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Relative bioavailability of BI 685509 tablets and the impact of food and esomeprazole on BI 685509 in healthy male volunteers

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What is this trial about?

A plain-language summary of the goals, design and what participants do

The study involves healthy adult volunteers and is designed to compare two different tablet forms of the experimental medicine BI 685509. The investigation also looks at how taking food and a common acid‑reducing drug called esomeprazole may change the amount of BI 685509 that reaches the bloodstream.

The purpose of the trial is to find out how much of the medicine is absorbed under different conditions. Participants will receive each tablet type on separate occasions while fasting, after a standard meal, and while also taking the acid‑reducing drug, with a short break between each period. Small blood samples will be taken after each dose to measure the drug levels over time, using simple terms such as the total exposure (how much drug is in the blood overall) and the peak level (the highest amount found). The study does not involve any patients with disease, and no additional medical procedures are required beyond the tablet intake and blood draws.

The research process

The trial runs in 5 steps – from screening to follow-up. Each step says what happens and what the team monitors.

  1. Step 1

    Randomisation and treatment schedule

    After joining the study you will be assigned to a specific order of four treatment periods. the order is decided by the study staff and you will receive written instructions for each period.

  2. Step 2

    First period – bi 685509 alone under fasted conditions

    You will fast (no food or drink except water) for at least ten hours before the visit.

    On the scheduled day you will take one bi 685509 tablet containing 3 mg by mouth. the tablet is taken once and no other medication is taken at the same time.

    Blood samples will be collected at several time points after the dose to measure how much drug is in the blood.

  3. Step 3

    Second period – bi 685509 with esomeprazole under fasted conditions

    You will again fast for at least ten hours before the visit.

    On the study day you will first take one esomeprazole tablet containing 40 mg by mouth. after the esomeprazole dose, you will take one bi 685509 tablet containing 3 mg by mouth.

    Both tablets are taken once and no food is eaten before the doses.

    Blood samples will be collected after the bi 685509 dose to assess the effect of esomeprazole on drug levels.

  4. Step 4

    Third period – bi 685509 after a standardized meal (fed condition)

    You will eat a standardized meal provided by the study staff. the meal is consumed within thirty minutes.

    Immediately after finishing the meal you will take one bi 685509 tablet containing 3 mg by mouth.

    The tablet is taken once and no additional medication is taken at this time.

    Blood samples will be collected after the dose to evaluate how food influences the drug level.

  5. Step 5

    Fourth period – reference bi 685509 tablet under fasted conditions

    You will fast for at least ten hours before the visit.

    On the study day you will take one reference bi 685509 tablet containing 3 mg by mouth. this tablet is taken once and no other medication is taken at the same time.

    Blood samples will be collected after the dose to compare the reference tablet with the test tablet.

Who can join the trial?

5 criteria

  • Healthy men or women who are judged by the doctor to be in good health after a full medical check‑up, including a physical exam, blood pressure and pulse check, a heart test called a 12‑lead ECG, and routine lab tests.
  • Age between 18 and 55 years (including both 18 and 55).
  • Body weight measured as body mass index (BMI) from 18.5 to 29.9 kilograms per square meter, which is a standard way to assess if a person’s weight is in a normal range for their height.
  • Must sign and date a written informed consent form, showing you understand the study and agree to take part.
  • Additional requirements may be needed as determined by the study team.

Who cannot join the trial?

5 criteria

  • If any part of the medical check‑up (for example, blood pressure, pulse rate or a heart‑electrical test called an ECG) is abnormal and the doctor decides it is important, you cannot join the study.
  • If repeated measurements show your systolic blood pressure (the top number) is not between 90 and 140 mmHg, your diastolic blood pressure (the bottom number) is not between 50 and 90 mmHg, or your pulse rate is not between 45 and 90 beats per minute, you cannot join the study.
  • If any laboratory value (such as a blood or urine test) falls outside the normal reference range and the doctor thinks it is important, you cannot join the study.
  • If you have any other ongoing illness that the doctor judges to be important (concomitant disease), you cannot join the study.
  • There are additional reasons that may also prevent participation, as the study includes other exclusion criteria not listed here.
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Investigated drugs

  • BI 685509

    is an experimental oral tablet being studied for how it is absorbed in the body. The trial compares two different tablet versions of this drug, looks at how food changes its absorption, and also checks what happens when it is taken together with a stomach‑acid‑reducing medicine. The goal is to understand the best way to give this medication so that it works well.

  • Esomeprazole

    is a medicine that lowers stomach acid. In this study it is used to see whether reducing stomach acid affects the way BI 685509 is absorbed when both drugs are taken at the same time. This helps researchers learn if the acid‑lowering drug changes the safety or effectiveness of the test medication.

What is already known about the treatment

  • Nexium mups 40 mg magensaftresistente Tabletten

    This gastro‑resistant tablet is taken by mouth and dissolves only after it passes the stomach. Esomeprazole magnesium trihydrate is an approved medication that is widely used to treat heartburn, acid reflux and ulcer disease. It works by blocking a tiny pump in stomach cells that makes acid, lowering the amount of acid that is produced. It belongs to the drug class called proton‑pump inhibitors.

  • BI 685509

    This film‑coated tablet is also taken by mouth and is being studied in clinical trials. BI 685509 is an investigational compound that has not yet received marketing approval and is currently only described in research literature. It is thought to act on specific proteins in the body that may influence disease processes, although the exact molecular target is still being clarified. It is classified as an experimental small‑molecule oral drug.

Investigated diseases

Conditions this trial is registered against

Trial detailsLast updated 2 Oct 2026
Age18+ yearsPhasePhase ITrial ID2023-506367-33-00Protocol code1366-0042Estimated enrolment16 patientsSponsorBoehringer Ingelheim International GmbH

sourced from the EU Clinical Trials Register and site verification

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On this site, “treatment” means an investigational medicine being studied in a clinical trial. Its safety and efficacy for the use being studied have not yet been confirmed, some participants may receive a placebo or a comparator medicine, and taking part does not guarantee any health benefit. The decision to take part is made by the doctor at the research site. This site is for information only and does not replace medical advice.

This service is not affiliated with the European Commission, the EMA, or the official CTIS system. Most information comes from publicly available international clinical-trial registries, supplemented by data from academic sites, national regulators and commercial sponsors. On this site, “treatment” and “therapy” mean a medicine being tested in a clinical trial. Its safety and effectiveness in the use being studied are not yet confirmed, some participants may receive a placebo or a comparator, and taking part does not guarantee a health benefit. The doctor at the research site decides who can take part. This site provides information, not medical advice. Certain content and visual elements on this website have been generated or enhanced using artificial intelligence (AI).