The Effect of N-Acetyl Cysteine on Cortical Erosion in Early Stage Schizophrenia (Breier-Stanley)
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|ClinicalTrials.gov Identifier: NCT01339858|
Recruitment Status : Completed
First Posted : April 21, 2011
Results First Posted : May 8, 2019
Last Update Posted : May 8, 2019
|Condition or disease||Intervention/treatment||Phase|
|Schizophrenia Psychotic Disorder NOS Schizoaffective Disorder Schizophreniform||Drug: N-Acetyl Cysteine Other: sugar pill||Phase 4|
Schizophrenia is a severe, debilitating illness that typically begins during the teen-age years and early twenties, and worsens over time as it evolves into a chronic, life-long disorder. Existing treatments suppress psychotic symptoms but do not prevent the evolution of underlying disease processes that results in poor, long term outcomes. Recent studies have shown that progressive erosion of cortical mass occurs during the early stages of schizophrenia (1-3). The investigators hypothesize that arresting cortical erosion during the early phases of schizophrenia will prevent subsequent clinical deterioration and the descending course of illness associated with this disorder. The investigators propose to establish a research program that will assess the ability of agents with neuroprotective properties to halt cortical loss and thereby prevent subsequent clinical deterioration.
N-acetyl cysteine (NAC) is an attractive molecule for the proposed study because of two of its mechanistic properties. First, it is an established neuroprotective agent. NAC is a precursor to glutathione which is a primary detoxifier of reactive oxygen and other radical molecules which damage neuronal tissue (4-6). Glutathione deficiencies have been well documented in schizophrenia (7, 8). Second, NAC modulates glutamate release. NMDA hypofunction and altered glutamate release have been hypothesized to contribute to the cortical atrophy observed in early stage schizophrenia (9, 10). NAC has been shown to antagonize both the phencyclidine (PCP) effects of increased frontal glutamate levels and induction of social isolation in rodents (11). PCP is a pharmacological model of schizophrenia. In a controlled clinical trial of patients with chronic schizophrenia, NAC improved mismatch negativity, a pre-attentive measure of cortical information processing that has been consistently implicated in the pathophysiology of schizophrenia and has been shown to correlate with cortical erosion in early stage patients (12, 13). In a double-blind, placebo controlled clinical trial of chronic schizophrenic patients, NAC significantly improved general psychopathology scores, negative symptoms and extrapyramidal symptoms (14). NAC was well tolerated with no significant effects on any safety parameter or adverse events. The favorable tolerability of NAC has been further demonstrated in a recent study conducted at IUSM Riley Hospital in children (ages 4 to 12 years) with autism at relatively high doses (dose range of 900 to 4200 mg/day) in which there were no serious adverse events reported and NAC was well tolerated (15).
The investigators propose to determine if NAC has disease modifying potential in early stage schizophrenia. The investigators hypothesize that NAC will improve measures of cortical integrity in early stage schizophrenia and these brain effects will be related to improvements in negative symptoms and cognitive functioning. Primary outcome measures in the trials will be serial assessments of cortical integrity using magnetic resonance structural (cortical thickness, cortical volume, diffuses tensor imaging, DTI). In addition the investigators will assess the possible effects of NAC treatment on other parameters linked to cortical erosion including fMRI coupled with working memory and semantic memory tasks, MR spectroscopy (cortical glutathione, N-acetylaspartate, and glutamine/glutamate levels) and electrophysiological measures (e.g., mismatch negativity, P300). The investigators will also determine the relationship between effects of NAC on negative symptoms, positive symptoms, functional status, cognition (BACS), and safety parameters; and brain indices.
|Study Type :||Interventional (Clinical Trial)|
|Actual Enrollment :||60 participants|
|Intervention Model:||Parallel Assignment|
|Masking:||Double (Participant, Care Provider)|
|Study Start Date :||May 2011|
|Actual Primary Completion Date :||December 2015|
|Actual Study Completion Date :||December 2015|
Experimental: N-Acetyl Cysteine
NAC and matched placebo will be supplied in unmarked capsules. Each NAC capsule will contain 600 mg of NAC. Dosing will begin at 600 mg/d and titrated up over 5 weeks until a maximum dose of 3600 mg/d is reached. This approximate dose was effective and well tolerated in a recent study of treatment refractory obsessive-compulsive disorder by Krystal and colleagues at Yale (16). In addition, a double-blind placebo controlled trial recently completed at IUSM Riley Hospital in children (age 4 to 12 years) with autism spectrum disorders used doses ranging from 900 mg/day to 4200 mg/day and reported no serious adverse events and found the agent well tolerated (15). Dose adjustments downward to 1920 mg/d will be permitted if tolerability issues are encountered at the maximum dose.
