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Study of daridorexant and buprenorphine combination treatment for patients with opioid use 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 focuses on treating patients with Opioid Use Disorder (OUD), a condition where a person becomes dependent on opioid substances. The study will test whether adding daridorexant, a sleep medication, can help improve the effectiveness of standard OUD treatment with buprenorphine. Buprenorphine is a medication commonly used to treat opioid dependence.

The study aims to determine if daridorexant can help reduce the use of illegal substances in patients who are receiving buprenorphine treatment. During the study, participants will receive either daridorexant or placebo while continuing their regular buprenorphine treatment. The buprenorphine will be given as an injection under the skin or as tablets that dissolve under the tongue.

The treatment period will last for several months, during which participants will regularly provide urine samples and complete questionnaires about their sleep quality, drug cravings, and overall well-being. The study will monitor how well participants respond to the combined treatment approach and whether it helps them maintain their recovery from opioid use disorder.

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 and medication start

    After confirming your eligibility and obtaining your consent, you will start receiving buprenorphine treatment.

    If you are not currently on buprenorphine treatment, you will first be stabilized using sublingual tablets (placed under the tongue).

    Once stabilized, you will receive depot buprenorphine through subcutaneous injection (under the skin).

  2. Step 2

    Study medication phase

    You will receive either daridorexant tablets or placebo tablets to take by mouth.

    The study will last for 13 weeks.

    You will need to take the assigned medication as prescribed throughout the study period.

  3. Step 3

    Weekly assessments

    Each week, you will need to provide a urine sample for testing.

    You will complete several questionnaires about:

    - Your cravings for opioids

    - Any withdrawal symptoms you may experience

    - Your sleep quality

    You will report your substance use through a timeline follow-back method.

  4. Step 4

    Monthly assessments

    Once per month, you will complete additional questionnaires about:

    - The severity of substance-related issues

    - Your sleep problems

    - Your daily functioning and activities

  5. Step 5

    Study completion

    The study will conclude after the 13-week period.

    Your participation will help evaluate if daridorexant can reduce substance use when added to buprenorphine treatment.

Who can join the trial?

8 criteria

  • Age between 20 and 65 years old (men and women)
  • Must have moderate-to-severe opioid use disorder (a condition involving problematic opioid use) for at least 1 year, confirmed by a healthcare professional
  • Can be either:
    • Currently not in stable recovery from opioid use
    • In stable recovery but still using other substances
    • Eligible if:
      • Not currently receiving opioid maintenance treatment
      • Currently receiving buprenorphine treatment (a medication used to treat opioid dependence) taken under the tongue or inside the cheek
      • Must be able to speak and read Swedish
      • Must be willing to provide informed consent (agreement to participate after understanding study details)

Who cannot join the trial?

14 criteria

  • Current diagnosis of severe mental health conditions (such as schizophrenia, bipolar disorder, or severe depression)
  • History of seizures or epilepsy
  • Pregnant women or those planning pregnancy during the study period
  • Current severe liver disease (problems with liver function)
  • Use of medications that could interact with the study drug
  • Participation in another clinical trial within the past 30 days
  • Unable to follow study procedures or attend scheduled visits
  • History of allergic reactions to similar medications
  • Unstable medical conditions that could interfere with the study
  • Sleep apnea (a condition where breathing repeatedly stops during sleep) that is not properly treated
  • Current use of other sleep medications that cannot be discontinued
  • History of substance abuse other than opioids in the past 30 days
  • Severe breathing problems or respiratory conditions
  • Inability to provide informed consent
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Investigated drugs

  • Daridorexant

    is a medication that works by blocking orexin receptors in the brain. It is being studied as a potential treatment to help people who are dealing with opioid use disorder. This medication affects sleep-wake cycles and may help reduce cravings for illicit substances.

  • Buprenorphine

    is a well-established medication used to treat opioid dependence. It helps reduce withdrawal symptoms and cravings in people who are recovering from opioid use disorder. In this trial, it is used in a long-acting depot form, which means it is given as an injection that releases the medication slowly over time.

What is already known about the treatment

  • Daridorexant

    A dual orexin receptor antagonist administered orally that works by blocking both orexin receptors in the brain, helping to regulate sleep-wake cycles. This medication is currently being investigated as a potential adjunct therapy for patients with Opioid Use Disorder who are undergoing buprenorphine maintenance treatment. It belongs to the pharmacological class of orexin receptor antagonists and represents a novel approach to addressing substance use disorders by targeting sleep regulation pathways.

  • Buprenorphine

    A partial opioid agonist medication administered via long-acting depot injection that helps manage Opioid Use Disorder by binding to opioid receptors in the brain. This FDA-approved medication reduces cravings and withdrawal symptoms while preventing the full effects of other opioids, making it a cornerstone of medication-assisted treatment for opioid dependence. As a maintenance therapy, it helps patients achieve stability and supports their recovery process while having a lower risk of respiratory depression compared to full opioid agonists.

Investigated diseases

Opioid Use Disorder - A chronic medical condition characterized by a problematic pattern of opioid use that causes significant impairment in daily life. The disorder develops when a person becomes physically and psychologically dependent on opioids, whether prescription pain medications or illegal substances. People with this condition experience strong urges to use opioids and may need increasing amounts to achieve the desired effect. The disorder often involves difficulties controlling opioid use, continued use despite problems in relationships or responsibilities, and the development of tolerance. Physical and emotional changes occur, including sleep disturbances and mood fluctuations when opioids are not taken.
Trial detailsLast updated 7 Oct 2026
Age18+ yearsPhasePhase IITrial ID2024-517482-16-00Protocol codeBUDAEstimated enrolment192 patientsSponsorLinkopings Universitet

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