Efficacy and tolerability of co-administration of clozapine with atypical antipsychotics in patients with treatment-resistant schizophrenia, comorbid with chemical addictions

Objective

To compare the efficacy and tolerability of combination therapy with clozapine and atypical antipsychotics for patients with treatment-resistant schizophrenia, comorbid with chemical addictions. Material and methods: A clinical study was conducted from 2018 to 2026 in various psychiatric departments in the North-Western, Siberian, and Ural regions of the Russian Federation. The study included a total of 470 male and female participants diagnosed with therapeutically resistant paranoid schizophrenia, comprising individuals with and without concomitant chemical addictions: n=80 without addictions; n=390 with unrelated chemical addictions (opioid, cannabinoid, psychostimulant, and ethanol dependence). Participants were randomly allocated into six treatment groups receiving distinct combinations of medications: clozapine with cariprazine (n=84), lurasidone (n=84), aripiprazole (n=78), risperidone (n=84), olanzapine (n=70), or brexpiprazole (n=70). The clinical status of patients was assessed at weeks 2 and 6 of the therapeutic regimen.