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Study on Seltorexant for Adults and Elderly with Major Depressive Disorder and Insomnia Symptoms

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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 medication called seltorexant on adults and elderly patients who have Major Depressive Disorder with symptoms of insomnia. Major Depressive Disorder, often referred to as depression, is a condition characterized by persistent feelings of sadness and loss of interest, which can significantly impact daily life. Insomnia is a common symptom of depression, where individuals have trouble falling or staying asleep.

The purpose of the study is to evaluate how well seltorexant works when used alongside other antidepressants, specifically those known as SSRIs (Selective Serotonin Reuptake Inhibitors) or SNRIs (Serotonin-Norepinephrine Reuptake Inhibitors). The study will compare the effects of taking seltorexant with a placebo, which looks like the medication but does not contain the active ingredient. The study aims to see if seltorexant can improve depressive symptoms and help maintain these improvements over time.

Participants in the study will take part in two main parts. In the first part, the effectiveness of seltorexant in improving symptoms of depression will be assessed. In the second part, the focus will be on whether seltorexant can help prevent the return of depressive symptoms after initial improvement. The study will involve taking the medication in the form of a film-coated tablet by mouth. The trial is designed to ensure the safety and effectiveness of seltorexant as an additional treatment for those who have not fully responded to their current antidepressant therapy.

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

    An initial assessment is conducted to confirm eligibility. This includes a physical examination, checking vital signs, and performing an ECG (a test that measures the electrical activity of the heart).

    Eligibility is based on criteria such as age (18 to 74 years), a diagnosis of major depressive disorder with insomnia symptoms, and an inadequate response to certain antidepressants.

  2. Step 2

    Part 1: treatment phase

    Participants receive either seltorexant 20 mg or a placebo as an additional treatment to their current antidepressant. The medication is taken orally in the form of a film-coated tablet.

    The goal is to assess the effectiveness of seltorexant in improving depressive symptoms over a period of 43 days.

  3. Step 3

    Evaluation of response

    The change in depressive symptoms is measured using the MADRS (Montgomery-Åsberg Depression Rating Scale) from the start of the treatment to Day 43.

    Participants who show a stable response to the treatment may proceed to the next phase.

  4. Step 4

    Part 2: maintenance phase

    Participants who have a stable response enter a double-blind maintenance phase. This phase aims to evaluate the ability of seltorexant to delay the relapse of depressive symptoms.

    The time from randomization to the first relapse is monitored during this phase.

  5. Step 5

    Completion of trial

    The trial is estimated to conclude by December 30, 2026.

    Participants' progress and any changes in symptoms are continuously monitored throughout the trial duration.

Who can join the trial?

9 criteria

  • Participants must be between 18 and 74 years old.
  • Participants should be in good health based on a physical exam, vital signs check, and heart test (12-lead ECG) done at the start of the study.
  • Participants must meet the DSM-5 criteria for Major Depressive Disorder (MDD) without any psychotic features. DSM-5 is a guide used by doctors to diagnose mental health conditions.
  • Participants should have tried at least one but not more than two antidepressants during their current depression episode, but these did not work well enough. The antidepressant should have been taken for at least 6 weeks at a stable dose.
  • Participants must be taking and handling well one of the following antidepressants: citalopram, duloxetine, escitalopram, fluvoxamine, fluoxetine, milnacipran, levomilnacipran, paroxetine, sertraline, venlafaxine, desvenlafaxine, vilazodone, or vortioxetine. The dose should be stable and at a therapeutic level for at least 6 weeks.
  • Participants should be experiencing a major depressive episode that is at least moderately severe, as measured by a specific depression scale (SIGH-D) during the screening. There should not be a significant improvement in symptoms from the start to the end of the screening.
  • Participants should have a Body Mass Index (BMI) between 18 and 40 kg/m². BMI is a measure of body fat based on height and weight.
  • Participants who are continuing from Part 1 of the study must have completed the treatment phase of Part 1.
  • Participants must be able to consistently tolerate the study medication.

Who cannot join the trial?

5 criteria

  • Participants who have a medical condition other than **Major Depressive Disorder with Insomnia Symptoms**.
  • Participants who have not had an inadequate response to their current **SSRI/SNRI antidepressant therapy**. **SSRI** and **SNRI** are types of medications used to treat depression.
  • Participants who are not within the specified age range for the study.
  • Participants who are not able to follow the study procedures or take the study medication as required.
  • Participants who are part of a vulnerable population that the study is not designed to include.
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Investigated drugs

Seltorexant is a medication being studied for its potential to help people with major depressive disorder who also have trouble sleeping. It is used in combination with other antidepressants, specifically SSRIs or SNRIs, to see if it can improve symptoms of depression in those who haven't responded well to their current treatment. The study is also looking at whether Seltorexant can help prevent the return of depressive symptoms after initial improvement.

What is already known about the treatment

Seltorexant – Seltorexant is administered orally in tablet form and is currently being studied in clinical trials as an adjunctive therapy for adults and elderly patients with Major Depressive Disorder with Insomnia Symptoms. It is not yet widely available in medical practice, as it is still under investigation. The main therapeutic indication for seltorexant is to improve depressive symptoms and delay relapse in patients who have not responded adequately to standard antidepressant treatments. At the molecular level, seltorexant works by selectively antagonizing the orexin-2 receptor, which is believed to play a role in regulating mood and sleep. It is classified pharmacologically as an orexin receptor antagonist.

Investigated diseases

Major Depressive Disorder with Insomnia Symptoms – This condition is characterized by persistent feelings of sadness, hopelessness, and a lack of interest or pleasure in activities, accompanied by difficulties in falling or staying asleep. Individuals may experience changes in appetite, energy levels, and concentration. The insomnia symptoms can exacerbate the depressive symptoms, creating a cycle that can be challenging to break. Over time, the lack of restful sleep can lead to increased irritability and difficulty in managing daily tasks. The disorder can vary in intensity and duration, with some individuals experiencing more severe symptoms than others.
Trial detailsLast updated 7 Oct 2026
Age18+ yearsPhasePhase IIITrial ID2023-509070-36-00Protocol code42847922MDD3003Estimated enrolment724 patientsSponsorJanssen Cilag International

sourced from the EU Clinical Trials Register and site verification

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