Drug: N-Acetyl Cysteine
NAC and matched placebo will be supplied in unmarked capsules. Each NAC capsule will contain 480 mg of NAC. Dosing will begin at 480 mg/d and titrated up by 480 mg/d each week until a maximum dose of 2880 mg/d (BID) is reached. This approximate dose was effective and well tolerated in a recent study of treatment refractory obsessive-compulsive disorder by Krystal and colleagues at Yale (16). In addition, a double-blind placebo controlled trial recently completed at IUSM Riley Hospital in children (age 4 to 12 years) with autism spectrum disorders used doses ranging from 900 mg/day to 4200 mg/day and reported no serious adverse events and found the agent well tolerated (15). Dose adjustments downward to 1920 mg/d will be permitted if tolerability issues are encountered at the maximum dose
Placebo Comparator: Sugar Pill
Other: sugar pill
matched placebo will be supplied in unmarked capsules. Dosing regimen will be the same as in the N-Acetyl Cysteine arm.
- Cortical Thickness [ Time Frame: 12 months ]We anticipate that 12 months treatment with NAC as an add-on treatment will show significantly less cortical erosion as measured by cortical thickness than treatment with placebo
- Cortical Volume [ Time Frame: 12 months ]We anticipate that 12 months treatment with NAC as an add-on treatment will show a difference in cortical volume than treatment with placebo
- Working Memory [ Time Frame: Baseline and 12 months ]determine if 12 months of NAC add-on treatment is superior to placebo as determined by brain activity during n-back working memory task during fMRI.
- Number of Participants With Glutamine/Glutamate Level Changes [ Time Frame: 12 months ]Identify number of participants with 12 months of NAC treatment who had glutamine/glutamate level changes as measured by cortical magnetic resonance spectroscopy measures.
- Attention Measures [ Time Frame: 12 months ]determine if 12 months of NAC add-on treatment is superior to placebo for attention measures (e.g., mismatch negativity, P300) as measured by electrophysiology methods. Electrophysiology measures will be recorded from a 64 channel, silver/silver-chloride scalp electrode montage.
- Symptoms of a Psychotic Disorder [ Time Frame: 12 months ]Determine if 12 months of NAC add-on treatment is superior to placebo for symptom management of a psychotic disorder as assessed by the Positive and Negative Syndrome Scale (PANSS). The PANSS is a semi-structured interview, containing 30 items that assess positive, negative, and general psychopathology symptoms. Positive symptoms=7 items, negative symptoms=7 items, and general psych.=16 items. Scores for each item range from 1-absent to 7-extreme. To calculate total score, all items on the scale are summed to yield a score from 30-210,a lower score reflecting fewer symptoms. To calculate factor scores various items from positive, negative, and general psych. are summed together to yield Cognitive/Disorganized, Negative, and Positive factor scores. Cog/Disorg factor scores sum 7 items, ranging from 7-49. Neg factor scores sum 7 items, ranging from 7-49. Pos factor scores sum 8 items, ranging from 8-56. For all factor scores a lower score reflects less symptom severity.
- Cognitive Functioning [ Time Frame: Baseline and 12 months ]determine if 12 months of NAC add-on treatment is superior to placebo for cognitive functioning as measured by the Brief Assessment of Cognition in Schizophrenia (BACS). The BACS is a battery specifically designed to measure treatment-related changes in cognition by utilizing 6 tasks, and has alternate forms, thus minimizing practice effects. Each task generates a raw score (with a higher score indicating better performance): verbal memory 0-75; digit sequencing 0-28; token motor task 0-100; semantic&letter fluency 0-148; symbol coding 0-110; and tower of London 0-22. The raw scores are used to generate a composite score that is calculated by summing t-scores derived by comparisons with a normative sample of 404 healthy controls. The six brief assessments' t-scores, are summed, and averaged to provide a composite t-score. The composite score min and max are between -43 and 100. A higher score indicating better cognitive performance.
- Functional Status [ Time Frame: Baseline and 12 months ]determine if 12 months of NAC add-on treatment is superior to placebo for functional measures as measured by the Personal and Social Performance Scale (PSP). The PSP scale is a 100-point, single item, clinician rated scale to assess 4 domains of functioning, including personal and social relationships, socially useful activities, self care and disturbing and aggressive behaviors. A score from 0-100 is generated, with a higher score representing better performance.
- Mismatch Negativity Voltage Differences [ Time Frame: 12 months ]Determine if 12 months of NAC add-on treatment is superior to placebo for attention measures as measured by the voltage of the Mismatch Negativity (MMN) of the event-related potential. The voltage of the peak MMN response was measured at the Fz electrode site.
- Symptoms of a Psychotic Disorder [ Time Frame: 12 months ]determine if 12 months of NAC add-on treatment is superior to placebo for symptom management of a psychotic disorder as assessed by the Clinical Global Impressions Severity Scale (CGI-S). The CGI-S is used for repeated evaluations of global psychopathology and is a 7 point Likert scale rating severity on a scale of 1 (normal, not ill) to 7 (very severely ill).
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Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT01339858
|United States, Indiana|
|Prevention and Recovery Center for Early Psychosis (PARC)|
|Indianapolis, Indiana, United States, 46202|
|Indiana University Psychotic Disorders Clinic|
|Indianapolis, Indiana, United States, 46222|