Felix-Martin Werner* and Rafael Coveñas Pages 1 - 6 ( 6 )
Background: Schizophrenia and schizoaffective disorder are treated with antipsychotic drugs. Some patients show treatment-resistant forms of psychotic disorders and, in this case, they can be treated with clozapine. In these patients and based on previous reviews on novel antipsychotic drugs, it is important to know whether an add-on therapy with new drugs can ameliorate the positive and negative schizophrenic scale (PANSS) total score.
Objective: The aim of this review is to suggest an appropriate treatment for patients with treatment-resistant forms of psychotic disorders. A combination of current available antipsychotic drugs with novel antipsychotic or modulating drugs might improve negative schizophrenic symptoms and cognitive function and thereby social functioning and quality of life.
Results: The mechanisms of action, the therapeutic effects and the pharmacokinetic profiles of novel antipsychotic drugs such as cariprazine, brexipiprazole and lumateperone are up-dated. Published case reports of patients with treatmentresistant psychoses are also discussed. These patients were treated with clozapine but a high PANSS total score was observed. Only an add-on therapy with cariprazine improved the score and, above all, negative schizophrenic symptoms and cognitive functions. To ensure a constant antipsychotic drug concentration, long-acting injectable antipsychotic drugs may be a choice for a maintenance therapy in schizophrenia. New modulating drugs, such as receptor positive allosteric modulators (N-methyl-D-aspartate receptor; subtype 5 of the metabotropic glutamatergic receptor) and encenicline, an alpha7 nicotinic cholinergic receptor agonist, are being investigated in preclinical and clinical trials.
Conclusion: In clinical trials, patients with treatment-resistant forms of psychosis should be examined to know whether a combination therapy with clozapine and a novel antipsychotic drug can ameliorate the PANSS total score. In schizophrenia, long-acting injectable antipsychotic drugs are a safe and tolerable maintenance therapy. In further clinical studies, it should be investigated whether patients with treatment-resistant forms of psychoses can improve negative schizophrenic symptoms and cognitive functions by an add-on therapy with cognition enhancing drugs.
Add-on therapy, antipsychotic drug, aripiprazole lauroxil, brexipiprazole, cariprazine, encenicline, long-acting injectable antipsychotic drug, NMDA receptor, paliperidone palmitate, PANSS total score
Höhere Berufsfachschule für Altenpflege und Ergotherapie der Euro Akademie Pößneck, Pößneck, Institute of Neurosciences of Castilla y León (INCYL), Laboratory of Neuroanatomy of the Peptidergic Systems, University of Salamanca, Salamanca