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L-arginine in Treatment as Usual in Schizophrenia

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ClinicalTrials.gov Identifier: NCT00718510
Recruitment Status : Completed
First Posted : July 18, 2008
Results First Posted : September 5, 2017
Last Update Posted : September 5, 2017
Sponsor:
Collaborator:
Alberta Health Services
Information provided by (Responsible Party):
Serdar Dursun, University of Alberta

Study Type Interventional
Study Design Allocation: Randomized;   Intervention Model: Crossover Assignment;   Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor);   Primary Purpose: Treatment
Condition Schizophrenia
Intervention Drug: L-Arginine
Enrollment 13
Recruitment Details  
Pre-assignment Details  
Arm/Group Title L-arginine Treatment First, Placebo Treatment Second Placebo Treatment First, L-arginine Treatment Second
Hide Arm/Group Description The trial participants received 6 g p.o. (3 g twice per day at 0800h and 2000h) of L-arginine 500mg capsules for 3 weeks in addition to their antipsychotic treatment as usual. After a 5 day washout period, they then received placebo capsules (matching L-arginine 500mg) 6g p.o. (3 g twice per day at 0800h and 2000h) for 3 weeks in addition to their antipsychotic treatment as usual. The trial participants received the placebo capsules (matching L-arginine 500mg) 6 g p.o. (3 g twice per day at 0800h and 2000h) for 3 weeks in addition to their antipsychotic treatment as usual. After a 5 day washout period, they then received L-arginine (500mg capsules) 6g p.o. (3 g twice per day at 0800h and 2000h) for 3 weeks in addition to their antipsychotic treatment as usual.
Period Title: First Intervention (3 Weeks)
Started 7 8
Received Intervention [1] 7 7
Completed 7 7
Not Completed 0 1
Reason Not Completed
Withdrawal by Subject             0             1
[1]
Received Intervention
Period Title: Washout (5 Days)
Started 7 7
Completed 7 7
Not Completed 0 0
Period Title: Second Intervention (3 Weeks)
Started 7 7
Completed 6 7
Not Completed 1 0
Reason Not Completed
Withdrawal by Subject             1             0
Arm/Group Title L-arginine Treatment First, Placebo Treatment Second Placebo Treatment First, L-arginine Treatment Second Total
Hide Arm/Group Description The trial participants received 6 g p.o. (3 g twice per day at 0800h and 2000h) of L-arginine 500mg capsules for 3 weeks in addition to their antipsychotic treatment as usual. After a 5 day washout period, they then received placebo capsules (matching L-arginine 500mg) 6g p.o. (3 g twice per day at 0800h and 2000h) for 3 weeks in addition to their antipsychotic treatment as usual. The trial participants received the placebo capsules (matching L-arginine 500mg) 6 g p.o. (3 g twice per day at 0800h and 2000h) for 3 weeks in addition to their antipsychotic treatment as usual. After a 5 day washout period, they then received L-arginine (500mg capsules) 6g p.o. (3 g twice per day at 0800h and 2000h) for 3 weeks in addition to their antipsychotic treatment as usual. Total of all reporting groups
Overall Number of Baseline Participants 6 7 13
Hide Baseline Analysis Population Description
[Not Specified]
Age, Continuous  
Mean (Standard Deviation)
Unit of measure:  Years
Number Analyzed 6 participants 7 participants 13 participants
33.8  (15.1) 37.8  (8.1) 36  (11.5)
Sex: Female, Male  
Measure Type: Count of Participants
Unit of measure:  Participants
Number Analyzed 6 participants 7 participants 13 participants
Female
1
  16.7%
0
   0.0%
1
   7.7%
Male
5
  83.3%
7
 100.0%
12
  92.3%
1.Primary Outcome
Title Change From Baseline in Mean Positive and Negative Syndrome Scale (PANSS) Total and Positive, Negative and General Psychopathology Subscale Scores at 3 Weeks
Hide Description The primary outcome measure was the Positive and Negative Syndrome Scale (PANSS) total score and PANSS positive, negative and general psychopathology subscale scores. The PANSS is a 30-item scale used to evaluate the symptoms of schizophrenia. For each PANSS item, symptom severity was rated on a 7-point scale, from 1=absent to 7=extreme. The PANSS total score (30 items) ranges from 30 to 210 with a higher score indicating a greater severity of symptoms. The PANSS positive symptom subscale score (7 items) ranges from 7=absent to 49=extreme; the PANSS negative subscale score (7 items) ranges from 7=absent to 49=extreme; and the PANSS general psychopathology subscare score (16 items) ranges from 16=absent to 112=extreme.
