Trial Outcomes & Findings for L-arginine in Treatment as Usual in Schizophrenia (NCT NCT00718510)

Last Updated: 2017-09-05

Results Overview

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.

Recruitment status

COMPLETED

Study phase

Target enrollment

13 participants

Primary outcome timeframe

Baseline and 3 Weeks

Results posted on

2017-09-05

Participant Flow

Participant milestones

Participant milestones
Measure	L-arginine Treatment First, Placebo Treatment Second 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.	Placebo Treatment First, L-arginine Treatment Second 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.
First Intervention (3 Weeks) STARTED	7	8
First Intervention (3 Weeks) Received Intervention	7	7
First Intervention (3 Weeks) COMPLETED	7	7
First Intervention (3 Weeks) NOT COMPLETED	0	1
Washout (5 Days) STARTED	7	7
Washout (5 Days) COMPLETED	7	7
Washout (5 Days) NOT COMPLETED	0	0
Second Intervention (3 Weeks) STARTED	7	7
Second Intervention (3 Weeks) COMPLETED	6	7
Second Intervention (3 Weeks) NOT COMPLETED	1	0

Reasons for withdrawal

Reasons for withdrawal
Measure	L-arginine Treatment First, Placebo Treatment Second 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.	Placebo Treatment First, L-arginine Treatment Second 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.
First Intervention (3 Weeks) Withdrawal by Subject	0	1
Second Intervention (3 Weeks) Withdrawal by Subject	1	0

Baseline Characteristics

L-arginine in Treatment as Usual in Schizophrenia

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	L-arginine Treatment First, Placebo Treatment Second n=6 Participants 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.	Placebo Treatment First, L-arginine Treatment Second n=7 Participants 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 n=13 Participants Total of all reporting groups
Age, Continuous	33.8 years STANDARD_DEVIATION 15.1 • n=5 Participants	37.8 years STANDARD_DEVIATION 8.1 • n=7 Participants	36 years STANDARD_DEVIATION 11.5 • n=5 Participants
Sex: Female, Male Female	1 Participants n=5 Participants	0 Participants n=7 Participants	1 Participants n=5 Participants
Sex: Female, Male Male	5 Participants n=5 Participants	7 Participants n=7 Participants	12 Participants n=5 Participants

PRIMARY outcome

Timeframe: Baseline and 3 Weeks

Population: All participants who received all doses of each intervention and completed all study visits were included in the efficacy analysis

Outcome measures

Outcome measures
Measure	L-arginine n=13 Participants Participants who received L-arginine 6 g (500mg capsules) at 0800h and 2000h in either the first or last 3 weeks of the study	Placebo n=13 Participants 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.
Change From Baseline in Mean Positive and Negative Syndrome Scale (PANSS) Total and Positive, Negative and General Psychopathology Subscale Scores at 3 Weeks PANSS Total Score at 3 Weeks	68.0 units on a scale Standard Deviation 7.2	70.2 units on a scale Standard Deviation 7.0
Change From Baseline in Mean Positive and Negative Syndrome Scale (PANSS) Total and Positive, Negative and General Psychopathology Subscale Scores at 3 Weeks PANSS Positive Scale at Baseline	14.6 units on a scale Standard Deviation 4.4	14.3 units on a scale Standard Deviation 4.5
Change From Baseline in Mean Positive and Negative Syndrome Scale (PANSS) Total and Positive, Negative and General Psychopathology Subscale Scores at 3 Weeks PANSS Positive Scale at 3 Weeks	14.5 units on a scale Standard Deviation 4.6	13.6 units on a scale Standard Deviation 4.0
Change From Baseline in Mean Positive and Negative Syndrome Scale (PANSS) Total and Positive, Negative and General Psychopathology Subscale Scores at 3 Weeks PANSS Negative Scale at 3 Weeks	21.9 units on a scale Standard Deviation 5.2	22.2 units on a scale Standard Deviation 5.2
Change From Baseline in Mean Positive and Negative Syndrome Scale (PANSS) Total and Positive, Negative and General Psychopathology Subscale Scores at 3 Weeks PANSS General Psychopathology Score at 3 Weeks	31.2 units on a scale Standard Deviation 3.9	33.6 units on a scale Standard Deviation 3.7
Change From Baseline in Mean Positive and Negative Syndrome Scale (PANSS) Total and Positive, Negative and General Psychopathology Subscale Scores at 3 Weeks PANSS Total Score at Baseline	71.6 units on a scale Standard Deviation 7.2	72.2 units on a scale Standard Deviation 5.7
Change From Baseline in Mean Positive and Negative Syndrome Scale (PANSS) Total and Positive, Negative and General Psychopathology Subscale Scores at 3 Weeks PANSS Negative Scale at Baseline	22.8 units on a scale Standard Deviation 5.0	22.6 units on a scale Standard Deviation 4.3
Change From Baseline in Mean Positive and Negative Syndrome Scale (PANSS) Total and Positive, Negative and General Psychopathology Subscale Scores at 3 Weeks PANSS General Psychopathology Score at Baseline	33.4 units on a scale Standard Deviation 4.4	34.4 units on a scale Standard Deviation 2.7

SECONDARY outcome

Timeframe: Baseline and 3 Weeks

Population: All participants who received all doses of each intervention and completed all study visits were included in the efficacy analysis

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.

Outcome measures

Outcome measures
Measure	L-arginine n=13 Participants Participants who received L-arginine 6 g (500mg capsules) at 0800h and 2000h in either the first or last 3 weeks of the study	Placebo n=13 Participants 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.
Change From Baseline in Mean Clinical Global Impression (CGI) Scale at 3 Weeks CGI Score at Baseline	4.0 units on a scale Standard Deviation 0	4.0 units on a scale Standard Deviation 0
Change From Baseline in Mean Clinical Global Impression (CGI) Scale at 3 Weeks CGI Score at 3 Weeks	3.6 units on a scale Standard Deviation 0.5	3.7 units on a scale Standard Deviation 0.4

SECONDARY outcome

Timeframe: Baseline and 3 Weeks

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.

Outcome measures

Outcome measures
Measure	L-arginine n=13 Participants Participants who received L-arginine 6 g (500mg capsules) at 0800h and 2000h in either the first or last 3 weeks of the study	Placebo n=13 Participants 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.
Change From Baseline in Mean Calgary Depression Scale for Schizophrenia (CDSS) at 3 Weeks CDSS at Baseline	4.5 units on a scale Standard Deviation 3.4	4.5 units on a scale Standard Deviation 2.8
Change From Baseline in Mean Calgary Depression Scale for Schizophrenia (CDSS) at 3 Weeks CDSS at 3 Weeks	3.4 units on a scale Standard Deviation 2.7	3.8 units on a scale Standard Deviation 2.1

Adverse Events

L-arginine

Serious events: 0 serious events

Other events: 0 other events

Deaths: 0 deaths

Placebo

Serious events: 0 serious events

Other events: 0 other events

Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Adverse event data not reported

Additional Information

Dr. Serdar Dursun

Department of Psychiatry, University of Alberta

Phone: (780) 492-7319

Email: [email protected]

Results disclosure agreements

Principal investigator is a sponsor employee
Publication restrictions are in place