Skip to content
Clinical Trials – home

Rare diseases

Investigational molecules

Locations

Our offerNewsroom

Recruiting

Study of PRAX-628 to evaluate safety and effectiveness in adults with epilepsy who have focal seizures or generalized tonic-clonic seizures

Fast replyInvestigationalNo placebo
Clinical Trials Concierge

Prefer not to search? Our Concierge searches the trials for you.

What is this trial about?

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

This clinical trial studies the use of vormatrigine (also known as PRAX-628) in adults who have epilepsy with either focal onset seizures or primary generalized tonic-clonic seizures. These types of seizures are different forms of epilepsy where electrical disturbances in the brain cause sudden, uncontrolled movements or changes in behavior.

The study aims to determine how safe and well-tolerated vormatrigine is when given to patients who have previously received this medication in other studies or through special access programs. The medication comes in the form of capsules that are taken by mouth. The treatment period may last up to 24 months.

During the study, doctors will monitor patients' health through various tests and check how well the medication is working to control seizures. They will pay special attention to any side effects that might occur during treatment and measure the amount of medication in patients' blood. The study will also track changes in the severity of the condition as observed by both doctors and patients.

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

    Initial participation

    You will be provided with vormatrigine in the form of oral capsules for treatment of focal onset seizures or primary generalized tonic-clonic seizures

    The study duration is from August 2025 to August 2027

  2. Step 2

    Medical monitoring

    Your health will be monitored through several medical tests:

    Regular checks of vital signs

    Laboratory tests of blood samples

    Heart monitoring through electrocardiogram (ECG)

    Assessment of mental health using a specific rating scale

  3. Step 3

    Seizure tracking

    You will need to maintain a seizure diary to record the frequency of seizures

    The diary should be completed regularly throughout the study period

  4. Step 4

    Regular assessments

    Your impression of the severity of your condition will be evaluated using a specific scale

    Medical professionals will assess the severity of your condition

    Blood samples will be taken to measure the levels of vormatrigine in your system

  5. Step 5

    Safety monitoring

    Any side effects that occur during the study will be recorded and monitored

    If side effects become severe, the study medication may need to be discontinued

Who can join the trial?

8 criteria

  • You must be willing to sign an informed consent document confirming that you understand the purpose and requirements of the clinical trial
  • You must have previously participated in specific clinical trials of vormatrigine (such as PRAX-628-212, PRAX-628-321) or received this medication through other approved programs
  • You must have shown good compliance with keeping a seizure diary (a record of your seizure activity) and taking the study medication as directed in previous trials
  • You must be an adult (18 years or older)
  • You can be either male or female
  • You must have a diagnosis of either focal onset seizures (seizures that start in one area of the brain) or primary generalized tonic-clonic seizures (seizures that affect the entire brain from the start)
  • You must be able to follow all study procedures and complete all required assessments
  • You must be willing to use appropriate contraception during the study period

Who cannot join the trial?

12 criteria

  • Age below 18 or above 65 years
  • Pregnant or breastfeeding women
  • History of allergic reactions to similar medications
  • Current participation in other clinical trials
  • Having seizures different from focal onset (seizures that start in one part of the brain) or primary generalized tonic-clonic seizures (seizures affecting the whole brain from the start)
  • Severe kidney or liver problems
  • Uncontrolled high blood pressure
  • History of drug or alcohol abuse within the past 2 years
  • Major psychiatric disorders
  • Use of medications that could interact with the study drug
  • Having other serious medical conditions that could interfere with the study
  • Unable to follow study procedures or attend scheduled visits
Clinical Trials Concierge

Prefer not to search? Our Concierge searches the trials for you.

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.

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

Vormatrigine is an investigational medication being studied for the treatment of epilepsy. It is designed to help control both focal seizures (which affect one part of the brain) and primary generalized tonic-clonic seizures (which affect the entire brain). This medication aims to reduce the frequency and severity of seizures in adult patients.

What is already known about the treatment

Vormatrigine - An investigational anticonvulsant medication administered orally for the treatment of epilepsy, specifically targeting focal onset seizures and primary generalized tonic-clonic seizures. This novel drug is currently undergoing clinical trials to evaluate its safety and tolerability in adult patients, representing a potential new option in the antiepileptic drug category. While the exact molecular mechanism involves modulation of neuronal sodium channels to reduce excessive electrical activity in the brain, the drug shows promise in seizure control based on preliminary studies. The medication belongs to the pharmacological class of anticonvulsants and is being developed as a potential addition to the current therapeutic options for epilepsy management.

Investigated diseases

  • Focal Onset Seizures

    A type of epileptic seizure that begins in one area of the brain. These seizures can cause various symptoms depending on which brain area is affected, including twitching, unusual sensations, or changes in awareness. The person may remain conscious but experience altered awareness, or consciousness may be impaired. These seizures can sometimes spread to involve both sides of the brain.

  • Primary Generalized Tonic-Clonic Seizures

    A type of seizure that affects both sides of the brain from the start. The seizure begins with stiffening of the muscles (tonic phase), followed by rhythmic jerking movements (clonic phase). During these seizures, a person loses consciousness, and their muscles contract and relax repeatedly. These seizures typically last for a few minutes and affect the entire body.

Trial detailsLast updated 7 Oct 2026
Age18+ yearsPhasePhase IIITrial ID2025-521640-38-00Protocol codePRAX-628-323Estimated enrolment196 patientsSponsorPraxis Precision Medicines 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? Our Concierge searches the trials for you.

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