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Study on the Effectiveness and Safety of Dexamfetamine Sulfate for Adults with ADHD

Verified siteRegistered drugNo placebo
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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 effectiveness and safety of two different formulations of dexamfetamine sulfate in adults diagnosed with Attention Deficit Hyperactivity Disorder (ADHD). The study will compare immediate-release tablets and modified-release capsules of dexamfetamine sulfate with a placebo. The purpose of the study is to determine how well these medications work in managing symptoms of ADHD in adults.

Participants in the study will be randomly assigned to receive either the immediate-release tablets, the modified-release capsules, or a placebo. The study will be conducted in a way that neither the participants nor the researchers know which treatment is being given, ensuring unbiased results. The trial will last for a period of 44 weeks, during which participants will take the medication orally. The study aims to observe changes in ADHD symptoms over time and assess any side effects that may occur.

The trial will involve regular visits to monitor the participants' progress and gather data on the effectiveness of the treatments. By the end of the study, researchers hope to gain valuable insights into the potential benefits of using dexamfetamine sulfate formulations for treating ADHD in adults. This information could help improve treatment options for individuals living with this condition.

The research process

The trial runs in 6 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 patient will be randomly assigned to one of the treatment groups. This process ensures that each participant has an equal chance of receiving any of the treatments being tested.

  2. Step 2

    Treatment phase

    The patient will receive one of the following treatments: immediate-release dexamfetamine sulfate (DEX IR) tablets, modified-release dexamfetamine sulfate (DEX XL) capsules, or a placebo. The placebo is a substance with no active medication, used to compare the effects of the actual drugs.

    The DEX IR tablets are taken orally. The dosage and frequency will be determined by the study protocol.

    The DEX XL capsules are also taken orally. These capsules release the medication over a longer period, and the dosage and frequency will be specified in the study protocol.

  3. Step 3

    Optimal stable dose phase

    During this phase, the patient will continue taking the assigned medication. The goal is to find the optimal dose that provides the best balance between effectiveness and side effects.

    The patient's response to the medication will be monitored, and adjustments to the dosage may be made as needed.

  4. Step 4

    Evaluation of treatment effectiveness

    The effectiveness of the treatment will be evaluated by measuring changes in specific scores, such as the ADHS-DC-Q and SDS scores, from the start of the study to the end of the optimal stable dose phase.

    These scores help assess the impact of the medication on the patient's symptoms and overall functioning.

  5. Step 5

    Long-term follow-up or withdrawal phase

    In this phase, the patient may continue with the treatment or begin a withdrawal process, depending on the study design.

    The patient's progress will be monitored to evaluate any changes in symptoms or side effects during this period.

  6. Step 6

    End of treatment

    At the end of the study, the patient's overall response to the treatment will be assessed.

    Final evaluations will be conducted to determine the effectiveness and safety of the medication compared to the placebo.

Who can join the trial?

6 criteria

  • The patient must sign a form agreeing to participate and allowing the use of their data before any trial activities begin.
  • The patient must be an adult, either male or female, who is at least 18 years old at the time they join the study.
  • The patient must have a diagnosis of ADHD (Attention Deficit/Hyperactivity Disorder) based on a detailed psychiatric evaluation using a special interview tool. This tool could be the Wender-Reimherr Adult Attention Deficit Disorder Scale (WRAADDS) or a similar one. This applies to patients who have not been diagnosed before or those diagnosed more than 12 months ago.
  • The patient must have proof that their ADHD started in childhood, before the age of 12, using a questionnaire called the WURS-k for looking back at past symptoms.
  • The patient must have a minimum score of 32 on the ADHS-DC-Q test during the initial screening visit.
  • The patient must have a minimum score of 4 on the CGI-S test during the initial screening visit. The CGI-S is a tool used to rate the severity of the patient's condition.

Who cannot join the trial?

3 criteria

  • Patients who do not have a diagnosis of ADHD (Attention Deficit Hyperactivity Disorder) according to specific guidelines.
  • Patients who are not adults, as the study is for adult patients only.
  • Patients who are part of a vulnerable population, which means they might need special protection or care.
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Investigated drugs

  • Dexamfetamine Sulfate Immediate-Release (DEX IR)

    is a medication used in this trial to help manage symptoms of ADHD in adults. It works by affecting certain chemicals in the brain that contribute to hyperactivity and impulse control. This formulation is designed to release the medication quickly after ingestion, providing a rapid onset of effects.

  • Dexamfetamine Sulfate Modified-Release (DEX XL)

    is another formulation of the same medication used in the trial. This version is designed to release the medication more slowly over time, which can help maintain its effects throughout the day. This can be beneficial for individuals who need longer-lasting symptom control.

What is already known about the treatment

  • Dexamfetamine Sulfate (DEX IR)

    This medication is administered orally in the form of immediate-release tablets. It is currently being studied in clinical trials to assess its effectiveness and safety for treating adults with Attention Deficit Hyperactivity Disorder (ADHD). The main therapeutic indication is for managing symptoms of ADHD. At the molecular level, dexamfetamine works by increasing the levels of certain neurotransmitters in the brain, such as dopamine and norepinephrine, which help improve attention and focus. It is classified as a central nervous system stimulant.

  • Dexamfetamine Sulfate (DEX XL)

    This medication is administered orally in the form of modified-release capsules. It is under investigation in clinical trials to determine its efficacy and safety for adults with ADHD. The primary therapeutic use is to alleviate symptoms associated with ADHD. The mechanism of action involves enhancing the activity of neurotransmitters like dopamine and norepinephrine in the brain, which aids in improving concentration and reducing impulsivity. It belongs to the pharmacological class of central nervous system stimulants.

Investigated diseases

Attention Deficit Hyperactivity Disorder (ADHD) – ADHD is a neurodevelopmental disorder characterized by a persistent pattern of inattention and/or hyperactivity-impulsivity that interferes with functioning or development. Symptoms of inattention may include difficulty sustaining attention, not following through on tasks, and being easily distracted. Hyperactivity-impulsivity symptoms can manifest as fidgeting, excessive talking, or an inability to wait one's turn. The disorder often begins in childhood and can continue into adulthood, affecting various aspects of life such as work, education, and relationships. The severity and specific symptoms can vary widely among individuals, and they may change over time.
Trial detailsLast updated 2 Oct 2026
Age18+ yearsPhasePhase IIITrial ID2022-502903-31-00Protocol code6520-9970-08Estimated enrolment380 patientsSponsorMEDICE Arzneimittel Puetter GmbH & Co. KG

sourced from the EU Clinical Trials Register and site verification

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On this site, “treatment” means an investigational medicine being studied in a clinical trial. Its safety and efficacy for the use being studied have not yet been confirmed, some participants may receive a placebo or a comparator medicine, and taking part does not guarantee any health benefit. The decision to take part is made by the doctor at the research site. This site is for information only and does not replace medical advice.

This service is not affiliated with the European Commission, the EMA, or the official CTIS system. Most information comes from publicly available international clinical-trial registries, supplemented by data from academic sites, national regulators and commercial sponsors. On this site, “treatment” and “therapy” mean a medicine being tested in a clinical trial. Its safety and effectiveness in the use being studied are not yet confirmed, some participants may receive a placebo or a comparator, and taking part does not guarantee a health benefit. The doctor at the research site decides who can take part. This site provides information, not medical advice. Certain content and visual elements on this website have been generated or enhanced using artificial intelligence (AI).