Please use this identifier to cite or link to this item:
Scopus Web of Science® Altmetric
Type: Journal article
Title: N-acetylcysteine (NAC) in schizophrenia resistant to clozapine: a double blind randomised placebo controlled trial targeting negative symptoms
Author: Rossell, S.
Francis, P.
Galletly, C.
Harris, A.
Siskind, D.
Berk, M.
Bozaoglu, K.
Dark, F.
Dean, O.
Liu, D.
Meyer, D.
Neill, E.
Phillipou, A.
Sarris, J.
Castle, D.
Citation: BMC Psychiatry, 2016; 16(1):320-1-320-9
Publisher: BioMed Central
Issue Date: 2016
ISSN: 1471-244X
Statement of
Susan L. Rossell, Paul S. Francis, Cherrie Galletly, Anthony Harris, Dan Siskind, Michael Berk, Kiymet Bozaoglu, Frances Dark, Olivia Dean, Dennis Liu, Denny Meyer, Erica Neill, Andrea Phillipou, Jerome Sarris and David J. Castle
Abstract: Background: Clozapine is an effective treatment for a proportion of people with schizophrenia (SZ) who are resistant to the beneficial effects of other antipsychotic drugs. However, anything from 40–60 % of people on clozapine experience residual symptoms even on adequate doses of the medication, and thus could be considered ‘clozapine resistant’. Agents that could work alongside clozapine to improve efficacy whilst not increasing the adverse effect burden are both desired and necessary to improve the lives of individuals with clozapine-resistant SZ. N-Acetylcysteine (NAC) is one such possible agent. Previous research from our research group provided promising pilot data suggesting the efficacy of NAC in this patient population. The aim of the study reported here is to expand this work by conducting a large scale clinical trial of NAC in the treatment of clozapine-resistant SZ. Methods: This study is an investigator initiated, multi-site, randomised, placebo-controlled trial. It aims to include 168 patients with clozapine-resistant SZ, divided into an intervention group (NAC) and a control group (placebo). Participants in the intervention group will receive 2 g daily of NAC. The primary outcome measures will be the negative symptom scores of the Positive and Negative Syndrome Scale (PANSS). Secondary outcome measures will include: changes in quality of life (QoL) as measured by the Lancashire Quality of Life Profile (LQoLP) and cognitive functioning as measured by the total score on the MATRICS. Additionally we will examine peripheral and cortical glutathione (GSH) concentrations as process outcomes. Discussion: This large scale clinical trial will investigate the efficacy of NAC as an adjunctive medication to clozapine. This trial, if successful, will establish a cheap, safe and easy-to-use agent (NAC) as a ‘go to’ adjunct in patients that are only partly responsive to clozapine.
Keywords: N-Acetylcysteine; clozapine; schizophrenia; negative symptoms; cognition; biomarkers
Rights: © 2016 The Author(s). Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (, which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver ( applies to the data made available in this article, unless otherwise stated.
DOI: 10.1186/s12888-016-1030-3
Grant ID:
Appears in Collections:Aurora harvest 8
Medicine publications

Files in This Item:
File Description SizeFormat 
hdl_106183.pdfPublished version636.9 kBAdobe PDFView/Open

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.