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Study on the Effects of NMRA-335140 for Adults with Major Depressive Disorder

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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 the effects of a new treatment for Major Depressive Disorder (MDD), a condition characterized by persistent feelings of sadness and loss of interest. The treatment being tested is a medication called NMRA-335140, which is taken orally in the form of a film-coated tablet. This medication is a type of drug known as a kappa opioid receptor antagonist, which means it works by blocking certain receptors in the brain that are thought to be involved in depression.

The purpose of the study is to evaluate how effective NMRA-335140 is in reducing symptoms of depression compared to a placebo. Participants in the study will be randomly assigned to receive either NMRA-335140 or a placebo, which looks like the active medication but does not contain the active drug substance. The study will last for six weeks, during which participants will take the medication daily. Throughout the study, participants will be monitored to assess changes in their symptoms of depression.

This trial aims to provide valuable information about the potential benefits of NMRA-335140 for individuals with Major Depressive Disorder. By comparing the effects of the medication to a placebo, researchers hope to determine whether NMRA-335140 can offer a new treatment option for those affected by this condition.

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

    Joining the study

    Upon joining the study, the participant is confirmed to have a primary diagnosis of major depressive disorder (MDD) without psychotic features. This is verified through a structured clinical interview.

    The current episode of depression must have been present for more than 4 weeks but less than 12 months before the screening visit.

  2. Step 2

    Baseline assessment

    The participant's symptoms are assessed using the Montgomery-Åsberg Depression Rating Scale (MADRS). A total score of 25 or higher is required at both screening and baseline.

    A change in the MADRS total score between screening and baseline must be 20% or less.

  3. Step 3

    Randomization and treatment

    Participants are randomly assigned to receive either the active medication NMRA-335140 or a placebo. The study is double-blind, meaning neither the participant nor the researchers know which treatment is being administered.

    The active medication, NMRA-335140, is a kappa opioid receptor antagonist. It is administered orally in the form of a film-coated tablet.

    The dosage is 80 mg per day, and the treatment period lasts for 6 weeks.

  4. Step 4

    Treatment evaluation

    The primary goal is to evaluate the change in the MADRS total score from baseline to week 6.

    A secondary evaluation involves assessing changes in the Snaith-Hamilton Pleasure Scale (SHAPS) total score over the same period.

  5. Step 5

    Completion of the study

    The study is estimated to conclude by June 2, 2025. Participants will have completed the 6-week treatment period by this time.

Who can join the trial?

6 criteria

  • The patient must have a primary diagnosis of Major Depressive Disorder (MDD) without psychotic features. This diagnosis should be confirmed by a structured interview used in clinical trials.
  • The patient's current major depressive episode must be confirmed by an independent assessment.
  • The symptoms of the current MDD episode must have been present for more than 4 weeks but no longer than 12 months before the screening visit.
  • The patient must have a MADRS total score of 25 or higher at both the screening and baseline visits. MADRS stands for Montgomery-Åsberg Depression Rating Scale, which is a tool used to measure the severity of depression symptoms.
  • The change in the MADRS total score between the screening and baseline visits must be 20% or less.
  • Both male and female patients are eligible to participate.

Who cannot join the trial?

8 criteria

  • Patients who have a different condition than Major Depressive Disorder cannot participate. This means if you have another mental health condition, you may not be eligible.
  • Patients who are not within the specified age range for the study cannot participate. The study is looking for adults, so if you are too young or too old, you may not be eligible.
  • Patients who are not able to follow the study procedures or take the study medication as required cannot participate. This means if you have difficulty following instructions or taking medication regularly, you may not be eligible.
  • Patients who have a medical condition that could interfere with the study medication or its effects cannot participate. This means if you have a health issue that might affect how the study drug works, you may not be eligible.
  • Patients who are pregnant or breastfeeding cannot participate. This is to ensure the safety of both the mother and the baby.
  • Patients who are currently participating in another clinical trial cannot participate. This is to avoid any interference between different study treatments.
  • Patients who have a history of substance abuse or addiction that could interfere with the study cannot participate. This means if you have had problems with drugs or alcohol that might affect the study, you may not be eligible.
  • Patients who have had a recent major surgery or are planning to have surgery during the study cannot participate. This is to ensure that recovery from surgery does not affect the study results.
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Investigated drugs

NMRA-335140 is a medication being studied for its potential effects on major depressive disorder. It works as a kappa opioid receptor antagonist, which means it blocks certain receptors in the brain that may be involved in mood regulation. The trial aims to determine if this medication can help reduce symptoms of depression in adults with major depressive disorder after six weeks of treatment.

What is already known about the treatment

NMRA-335140 – This medication is administered orally and is currently being studied in clinical trials for its potential use in treating Major Depressive Disorder. It is a kappa opioid receptor antagonist, which means it works by blocking specific receptors in the brain that are thought to be involved in mood regulation. The main therapeutic indication for NMRA-335140 is to alleviate symptoms of depression. As a kappa opioid receptor antagonist, it falls under the pharmacological classification of opioid receptor antagonists.

Investigated diseases

Major Depressive Disorder – This is a mental health condition characterized by persistent feelings of sadness, hopelessness, and a lack of interest or pleasure in activities. It can affect a person's thoughts, behavior, and overall well-being. Symptoms may include changes in appetite, sleep disturbances, fatigue, and difficulty concentrating. The disorder can vary in severity and duration, with some individuals experiencing recurrent episodes. It often interferes with daily functioning and can lead to emotional and physical problems. The progression of the disorder can differ from person to person, with some experiencing gradual improvement while others may have persistent symptoms.
Trial detailsLast updated 7 Oct 2026
Age18+ yearsPhasePhase IIITrial ID2023-506335-15-00Protocol codeNMRA-335140-303Estimated enrolment332 patientsSponsorNeumora Therapeutics Inc.

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