A treatment of psychosis based on biomarkers
18 November 2017
The Centre of Psychiatric Neurosciences (CNP) schizophrenia research Unit (Prof. Kim Do Cuénod) and the CHUV General Psychiatry Department (Prof. Philippe Conus), in partnership with the Harvard Medical School of Boston (Prof. Larry Seidman), have conducted a clinical trial with N-acetyl-cysteine (NAC) in patients who have recently developed psychosis.
Their results were published in the journal “Schizophrenia Bulletin“.
NAC, an anti-oxidant substance with no side effects used clinically for various indications, is also a precursor of glutathione, one of the most important brain antioxidants, whose metabolism is disrupted in patients. A study, conducted a few years ago by the same group in patients suffering from chronic schizophrenia, had shown that the addition of NAC to the usual neuroleptic treatment had a beneficial effect on certain symptoms of the disease (deficits of communication, expression of emotions and socialization) and also improved auditory signal processing and neuronal synchronization, assessed through the electroencephalogram.
With this in mind, this group began in 2009 the study of the impact of the addition of NAC in patients passing through the earlier stages of the disease. In this clinical trial, young patients who had recently developed a psychosis received, in addition to standard neuroleptic treatment, either NAC or placebo, for a duration of 6 months. The results of this study, published in the October issue of the journal ‘Schizophrenia Bulletin’, show that:
- Administration of oral NAC leads to an increase in cerebral glutathione, a molecule that protects brain cells from oxidation;
- The administration of NAC improves cognitive functions, especially the speed of information processing. This result is particularly promising if we consider that cognitive disorders are common in these patients, that they are one of the main determinants of social integration and that there is currently no effective drug in this area;
- Finally, the evaluation in the blood of the cellular oxidation state makes it possible to identify a subgroup of patients in “high oxidation state” in which the addition of NAC allows a significant improvement of symptoms such as hallucinations, delusions or disorganization of thoughts. In addition, the decrease in symptoms seems to be even more marked that the oxidation state is normalized in the blood.
These results, which need to be confirmed on a larger scale, open the door to an innovative treatment, based on neuro-protection and guided by the measurement of biomarkers of psychosis. It is indeed a first step towards personalized treatment, whose indication can be defined on the basis of a biological marker, and whose effectiveness can also be measured biologically, which is a first in the field of psychiatry.
Author : Virginie Bovet Remund, Communication Dept./CHUV article (FR) >
Translation : Tania Secalin
Philippe Conus Larry J Seidman Margot Fournier Lijing Xin Martine Cleusix Philipp S Baumann Carina Ferrari Ann Cousins Luis Alameda Mehdi Gholam-Rezaee Philippe Golay Raoul Jenni T.-U. Wilson Woo Matcheri S Keshavan Chin B Eap Joanne Wojcik Michel Cuenod Thierry Buclin Rolf Gruetter Kim Q Do;
N-acetylcysteine in a double-blind randomized placebo-controlled trial: Toward biomarker-guided treatment in early psychosis.
Schizophrenia Bulletin, sbx093, Oct 2017. doi.org/10.1093/schbul/sbx093 >