Phase 2 study of sodium phenylbutyrate in ALS.

Abstract

The objective of the study was to establish the safety and pharmacodynamics of escalating dosages of sodium phenylbutyrate (NaPB) in participants with ALS. Transcription dysregulation may play a role in the pathogenesis of ALS. Sodium phenylbutyrate, a histone deacetylase inhibitor, improves transcription and post-transcriptional pathways, promoting cell survival in a mouse model of motor neuron disease. Forty research participants at eight sites enrolled in an open-label study. Study medication was increased from 9 to 21 g/day. The primary outcome measure was tolerability. Secondary outcome measures included adverse events, blood histone acetylation levels, and NaPB blood levels at each dosage. Twenty-six participants completed the 20-week treatment phase. NaPB was safe and tolerable. No study deaths or clinically relevant laboratory changes occurred with NaPB treatment. Histone acetylation was decreased by approximately 50% in blood buffy-coat specimens at screening and was significantly increased after NaPB administration. Blood levels of NaPB and the primary metabolite, phenylacetate, increased with dosage. While the majority of subjects tolerated higher dosages of NaPB, the lowest dose (9 g/day), was therapeutically efficient in improving histone acetylation levels.

• Authors: Merit E Cudkowicz, Patricia L Andres, Sally A Macdonald, Richard S Bedlack, Rabia Choudry, Robert H Brown Jr, Hui Zhang, David A Schoenfeld, Jeremy Shefner, Samantha Matson, Wayne R Matson, Robert J Ferrante, Northeast ALS and National VA ALS Research Consortiums
• Journal: Amyotrophic lateral sclerosis : official publication of the World Federation of Neurology Research Group on Motor Neuron Diseases (Amyotroph Lateral Scler) Vol. 10 Issue 2 Pg. 99-106 (Apr 2009) ISSN: 1471-180X [Electronic] England
• PMID: 18688762 (Publication Type: Clinical Trial, Phase II, Journal Article, Multicenter Study, Research Support, Non-U.S. Gov't, Research Support, U.S. Gov't, Non-P.H.S.)

Chemical References

• Anticonvulsants
• Enzyme Inhibitors
• Histone Deacetylase Inhibitors
• Phenylacetates
• Phenylbutyrates
• Histone Deacetylases
• phenylacetic acid

Topics

• Aged
• Amyotrophic Lateral Sclerosis (drug therapy)
• Anticonvulsants (administration & dosage, blood)
• Dose-Response Relationship, Drug
• Drug Therapy, Combination
• Enzyme Inhibitors (administration & dosage, adverse effects, pharmacokinetics)
• Female
• Histone Deacetylase Inhibitors
• Histone Deacetylases (metabolism)
• Humans
• Male
• Middle Aged
• Motor Neurons (drug effects, enzymology)
• Phenylacetates (administration & dosage, blood)
• Phenylbutyrates (administration & dosage, adverse effects, pharmacokinetics)