Time Frame Baseline and 3 Weeks
Hide Outcome Measure Data
Hide Analysis Population Description
All participants who received all doses of each intervention and completed all study visits were included in the efficacy analysis
Arm/Group Title L-arginine Placebo
Hide Arm/Group Description:
Participants who received L-arginine 6 g (500mg capsules) at 0800h and 2000h in either the first or last 3 weeks of the study
Participants who received Placebo 6 g (matching L-arginine 500mg capsules) at 0800h and 2000h in either the first or last 3 weeks of the study.
Overall Number of Participants Analyzed 13 13
Mean (Standard Deviation)
Unit of Measure: units on a scale
PANSS Total Score at Baseline 71.6  (7.2) 72.2  (5.7)
PANSS Total Score at 3 Weeks 68.0  (7.2) 70.2  (7.0)
PANSS Positive Scale at Baseline 14.6  (4.4) 14.3  (4.5)
PANSS Positive Scale at 3 Weeks 14.5  (4.6) 13.6  (4.0)
PANSS Negative Scale at Baseline 22.8  (5.0) 22.6  (4.3)
PANSS Negative Scale at 3 Weeks 21.9  (5.2) 22.2  (5.2)
PANSS General Psychopathology Score at Baseline 33.4  (4.4) 34.4  (2.7)
PANSS General Psychopathology Score at 3 Weeks 31.2  (3.9) 33.6  (3.7)
Show Statistical Analysis 1 Hide Statistical Analysis 1
Statistical Analysis Overview Comparison Group Selection L-arginine, Placebo
Comments Null hypothesis is that there was no difference in change of PANSS between L-arginine and Placebo. A two-factor ANOVA was used across all subjects with the within-subject factor being the treatment phase (L-arginine first/Placebo second or Placebo first/L-arginine second) and the between-subject factor being the day of treatment (time). A sample size of 14 patients was needed to give 90% power to detect a 4 point difference on the PANSS. This included a drop-out rate of about 10%.
Type of Statistical Test Other
Comments [Not Specified]
Statistical Test of Hypothesis P-Value <0.05
Comments General Psychopathology Subscale Score
Method ANOVA
Comments F(1,11)=5.03
2.Secondary Outcome
Title Change From Baseline in Mean Clinical Global Impression (CGI) Scale at 3 Weeks
Hide Description The Secondary Outcome Measure was the Clinical Global Impression (CGI) scale. The CGI is a 3-item scale that rates treatment response and monitors the clinical course of all psychiatric illnesses including schizophrenia. Within the CGI, the Severity of Illness was rated on a 7-point scale, 0=not assessed to 7=among the most severely ill patients. For Global Improvement, the total improvement following treatment as compared to at baseline of the trial was rated on a 7-point scale, 0=not assessed to 7=very much worse.
Time Frame Baseline and 3 Weeks
Hide Outcome Measure Data
Hide Analysis Population Description
All participants who received all doses of each intervention and completed all study visits were included in the efficacy analysis
Arm/Group Title L-arginine Placebo
Hide Arm/Group Description:
Participants who received L-arginine 6 g (500mg capsules) at 0800h and 2000h in either the first or last 3 weeks of the study
Participants who received Placebo 6 g (matching L-arginine 500mg capsules) at 0800h and 2000h in either the first or last 3 weeks of the study.
Overall Number of Participants Analyzed 13 13
Mean (Standard Deviation)
Unit of Measure: units on a scale
CGI Score at Baseline 4.0  (0) 4.0  (0)
CGI Score at 3 Weeks 3.6  (0.5) 3.7  (0.4)
Show Statistical Analysis 1 Hide Statistical Analysis 1
Statistical Analysis Overview Comparison Group Selection L-arginine, Placebo
Comments Null hypothesis is that there was no difference in change of CGI ratings between L-arginine and Placebo. A two-factor ANOVA was used across all subjects with the within-subject factor being the treatment phase (L-arginine first/Placebo second or Placebo first/L-arginine second) and the between-subject factor being the day of treatment (time).
