Allopurinol in Schizophrenia: A Randomized Trial Administering Allopurinol vs Placebo as add-on Antipsychotics in Patients With Schizophrenia

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT00864825
Recruitment Status : Completed
First Posted : March 19, 2009
Last Update Posted : May 8, 2012
Information provided by (Responsible Party):
Sheba Medical Center

March 17, 2009
March 19, 2009
May 8, 2012
August 2009
December 2009   (Final data collection date for primary outcome measure)
PANSS total score. [ Time Frame: 6 weeks ]
Same as current
Complete list of historical versions of study NCT00864825 on Archive Site
PANSS positive, negative and general psychopathology scales, BACS, CGI, Simpson-Angus Scale. [ Time Frame: 6 weeks ]
Same as current
Not Provided
Not Provided
Allopurinol in Schizophrenia: A Randomized Trial Administering Allopurinol vs Placebo as add-on Antipsychotics in Patients With Schizophrenia
Allopurinol in Schizophrenia: A Randomized Trial Administering Allopurinol vs Placebo as add-on Antipsychotics in Patients With Schizophrenia
The objective of the study is to evaluate the efficacy of allopurinol, compared to placebo, as add-on to anti-psychotics in the treatment of patients with schizophrenia.

An emerging body of evidence supports a purinergic hypothesis for schizophrenia. Adenosine agonists have been shown to have properties similar to those of dopamine antagonists and there is a well characterized antagonistic interaction between adenosine and dopamine receptors in the ventral striatum1. Increased adenosinergic transmission has been demonstrated to reduce the affinity of dopamine agonists for dopamine receptors. It has been theorized that adenosine may exert some of its antipsychotic effects through modulation of glutamatergic transmission.

Three double-blind, randomized, placebo-controlled trials have showed statistically significant greater improvements in PANSS scores in the allopurinol groups vs. placebo groups. These empiric data, together with the theoretical and basic science background cited, provide the impetus for this proposed study.

Phase 4
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Triple (Participant, Care Provider, Investigator)
Primary Purpose: Treatment
  • Schizophrenia
  • Schizoaffective Disorder
Drug: Allopurinol
Allopurinol 1 capsule 300 mg, or placebo, bid (twice a day) for 42 days.
Other Name: Alloril, Zylol, Zyloric
  • Experimental: Allopurinol
    Intervention: Drug: Allopurinol
  • Placebo Comparator: Placebo
    Intervention: Drug: Allopurinol
Weiser M, Gershon AA, Rubinstein K, Petcu C, Ladea M, Sima D, Podea D, Keefe RS, Davis JM. A randomized controlled trial of allopurinol vs. placebo added on to antipsychotics in patients with schizophrenia or schizoaffective disorder. Schizophr Res. 2012 Jun;138(1):35-8. doi: 10.1016/j.schres.2012.02.014. Epub 2012 Apr 4.

*   Includes publications given by the data provider as well as publications identified by Identifier (NCT Number) in Medline.
January 2010
December 2009   (Final data collection date for primary outcome measure)

Inclusion Criteria:

  1. Male or female, 18-65 years of age, inclusive
  2. Because gout is relatively rare in women of childbearing age, there are few reports describing the use of allopurinol during pregnancy; in those there were no adverse fetal outcomes attributable to allopurinol. Therefore, only females who are abstinent or practicing an established method of birth control (oral contraceptive tablets, hormonal implant device, hormone patch, injectable contraceptive, intrauterine device [IUD]) can be included in the trial.
  3. Willing and able to provide informed consent, after the nature of the study has been fully explained
  4. Current DSM-IV-TR diagnosis of schizophrenia as confirmed by SCID
  5. Symptoms: 4 (moderate) or above on CGI-S AND >= 4 (moderate) score on two of the following four PANSS items: delusions, hallucinatory behaviors, conceptual disorganization or suspiciousness/ persecution.
  6. Must be on any antipsychotic drug for at least 2 weeks prior to the baseline visit, at doses within the PORT criteria. Patients receiving higher doses will have their records reviewed to insure that dose is required. Patients receiving two anti-psychotics, or IM depot antipsychotics can also be included.
  7. Inpatients or outpatients.

Exclusion Criteria:

  1. Unwilling or unable, in the opinion of the Investigator, to comply with study instructions
  2. Pregnant or breast-feeding
  3. Unstable medical disease (malignancy, poorly controlled diabetes, active ischemic cardiac disease, or cardiomyopathy, serious pulmonary disease, , kidney disease, impaired liver functioning
  4. Likely allergy or sensitivity to allopurinol
  5. At significant risk of committing suicide, or in the opinion of the Investigator, currently is at imminent risk of suicide or harming others.
  6. Suffers from a significant Substance Dependence disorder based on DSM-IV criteria within the 3 months prior to Screening, or is deemed by the Investigator to have a high risk of substance use during the study. Patients with a history of recreational use of cannabinoids or alcohol, and/or patients who smoke cigarettes can be included.
  7. Concurrent delirium, mental retardation, drug-induced psychosis, or history of brain trauma.
Sexes Eligible for Study: All
18 Years to 65 Years   (Adult)
Contact information is only displayed when the study is recruiting subjects
Israel,   Romania
Not Provided
Not Provided
Sheba Medical Center
Sheba Medical Center
Not Provided
Principal Investigator: Mark Weiser, MD Sheba Medical Center
Sheba Medical Center
May 2012

ICMJE     Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP