I join the study?

No, you will be asked to continue taking your usual combined oral contraceptives throughout the study as the main purpose is to see how they interact with the new medicine.

What if my birth control becomes less effective during the study?

The study team will monitor for this. They will provide clear guidance on what to do and might recommend additional methods of contraception if there's a concern about reduced effectiveness.