Trial of Sodium Phenylbutyrate-Taurursodiol for Amyotrophic Lateral Sclerosis

N Engl J Med. 2020 Sep 3;383(10):919-930. doi: 10.1056/NEJMoa1916945.

Abstract

Background: Sodium phenylbutyrate and taurursodiol have been found to reduce neuronal death in experimental models. The efficacy and safety of a combination of the two compounds in persons with amyotrophic lateral sclerosis (ALS) are not known.

Methods: In this multicenter, randomized, double-blind trial, we enrolled participants with definite ALS who had had an onset of symptoms within the previous 18 months. Participants were randomly assigned in a 2:1 ratio to receive sodium phenylbutyrate-taurursodiol (3 g of sodium phenylbutyrate and 1 g of taurursodiol, administered once a day for 3 weeks and then twice a day) or placebo. The primary outcome was the rate of decline in the total score on the Amyotrophic Lateral Sclerosis Functional Rating Scale-Revised (ALSFRS-R; range, 0 to 48, with higher scores indicating better function) through 24 weeks. Secondary outcomes were the rates of decline in isometric muscle strength, plasma phosphorylated axonal neurofilament H subunit levels, and the slow vital capacity; the time to death, tracheostomy, or permanent ventilation; and the time to death, tracheostomy, permanent ventilation, or hospitalization.

Results: A total of 177 persons with ALS were screened for eligibility, and 137 were randomly assigned to receive sodium phenylbutyrate-taurursodiol (89 participants) or placebo (48 participants). In a modified intention-to-treat analysis, the mean rate of change in the ALSFRS-R score was -1.24 points per month with the active drug and -1.66 points per month with placebo (difference, 0.42 points per month; 95% confidence interval, 0.03 to 0.81; P = 0.03). Secondary outcomes did not differ significantly between the two groups. Adverse events with the active drug were mainly gastrointestinal.

Conclusions: Sodium phenylbutyrate-taurursodiol resulted in slower functional decline than placebo as measured by the ALSFRS-R score over a period of 24 weeks. Secondary outcomes were not significantly different between the two groups. Longer and larger trials are necessary to evaluate the efficacy and safety of sodium phenylbutyrate-taurursodiol in persons with ALS. (Funded by Amylyx Pharmaceuticals and others; CENTAUR ClinicalTrials.gov number, NCT03127514.).

Publication types

  • Clinical Trial, Phase II
  • Multicenter Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Amyotrophic Lateral Sclerosis / drug therapy*
  • Disease Progression
  • Double-Blind Method
  • Drug Combinations
  • Female
  • Humans
  • Intention to Treat Analysis
  • Male
  • Middle Aged
  • Phenylbutyrates / adverse effects
  • Phenylbutyrates / therapeutic use*
  • Severity of Illness Index
  • Taurochenodeoxycholic Acid / administration & dosage
  • Taurochenodeoxycholic Acid / therapeutic use*
  • Treatment Outcome

Substances

  • Drug Combinations
  • Phenylbutyrates
  • Taurochenodeoxycholic Acid
  • ursodoxicoltaurine
  • 4-phenylbutyric acid

Associated data

  • ClinicalTrials.gov/NCT03127514