for people ages 18-80 (full criteria)
at Orange, California and other locations
study started
estimated completion



The CENTAUR trial will be a 2:1 (active:placebo) randomized, double-blind, placebo-controlled Phase II trial to evaluate the safety and efficacy of AMX0035 for the treatment of ALS.

Official Title

Evaluation of the Safety, Tolerability, Efficacy and Activity of AMX0035, a Fixed Combination of Phenylbutyrate (PB) and Tauroursodeoxycholic Acid (TUDCA), for the Treatment of ALS


AMX0035 is a combination therapy designed to reduce neuronal death through blockade of key cellular death pathways originating in the mitochondria and endoplasmic reticulum (ER). This clinical trial is designed to demonstrate that treatment is safe, tolerable, and able to slow decline in function as measured by the ALSFRS-R. The trial will also assess the effects of AMX0035 on muscle strength, vital capacity, and biomarkers of ALS including markers of neuronal death and neuroinflammation.


Amyotrophic Lateral Sclerosis Motor Neuron Disease Neuromuscular Diseases Neurodegenerative Diseases Spinal Cord Diseases TDP-43 Proteinopathies Nervous System Diseases Central Nervous System Diseases Randomized Double-blind Placebo-controlled Sodium Phenylbutyrate Tauroursodeoxycholic Acid Sclerosis 4-phenylbutyric acid Taurochenodeoxycholic Acid AMX0035


For people ages 18-80

Key Inclusion Criteria:

  1. Male or female, aged 18-80 years of age
  2. Sporadic or familial ALS diagnosed as definite as defined by the World Federation of Neurology revised El Escorial criteria
  3. Less than or equal to 18 months since ALS symptom onset
  4. Capable of providing informed consent and following trial procedures
  5. Slow Vital Capacity (SVC) >60% of predicted value for gender, height, and age at the Screening Visit
  6. Subjects must either not take riluzole or be on a stable dose of riluzole for at least 30 days prior to the Screening Visit. Riluzole-naïve subjects are permitted in the study.
  7. Women of child bearing potential (e.g. not post-menopausal for at least one year or surgically sterile) must agree to use adequate birth control for the duration of the study and 3 months after last dose of study drug. Women must not be planning to become pregnant for the duration of the study and 3 months after last dose of study drug
  8. Men must agree to practice contraception for the duration of the study and 3 months after last dose of study drug. Men must not plan to father a child or provide for sperm donation for the duration of the study and 3 months after last dose of study drug

Key Exclusion Criteria:

  1. Presence of tracheostomy
  2. Exposure to PB, TUDCA or UDCA within 3 months prior to the Screening Visit or planning to use these medications during the course of the study
  3. History of known allergy to PB or bile salts
  4. Abnormal liver function defined as AST and/or ALT > 3 times the upper limit of the normal
  5. Renal insufficiency as defined by a serum creatinine > 1.5 times the upper limit of normal
  6. Poorly controlled arterial hypertension (SBP>160mmHg or DBP>100mmHg) at the Screening Visit
  7. Pregnant women or women currently breastfeeding
  8. History of cholecystectomy
  9. Biliary disease which impedes biliary flow including active cholecystitis, primary biliary cirrhosis, sclerosing cholangitis, gallbladder cancer, gallbladder polyps, gangrene of the gallbladder, abscess of the gallbladder.
  10. . History of Class III/IV heart failure (per New York Heart Association - NYHA)
  11. . Severe pancreatic or intestinal disorders that may alter the enterohepatic circulation and absorption of TUDCA including biliary infections, pancreatitis and ileal resection
  12. . The presence of unstable psychiatric disease, cognitive impairment, dementia or substance abuse that would impair ability of the subject to provide informed consent, according to Site Investigator judgment
  13. . Clinically significant unstable medical condition (other than ALS) that would pose a risk to the subject if they were to participate in the study
  14. . Active participation in an ALS clinical trial evaluating a small molecule within 30 days of the Screening Visit
  15. . Exposure at any time to any biologic under investigation for the treatment of subjects with ALS (off-label use or investigational) including cell therapies, gene therapies, and monoclonal antibodies.
  16. . Implantation of Diaphragm Pacing System (DPS)


  • UC Irvine Medical Center
    Orange California 92868 United States
  • Barrow Neurological Institute
    Phoenix Arizona 85013 United States


in progress, not accepting new patients
Start Date
Completion Date
Amylyx Pharmaceuticals Inc.
TUDCA in patients with ALS
Phenylbutyrate in patients with ALS
Phase 2
Study Type
Last Updated