Skip to content
Clinical Trials – home

Rare diseases

Investigational molecules

Locations

Our offerNewsroom

Not yet recruiting

Phase 3 Randomized Study of RAP-219 to Reduce Seizure Frequency in Adults with Focal Epilepsy

Verified siteInvestigational
Clinical Trials Concierge

Prefer not to search on your own, or looking for clinical trials for a rare disease?

What is this trial about?

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

The study involves adults diagnosed with Epilepsy who experience focal seizures, which are seizures that start in one part of the brain. The investigational medication being tested is called RAP-219, an oral tablet that is compared with an inactive pill (placebo). The goal is to determine whether RAP-219 can lower the number of seizures a person has.

This is a Phase 3 trial, meaning it is a late‑stage test to confirm how well the drug works and how safe it is. Participants are assigned by chance (randomized) to receive either RAP-219 or the placebo, and neither the participants nor the study staff know which treatment is given (double‑blind). After a short initial period, the assigned treatment is taken for several weeks while participants keep a diary of seizures and attend regular check‑ins at the study site.

During the study, researchers look at how often seizures occur, how many days a participant goes without a seizure, and any side effects or changes in health measurements such as blood tests or heart rhythm checks. The information collected helps assess whether RAP-219 provides a meaningful reduction in seizure frequency compared with the placebo.

The research process

The trial runs in 10 steps – from screening to follow-up. Each step says what happens and what the team monitors.

  1. Step 1

    Randomization and Assignment

    After you join the study, you will be randomly assigned to receive either the active medication RAP‑219 or a matching placebo. The assignment is done by a computer system so that neither you nor the study staff know which product you receive.

  2. Step 2

    Baseline Assessment

    Before starting any medication, you will undergo a series of baseline assessments. These include a physical exam, vital‑sign measurements, an electrocardiogram (ECG) to check heart rhythm, blood tests for complete blood count and chemistry, and a review of your seizure history. You will also complete questionnaires that measure seizure severity and quality of life.

  3. Step 3

    Start of Double‑Blind Treatment

    Once the baseline assessments are complete, you will begin the double‑blind treatment phase. You will receive tablets that are taken by mouth. Each tablet is labeled as containing 0 mg of the study substance, which reflects the way the dose is recorded in the study database. The tablets are taken once daily.

  4. Step 4

    Daily Medication Use

    You will swallow one tablet each day at roughly the same time each day. The tablets look identical whether they contain RAP‑219 or the placebo, and you will not be told which one you have.

  5. Step 5

    Regular Study Visits

    During the treatment phase you will attend scheduled visits, typically every four weeks. At each visit you will have vital signs checked, an ECG performed, and blood drawn for safety laboratory tests. The study staff will also ask about any adverse events, such as side effects or new health problems.

  6. Step 6

    Seizure Diary Recording

    You will keep a daily seizure diary in which you record the date, time, and type of each seizure you experience. The diary is used to calculate seizure frequency for the study’s primary and secondary outcomes.

  7. Step 7

    Maintenance Period Evaluation

    Every 28‑day period during the double‑blind phase is considered a maintenance interval. At the end of each interval the study team will compare the number of seizures you recorded with the number recorded before treatment started. This comparison determines whether you have achieved a reduction of at least 50 % in seizure frequency.

  8. Step 8

    End of Double‑Blind Treatment

    The double‑blind treatment continues until the planned end of the study or until you discontinue early because of a safety concern or personal choice. At the final treatment visit, you will stop taking the study tablets.

  9. Step 9

    Final Study Assessments

    After the last dose, you will undergo the same set of assessments performed at baseline, including vital signs, ECG, blood tests, and seizure questionnaires. The final seizure diary will also be collected.

  10. Step 10

    Study Completion

    Once all final data are collected, the study is considered complete for you. The study staff will inform you that no further study‑related procedures are required.

Who can join the trial?

