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Study on Troriluzole for Patients with Obsessive Compulsive Disorder Not Responding to Current Treatment

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What is this trial about?

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

This clinical trial is focused on studying Obsessive Compulsive Disorder (OCD), a condition characterized by unwanted and repeated thoughts, feelings, ideas, or behaviors that make a person feel driven to do something. The study is investigating a treatment called Troriluzole, which is being tested as an additional therapy for individuals with OCD who have not responded adequately to their current treatment. Troriluzole is taken in the form of a capsule and is being compared to a placebo to evaluate its effectiveness.

The purpose of the study is to assess how well Troriluzole works in improving OCD symptoms. Participants will continue their current OCD medication while taking either Troriluzole or a placebo. The study will monitor changes in the severity of OCD symptoms over time, using a standard measurement tool known as the Y-BOCS score, which helps to quantify the severity of obsessive-compulsive symptoms.

Throughout the study, participants will be asked to take the medication orally for a period of up to 10 weeks. The study aims to provide insights into whether Troriluzole can be an effective addition to existing OCD treatments, potentially offering a new option for those who have not found relief with their current medication regimen.

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 assessment

    The study begins with an initial assessment to confirm the primary diagnosis of Obsessive Compulsive Disorder (OCD). This is done using a structured interview called the MINI.

    The duration of the illness must be at least one year. The assessment also checks if there is a non-response or inadequate response to current medication, with a Y-BOCS score of 22 or higher, indicating moderate or severe symptoms.

  2. Step 2

    Eligibility confirmation

    Eligibility is confirmed by ensuring the patient is currently on a specific type of medication, such as an SSRI (excluding fluvoxamine), clomipramine, venlafaxine, or desvenlafaxine, at an adequate dose and duration.

  3. Step 3

    Randomization and treatment

    Participants are randomly assigned to receive either troriluzole or a placebo. Troriluzole is administered in capsule form, taken orally.

    The dosage and frequency of administration are determined by the study protocol, and participants continue their current OCD medication alongside the study treatment.

  4. Step 4

    Monitoring and evaluation

    Throughout the trial, participants are regularly monitored to assess the improvement in OCD symptoms. This is primarily measured by the change in the Y-BOCS score from the baseline.

    Secondary assessments include changes in the SDS total score and the CGI Severity score.

  5. Step 5

    Completion and follow-up

    The trial is estimated to conclude by June 13, 2025. Upon completion, participants may undergo a final evaluation to assess the overall impact of the treatment.

Who can join the trial?

7 criteria

  • The patient must have a primary diagnosis of Obsessive Compulsive Disorder (OCD), which is a mental health condition characterized by unwanted and repeated thoughts, feelings, ideas, or sensations (obsessions) that drive them to do something repetitively (compulsions).
  • The patient must have had OCD for at least 1 year.
  • The patient must currently be experiencing a non-response or inadequate response to their current treatment for OCD. This means their symptoms are not improving enough with their current medication.
  • The patient's Y-BOCS score, which is a scale used to measure the severity of OCD symptoms, must be 22 or higher at the start of the study, indicating moderate or severe symptoms.
  • The patient must be taking one of the following medications: an SSRI (a type of antidepressant), clomipramine, venlafaxine, or desvenlafaxine. These medications should be taken for a sufficient amount of time and at the right dose as specified in the study protocol.
  • The study is open to both male and female patients.
  • The study includes patients who are considered part of a vulnerable population, which means they may need special protection or consideration.

Who cannot join the trial?

9 criteria

  • Individuals who do not have Obsessive Compulsive Disorder (OCD) cannot participate. OCD is a condition where a person has unwanted thoughts and feels the need to perform certain actions repeatedly.
  • Participants must be within a specific age range, typically adults and older teenagers. Younger children and older adults may not be eligible.
  • Both males and females can participate, but certain health conditions specific to gender may exclude someone.
  • People who are considered part of a vulnerable population may not be eligible. This can include individuals who might have difficulty understanding the study or making decisions about their participation.
  • Participants must have had an inadequate response to their current OCD treatment. This means their current treatment isn't working well enough.
  • Individuals with certain other medical conditions or who are taking specific medications might be excluded to ensure safety.
  • Pregnant or breastfeeding women are often excluded to protect the health of the mother and baby.
  • People with a history of certain mental health conditions or substance abuse might not be eligible.
  • Participants must be able to comply with the study requirements, such as attending appointments and taking medication as directed.
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Investigated drugs

Troriluzole is being studied as an additional treatment for people with Obsessive Compulsive Disorder (OCD) who have not responded well to their current OCD medications. The goal is to see if adding troriluzole can help improve symptoms of OCD, as measured by a specific scale used to assess the severity of OCD symptoms.

What is already known about the treatment

Troriluzole – Troriluzole is administered orally and is currently being studied in clinical trials as an adjunctive treatment for Obsessive Compulsive Disorder (OCD). It is not yet widely established in medical practice, as research is ongoing to determine its effectiveness. The main therapeutic indication for Troriluzole is to help manage symptoms of OCD, particularly in patients who have not responded adequately to existing treatments. At the molecular level, Troriluzole is believed to modulate glutamate levels in the brain, which may help reduce OCD symptoms. It is classified pharmacologically as a glutamate modulator.

Investigated diseases

Obsessive Compulsive Disorder – Obsessive Compulsive Disorder (OCD) is a mental health condition characterized by persistent, unwanted thoughts (obsessions) and repetitive behaviors or mental acts (compulsions) that an individual feels driven to perform. These obsessions and compulsions can significantly interfere with daily activities and social interactions. The obsessions often cause significant anxiety or distress, leading the person to engage in compulsions as a way to reduce this discomfort. Over time, the compulsions may become more time-consuming and distressing, further impacting the individual's quality of life. The disorder can vary in severity, with some individuals experiencing mild symptoms, while others may have severe and debilitating symptoms.
Trial detailsLast updated 7 Oct 2026
Age18+ yearsPhasePhase IIITrial ID2024-514585-39-00Protocol codeBHV4157-303Estimated enrolment700 patientsSponsorBiohaven Pharmaceuticals Inc.

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