D-serine AudRem: R33 Phase

January 5, 2024 updated by: Joshua Kantrowitz, New York State Psychiatric Institute

D-serine Augmentation of Neuroplasticity-based Auditory Learning in Schizophrenia: R33 Phase

Schizophrenia is a major public health problem associated with cognitive deficits, such as short and long term memory, executive functioning, attention and speed of processing that are amongst the strongest predictors of impaired functional outcome. In addition, schizophrenia patients show reduced "plasticity", defined as reduced learning.

D-serine is a naturally occurring activator of the N-methyl-d-aspartate-type glutamate receptors (NMDAR) in the brain, and this project will assess the D-serine treatment over 16 weeks of a program designed to measure auditory plasticity.

Study Overview

Status

Suspended

Intervention / Treatment

Detailed Description

D-Serine is a naturally occurring substance in the brain that activates the N-methyl-d-aspartate-type glutamate receptor (NMDAR). This receptor is thought to be important in both schizophrenia and plasticity (learning). My model proposes that problems with NMDAR within the brain leads to impaired plasticity, which in turn leads to impaired cognition. d-serine is an ideal NMDAR activator to study because it balances efficacy, availability and safety. Most d-serine studies have used a low dose, but the evidence for efficacy is even stronger for high dose d-serine, as will be tested in the current study. There has only been limited summary of higher dose d-serine, which is another important reason for this study.

In addition to testing a potentially viable treatment in schizophrenia, a positive result would provide opportunities for use of D-serine in other populations (e.g. anxiety disorders or dementia) and stimulate the pharmaceutical industry to utilize this methodology to assess the efficacy of novel NMDAR modulators, using d-serine as a "gold-standard."

The ultimate goal of this two part grant (R61-R33) study is to improve cognitive remediation by augmenting with D-serine.

We recently completed the R61-phase, meeting our predetermined "milestones. " As predicted, D-serine led to significant enhancement of auditory plasticity and electrophysiological measures.

During the three-year R33-phase, we will conduct a study of D-serine of 60 schizophrenia patients, assessing the effects of D-serine over 16 sessions of this program. Most successful, cognitive remediation programs are limited by lengthy (30-50 hours) treatments. Hypothesizing that adding D-serine will increase efficiency of cognitive remediation, successful completion of the R33-phase is defined as significant improvement in global cognition after 16 hours of treatment, and will serve as a pilot study to determine whether future, definitive clinical trials are warranted.

Study Type

Interventional

Enrollment (Estimated)

60

Phase

  • Phase 2
  • Phase 1

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Locations

    • New York
      • New York, New York, United States, 10032
        • NYSPI

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

18 years to 50 years (Adult)

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  1. Age between 18 and 50
  2. DSM-V diagnosis of schizophrenia or schizoaffective disorder
  3. Willing to provide informed consent
  4. Auditory Cognitive impairment demonstrated by:

    a .MCCB composite domain score less than or equal to 0.5 standard deviation below normal (T score less than or equal to 45) b. And at least one of the following:

  5. MCCB verbal memory domain score less than or equal to 0.5 standard deviation below normal (T score less than or equal to 45)
  6. Tone matching score of less than or equal to 77.7%
  7. Clinically stable for 2 months (CGI less than or equal to 4)
  8. Moderate or lower cognitive disorganization (PANSS P2 less than or equal to 4)
  9. Medically stable for study participation
  10. Willing to use qualified methods of contraception for the study duration and up to 2 months after its end
  11. Fluent English speaker
  12. Normal hearing
  13. Visual acuity corrected to 20/30
  14. An estimated Glomerular Filtration Rate (GFR) greater than or equal to 60
  15. Taking an antipsychotic medication other than clozapine at a stable dose for at least 4 weeks
  16. Judged clinically not to be at significant suicide or violence risk

Exclusion Criteria:

  1. Substance abuse (excluding nicotine) within last 60 days
  2. ECG abnormality that is clinically significant in the context of study participation in the opinion of the study cardiologist
  3. Current clozapine use. Clozapine is excluded for two reasons: to avoid the potential confound of treatment resistant patients and because of clozapine's intrinsic NMDA agonist
  4. Participation in study of investigational medication/device within 4 weeks
  5. Pregnant women or women of child-bearing potential, who are either not surgically-sterile or for outpatients, using appropriate methods of birth control. Women of child-bearing potential must have a negative serum beta-hCG pregnancy test at screening.
  6. Presence of positive history of unstable significant medical or neurological illness
  7. Positive toxicology screen for any substances of abuse
  8. Subjects with suicidal ideation with intent or plan (indicated by affirmative answers to items 4 or 5 of the Suicidal Ideation section of the baseline C-SSRS) in the 6 months prior to screening or subjects who represent a significant risk of suicide in the opinion of the investigator

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Quadruple

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: D-serine
Subjects will receive 16 sessions of auditory remediation paired with either D-serine or Placebo in a 1:1 D-serine 120 mg/kg:placebo ratio.
Auditory remediation +/-D-serine
Placebo Comparator: placebo
Subjects will receive 16 sessions of auditory remediation paired with either D-serine or Placebo in a 1:1 D-serine 120 mg/kg:placebo ratio.
Auditory remediation +/-D-serine

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Auditory Cognition
Time Frame: 16 weeks
MATRICS cognitive battery verbal domain
16 weeks

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

December 1, 2022

Primary Completion (Estimated)

April 1, 2025

Study Completion (Estimated)

August 31, 2025

Study Registration Dates

First Submitted

August 30, 2021

First Submitted That Met QC Criteria

September 7, 2021

First Posted (Actual)

September 16, 2021

Study Record Updates

Last Update Posted (Actual)

January 9, 2024

Last Update Submitted That Met QC Criteria

January 5, 2024

Last Verified

January 1, 2024

More Information

Terms related to this study

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

UNDECIDED

IPD Plan Description

Will likely be available at https://nda.nih.gov

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

Yes

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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