6 criteria

  • Be between 18 and 75 years old.
  • Have a body mass index (BMI) from 18 to 45 kg/m² (BMI is a number that compares your weight to your height).
  • Have been diagnosed with focal epilepsy for at least 24 months before the first study visit (focal epilepsy means seizures start in one specific part of the brain).
  • Have at least one brain MRI or CT scan and one EEG done within the past 10 years, both showing findings that match a focal epilepsy diagnosis (MRI and CT are imaging tests that create pictures of the brain; EEG records the brain’s electrical activity).
  • Be taking between one and three regular antiseizure medicines (these are medications used every day to prevent seizures) and not rely only on rescue or “as needed” (PRN) seizure medicines.
  • Be able to keep a daily record of each focal seizure using an electronic diary (a digital tool for tracking seizures each day).

Who cannot join the trial?

9 criteria

  • Known hypersensitivity (allergy) to RAP‑219 or having taken RAP‑219 before.
  • Having a serious medical, brain (neurologic), or mental health (psychiatric) condition that is not stable or is likely to come back.
  • Expecting to need any surgery while the study is being done.
  • Having a history of generalized epilepsy, a type of seizure that starts in both sides of the brain.
  • Having only focal aware non‑motor seizures (seizures where you stay aware but have no obvious movements).
  • Having psychogenic nonepileptic seizures (seizure‑like events caused by psychological factors, not by epilepsy).
  • Having had status epilepticus or seizure clusters (many seizures that cannot be counted separately) within the past 12 months.
  • Having had epilepsy surgery within the past 12 months.
  • Participating in another clinical study of a new drug (investigational product) within the last 12 weeks or before that drug has cleared from the body (about five half‑lives).
Clinical Trials Concierge

Prefer not to search on your own, or looking for clinical trials for a rare disease?

Tell us about your condition – we search every trial in Europe and connect you with the right site.

We usually reply within a few days

Verified sites

All sites with verified contact details – recruitment status may not be available; ask directly

Trial locations

Where you can join this trial

Countries are shaded by recruitment status. Click a recruiting country to ask about joining there.

Not yet recruiting
Not finding your country?

Not sure what to do next?

Joining a clinical trial can seem overwhelming. We guide you step by step, so you know exactly what to expect and how we support you through the process.

See the full process and FAQ

Investigated drugs

RAP-219 is an experimental oral tablet being studied to see if it can lower the number of focal seizures in adults. In this trial, participants take the tablet by mouth, and researchers compare how often they have seizures while on RAP-219 versus a placebo. The goal is to find out whether RAP-219 can safely reduce seizure frequency and improve overall seizure control.

What is already known about the treatment

3-(7-chloro-1H-indazol-5-yl)-2,5-bis(trifluoromethyl)-3H-imidazo[4,5-b]pyridine - The drug is taken as an oral tablet that patients swallow whole. It is currently an investigational compound that has not yet received regulatory approval and is being studied in clinical trials for epilepsy. It is intended to treat focal seizures in adults by reducing abnormal electrical activity in the brain, likely through blocking specific ion channels that control neuron firing. It belongs to the class of small‑molecule antiepileptic agents.

Investigated diseases

Epilepsy - Epilepsy is a brain disorder marked by recurrent seizures, which are brief episodes of abnormal electrical activity. Seizures can cause loss of awareness, shaking, or unusual sensations. The frequency and type of seizures may change over time, influencing daily activities.
Trial detailsLast updated 13 Nov 2026
Age18+ yearsPhasePhase IIITrial ID2025-524847-11-01Protocol codeRAP-219-FOS-301Estimated enrolment189 patientsSponsorRapport Therapeutics Inc.

sourced from the EU Clinical Trials Register and site verification

Want to learn more about this trial or check if you can participate?

Clinical Trials Concierge

Prefer not to search on your own, or looking for clinical trials for a rare disease?

Tell us about your condition – we search every trial in Europe and connect you with the right site.