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Study on the Safety and Effectiveness of AMX0035 (Phenylbutyrate and Ursodoxicoltaurine) for Adults with Amyotrophic Lateral Sclerosis (ALS)

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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 Amyotrophic Lateral Sclerosis (ALS), a progressive disease that affects nerve cells in the brain and spinal cord, leading to muscle weakness and loss of movement. The trial will evaluate the safety and effectiveness of a treatment called AMX0035, which is a combination of two substances: phenylbutyrate and ursodoxicoltaurine. These substances are provided in a powder form and taken orally. The study will compare the effects of AMX0035 to a placebo over a period of 48 weeks.

The purpose of the study is to assess how AMX0035 impacts the progression of ALS in adult patients. Participants will be randomly assigned to receive either AMX0035 or a placebo, and neither the participants nor the researchers will know who is receiving which treatment. This is known as a double-blind study. Throughout the 48 weeks, participants will have regular visits to the clinic to monitor their health and the progression of the disease.

During the trial, researchers will measure changes in the participants' abilities to perform daily activities and their overall survival. The study aims to provide valuable information on whether AMX0035 can slow down the progression of ALS and improve the quality of life for those affected by this challenging 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 participant will be informed about the trial's purpose, procedures, and requirements. The participant must provide informed consent, confirming understanding and willingness to comply with the trial procedures.

  2. Step 2

    Baseline assessment

    A baseline assessment will be conducted to evaluate the participant's current health status and ALS condition. This includes measuring the ALS Functional Rating Scale-Revised (ALSFRS-R) score, which assesses the participant's physical function.

  3. Step 3

    Treatment phase

    The participant will receive the study medication, AMX0035, or a placebo. AMX0035 is an oral powder containing phenylbutyrate and ursodoxicoltaurine, taken by mouth. The treatment will last for 48 weeks.

    The participant will take the medication as directed, following the dosage and frequency specified by the study protocol.

  4. Step 4

    Regular assessments

    Throughout the 48-week treatment period, the participant will attend regular clinic visits and remote assessments. These visits will monitor the participant's health, ALS progression, and any side effects from the medication.

    The ALSFRS-R score will be reassessed at various intervals, including at Week 24 and Week 48, to track changes in physical function.

  5. Step 5

    End of treatment evaluation

    At the end of the 48-week treatment period, a final evaluation will be conducted. This includes a comprehensive assessment of the participant's ALS condition and overall health.

    The primary endpoint is the change in the ALSFRS-R total score from baseline to Week 48, adjusted for mortality.

  6. Step 6

    Follow-up period

    After completing the treatment phase, the participant will enter a follow-up period. This involves continued monitoring of health status and any long-term effects of the treatment.

    Participants are required to adhere to birth control measures for 3 months after the last dose of the study drug.

Who can join the trial?

10 criteria

  • Must be a male or female who is at least 18 years old.
  • Men should not plan to father a child or donate sperm during the trial and for 3 months after the last dose of the study drug.
  • Must have a diagnosis of Amyotrophic Lateral Sclerosis (ALS), confirmed by a doctor experienced in ALS management.
  • The first symptom of ALS should have started less than 24 months ago.
  • If taking medications like riluzole or edaravone, these should have been started and kept stable for at least 14 days for riluzole or a full treatment cycle for edaravone before the trial begins.
  • Must be able to give informed consent, which means understanding and agreeing to participate in the trial.
  • Must be capable and willing to follow trial procedures, including attending clinic visits, remote visits, and reporting status as required.
  • Women who can have children must agree to use effective birth control during the trial and for 3 months after the last dose of the study drug.
  • Women must not be pregnant or planning to become pregnant during the trial and for 3 months after the last dose of the study drug.
  • Men must agree to use contraception during the trial and for at least 3 months after the last dose of the study drug.

Who cannot join the trial?

10 criteria

  • Patients who have a medical condition other than Amyotrophic Lateral Sclerosis (ALS) that could interfere with the study.
  • Patients who are unable to follow the study procedures or attend the required visits.
  • Patients who are currently participating in another clinical trial.
  • Patients who have a history of allergic reactions to the study medication or similar drugs.
  • Patients who have a serious illness or condition that could affect their safety during the study.
  • Patients who are pregnant or breastfeeding.
  • Patients who have a history of drug or alcohol abuse that could interfere with the study.
  • Patients who have had a recent major surgery or are planning to have surgery during the study period.
  • Patients who have a mental health condition that could affect their ability to participate in the study.
  • Patients who are unable to provide informed consent, which means they cannot understand and agree to the study's requirements.
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Investigated drugs

AMX0035 is a medication being studied for its potential to slow down the progression of Amyotrophic Lateral Sclerosis (ALS) in adults. ALS is a disease that affects nerve cells in the brain and spinal cord, leading to loss of muscle control. This trial aims to evaluate the safety and effectiveness of AMX0035 over a 48-week period.

What is already known about the treatment

AMX0035 – This medication is administered orally and is currently being studied in clinical trials for its potential benefits in treating Amyotrophic Lateral Sclerosis (ALS). It is in the experimental phase, with ongoing research to evaluate its safety and effectiveness. The main therapeutic indication for AMX0035 is to slow the progression of ALS, a neurodegenerative disease. At the molecular level, AMX0035 is believed to work by protecting nerve cells from damage and death, although the exact mechanism is still under investigation. It falls under the pharmacological classification of neuroprotective agents.

Investigated diseases

Amyotrophic Lateral Sclerosis (ALS) – ALS is a progressive neurodegenerative disease that affects nerve cells in the brain and spinal cord. It leads to the gradual degeneration and death of motor neurons, which are responsible for controlling voluntary muscles. As these neurons die, the brain loses the ability to initiate and control muscle movement, leading to muscle weakness and atrophy. Over time, individuals with ALS may experience difficulty speaking, swallowing, and breathing. The progression of the disease varies among individuals, but it typically leads to increasing disability. ALS is considered a rare disease and its exact cause is not fully understood.
Trial detailsLast updated 2 Oct 2026
Age18+ yearsPhasePhase IIITrial ID2023-508511-23-00Protocol codeA35-004Estimated enrolment664 patientsSponsorAmylyx Pharmaceuticals Inc.

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