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Signal Attenuation as a Rat Model of Obsessive Compulsive Disorder
Published on: January 9, 2015
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Tolcapone in obsessive-compulsive disorder: a randomized double-blind placebo-controlled crossover trial
Jon E Grant1, Roxanne Hook2, Stephanie Valle1
1University of Chicago, Department of Psychiatry and Behavioral Neuroscience, Chicago, Illinois, USA.
International Clinical Psychopharmacology
|July 26, 2021
Summary
Tolcapone, a catechol-O-methyl-transferase (COMT) inhibitor, significantly reduced obsessive-compulsive disorder (OCD) symptoms compared to placebo. This proof-of-concept study suggests COMT inhibitors warrant further investigation for OCD treatment.
Area of Science:
- Neuroscience
- Psychiatry
- Pharmacology
Background:
- Evidence-based treatments for obsessive-compulsive disorder (OCD) do not benefit all patients.
- Tolcapone, a catechol-O-methyl-transferase (COMT) enzyme inhibitor, enhances cortical dopaminergic transmission.
Purpose of the Study:
- To conduct a proof-of-concept study investigating if a COMT inhibitor reduces OCD symptoms more effectively than a placebo.
- To evaluate tolcapone's efficacy in treating OCD.
Main Methods:
- A randomized, placebo-controlled, double-blind crossover trial was conducted with 20 adults diagnosed with OCD.
- Participants received 2 weeks of tolcapone followed by 2 weeks of placebo, with a 1-week washout period in between.
- OCD symptom severity and psychosocial functioning were assessed at baseline and after each treatment phase.
Main Results:
- Two weeks of tolcapone treatment showed a significant improvement in OCD symptoms compared to placebo (t = 2.194, P = 0.0409).
- The mean percentage decrease in Yale-Brown Obsessive-Compulsive Scale (YBOCS) scores was 16.4% for tolcapone versus 3.6% for placebo.
Conclusions:
- Brain-penetrant COMT inhibitors show promise as a novel therapeutic strategy for OCD.
- Further investigation into COMT inhibitors for OCD treatment is warranted based on these findings.
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