None listed
Conditions
Brief summary
This study seeks to elucidate the benefits of NAC augmentation (2-4 grams/day) compared to placebo in the treatment of OCD, in a 24-week, multi-centre, randomized, double-blind, placebo controlled trial. It is hypothesized that NAC will be superior over placebo for improving OCD symptoms as measured by a reduction in Y-BOCS scores from baseline against each subsequent time point (W4, W8, W12, W16, W20 and W24). Additional benefits are anticipated for relieving anxiety as well as improving mood, functioning and overall quality of life.
Interventions
The amino acid N-acetyl cysteine (NAC; 500mg per capsule, taken orally) or placebo (capsules containing microcellulose), used adjunctive to stable medication (minimum 8-weeks at consistent dosages) for 24 weeks in adults (18-75 years of age) with OCD.
Randomised participants will take 2 capsules, twice per day (equating to 2,000mg NAC or placebo per day) for the first 8-weeks of the study. However, the dose of NAC (or placebo) may increase from the week-8 visit. In cases of non-response (<35% r
The amino acid N-acetyl cysteine (NAC; 500mg per capsule, taken orally) or placebo (capsules containing microcellulose), used adjunctive to stable medication (minimum 8-weeks at consistent dosages) for 24 weeks in adults (18-75 years of age) with OCD. Randomised participants will take 2 capsules, twice per day (equating to 2,000mg NAC or placebo per day) for the first 8-weeks of the study. However, the dose of NAC (or placebo) may increase from the week-8 visit. In cases of non-response (<35% reduction in baseline score of primary outcome measure: Y-BOCS), participants will increase their dose by an additional 1,000mg per day (3 capsules taken orally twice per day; equating to 3,000mg NAC or placebo per day) from week-8 and remain on this dose for the following 4-weeks. If the participant continues to be non-responsive at the week-12 visit, an additional 1,000mg may be added (4 capsules taken orally twice per day). The maximum dose permitted in this study will be 4,000mg per day, however, participants will only be permitted to increase their dose by 1,000mg (per day) at a time and must remain on this dose for a minimum of 4-weeks before further titration can occur. Titration may occur at week-8, week-12, week-16 and week-20 in cases of non response. If the participant has reported any side effects/adverse events, titration will only occur if deemed suitable by the medical investigators. Participants will be asked to return all remaining capsules in their containers at each study follow-up visit. Remaining capsules will be counted by a 3rd party to determine participant compliance.
Sponsors
The University of Melbourne
Study design
Allocation
Randomised controlled trial
Intervention model
Parallel
Primary purpose
Treatment
Masking
Blinded (masking used) (Subject, Caregiver, Investigator, Outcomes Assessor)
Eligibility
Sex/Gender
All
Age
18 Years to 75 Years
Healthy volunteers
No
Inclusion criteria
Primary diagnosis of OCD as per the Structured Interview Guide for the DSM-5 (SCID) Adults between the age of 18-75 who have the desire and capacity to consent to the study and follow its procedures. Minimum score of 16 on the Y-BOCS at time of entry into the study, but no greater than 31. Currently taking medication for their OCD which has been at a stable dose for the past 8-weeks. Stable psychological treatment (if employing) for minimum eight weeks (an 8-week wash-out period will be required if participants have just completed an intensive in-patient CBT program for their OCD).
Exclusion criteria
*Bipolar disorder *Psychotic disorders *Primary diagnosis of Obsessive-compulsive spectrum disorders including hoarding, body dysmorphic disorder, trichotillomania (secondary diagnosis permitted) *Severe depression (as defined by HAM-D score equal to or greater than 24 *Alcohol/substance abuse *Y-BOCS score equal to or greater than 32 *Treatment resistant OCD (3 or more trials of first line medications for their OCD at therapeutic doses for minimum of 12-weeks each, at least one augmentation strategy, for example, anti psychotic medication as well as exposure response prevention therapy minimum 20 hours) *Medications with known or suspected negative interactions with NAC (activated charcoal, nitro glycerine, insulin replacement therapies, Aralen, anti-coagulant medications excluding aspirin and NSAIDS)
Outcome results
None listed