Novel Candidate Genes for Treatment Response to Antipsychotics in Schizophrenia: Evidence From Pharmacogenetics in the Light of Personalized Medicine

Schizophrenia is a severe and chronic mental disorder. The lifetime risk of schizophrenia is around 1%. Its course is chronic and frequently disabling. The keystone of schizophrenia treatment is antipsychotic medications. The use of antipsychotics represents a huge public health and economic burden to society. Most of antipsychotics drugs are "metoo" drugs, directly or indirectly replicating dopamine D2 receptor blockade. Pharmaceutical companies have aimed to produce drugs with a general indication for all patients with schizophrenia with a "one-size-fits-all" strategy with no targeting or stratification. Second generation antipsychotics partly improve positive symptoms and are quite often associated to weight gain, metabolic changes and increased risk of cardiovascular diseases. Antipsychotics only achieve a certain degree of clinical improvement in a percentage of patients (45%) and 30% of the patients are treatment resistant. In light of the current deadlock, there is an urgent need to expand the horizon of pharmacological research by elucidating new mechanisms related to antipsychotic actions. An alternative strategy is the comparison of gene expression profiles in drug-naive accurately ill patients before and after antipsychotic treatment has been initiated. Our research group has a great experience in the field and has been working on this hypothesis in the latest years. We propose a continuation project to thoroughly explore the clinical implications (clinical response to antipsychotic drugs or emergence of metabolic side effects) of the variants in gene expression we have recently described in schizophrenia patients. This project takes advantage of an exceptional (regarding to the detailed knowledge of clinical outcome and side effect profile) longitudinal cohort of drug-naive patients with schizophrenia who had been followed up for three years at the University Hospital Marqués de Valdecilla.