Type of Statistical Test Other
Comments [Not Specified]
Statistical Test of Hypothesis P-Value 0.46
Comments [Not Specified]
Method ANOVA
Comments [Not Specified]
3.Secondary Outcome
Title Change From Baseline in Mean Calgary Depression Scale for Schizophrenia (CDSS) at 3 Weeks
Hide Description The Secondary Outcome Measure was the Calgary Depression Scale for Schizophenia (CDSS). The CDSS is a 9-item scale that is used to rate the depressive symptoms in patients with schizophrenia. For each CDSS item, symptom severity was rated on a 3-point scale, from 0=absent to 3=severe. The CDSS total score ranges from 0 to 27 with a higher score indicating a greater severity of symptoms.
Time Frame Baseline and 3 Weeks
Hide Outcome Measure Data
Hide Analysis Population Description
[Not Specified]
Arm/Group Title L-arginine Placebo
Hide Arm/Group Description:
Participants who received L-arginine 6 g (500mg capsules) at 0800h and 2000h in either the first or last 3 weeks of the study
Participants who received Placebo 6 g (matching L-arginine 500mg capsules) at 0800h and 2000h in either the first or last 3 weeks of the study.
Overall Number of Participants Analyzed 13 13
Mean (Standard Deviation)
Unit of Measure: units on a scale
CDSS at Baseline 4.5  (3.4) 4.5  (2.8)
CDSS at 3 Weeks 3.4  (2.7) 3.8  (2.1)
Show Statistical Analysis 1 Hide Statistical Analysis 1
Statistical Analysis Overview Comparison Group Selection L-arginine, Placebo
Comments Null hypothesis is that there was no difference in change of CDSS ratings between L-arginine and Placebo. A two-factor ANOVA was used across all subjects with the within-subject factor being the treatment phase (L-arginine first/Placebo second or Placebo first/L-arginine second) and the between-subject factor being the day of treatment (time).
Type of Statistical Test Other
Comments [Not Specified]
Statistical Test of Hypothesis P-Value 0.55
Comments [Not Specified]
Method ANOVA
Comments [Not Specified]
Time Frame Three weeks for each intervention
Adverse Event Reporting Description Safety population included all participants that received at least one dose of the intervention
 
Arm/Group Title L-arginine Placebo
Hide Arm/Group Description Participants who received L-arginine 6 g (500mg capsules) at 0800h and 2000h in either the first or last 3 weeks of the study Participants who received Placebo 6 g (matching L-arginine 500mg capsules) at 0800h and 2000h in either the first or last 3 weeks of the study.
All-Cause Mortality
L-arginine Placebo
Affected / at Risk (%) Affected / at Risk (%)
Total   0/13 (0.00%)   0/13 (0.00%) 
Show Serious Adverse Events Hide Serious Adverse Events
L-arginine Placebo
Affected / at Risk (%) Affected / at Risk (%)
Total   0/13 (0.00%)   0/13 (0.00%) 
Show Other (Not Including Serious) Adverse Events Hide Other (Not Including Serious) Adverse Events
Frequency Threshold for Reporting Other Adverse Events 0%
L-arginine Placebo
Affected / at Risk (%) Affected / at Risk (%)
Total   0/13 (0.00%)   0/13 (0.00%) 
Certain Agreements
Principal Investigators are NOT employed by the organization sponsoring the study.
There is NOT an agreement between Principal Investigators and the Sponsor (or its agents) that restricts the PI's rights to discuss or publish trial results after the trial is completed.
Results Point of Contact
Layout table for Results Point of Contact information
Name/Title: Dr. Serdar Dursun
Organization: Department of Psychiatry, University of Alberta
Phone: (780) 492-7319
EMail: dursun@ualberta.ca
Layout table for additonal information
Responsible Party: Serdar Dursun, University of Alberta
ClinicalTrials.gov Identifier: NCT00718510     History of Changes
Other Study ID Numbers: CPAT7176
First Submitted: July 16, 2008
First Posted: July 18, 2008
Results First Submitted: May 1, 2017
Results First Posted: September 5, 2017
Last Update Posted: September 5, 2017