Using Cariprazine to Ameliorate Negative Symptoms and Metabolic Side Effects of Clozapine and Paliperidone - Clinical Cases

A review on the pharmacology of cariprazine and its role in the treatment of negative symptoms of schizophrenia

Management of negative symptoms is one of the most challenging and important unmet needs of schizophrenia treatment. Negative symptoms together with positive symptoms result in significant psychosocial impairment and poor quality of life. Existing studies on atypical antipsychotics reported limited treatment adherence due to higher prevalence of treatment-emergent adverse events, such as diabetes, weight gain, hyperlipidemia, hyperprolactinemia and hypertension. A compound with greater affinity for dopamine D2/D3 receptors may improve negative symptoms, mood, and cognitive impairment associated with schizophrenia. In 2015, the US FDA has approved cariprazine, a partial D2/D3 agonist for treatment of schizophrenia, mania or mixed episodes. Midlands and Lancashire Commissioning Support Unit, UK (2019) has particularly suggested cariprazine for the treatment of predominant negative symptoms of schizophrenia. India's Central Drugs Standard Control Organization (CDSCO) has approved cariprazine in 2021 for the treatment of schizophrenia, manic or mixed episodes associated with bipolar I disorder. A ten-fold greater affinity for D3 receptors and partial agonism to serotonin receptors, along with longer half-life make cariprazine distinct when compared with other atypical antipsychotics. Cariprazine is also reported to have fewer incidents of metabolic and hormonal adverse events, and has been shown to provide better relapse prevention. Recent evidence indicates promising effect of cariprazine in ameliorating negative symptoms as well as psychotic symptoms in patients with schizophrenia. In addition, improved adherence to treatment (adjunctive/monotherapy) with cariprazine in patients having inadequate response to an ongoing antipsychotic treatment has also been clinically established. This review presents the evidence-based safety and efficacy of cariprazine for treatment of predominant negative symptoms of schizophrenia.

Efficacy, safety, and tolerability of ulotaront (SEP-363856, a trace amine-associated receptor 1 agonist) for the treatment of schizophrenia and other mental disorders with similar pathophysiology: a systematic review of preclinical and clinical trials

INTRODUCTION

Schizophrenia is a mental illness that can disrupt emotions, perceptions, cognition, and reduce quality of life. The classical approach to treat schizophrenia uses typical and atypical antipsychotics; however, limitations include low efficacy in mitigating negative symptoms and cognitive dysfunctions, and a range of adverse effects. Evidence has accumulated on trace amine-associated receptor 1 (TAAR1) as a novel therapeutic target for treating schizophrenia. This systematic review investigates the available evidence on a TAAR1 agonist, ulotaront, as a treatment for schizophrenia.

METHODS

A systematic search was conducted on PubMed/MEDLINE, and Ovid databases for English-published articles from inception to December 18, 2022. Literature focusing on the association between ulotaront and schizophrenia were evaluated based on an inclusion/exclusion criterion. Selected studies were assessed for risk of bias, using Cochrane Collaboration tool, and summarized in a table to generate discussion topics.

RESULTS

Three clinical, two comparative, and five preclinical studies examining ulotaront's pharmacology, tolerability and safety, and/or efficacy were identified. Results indicate that ulotaront has a differing adverse effects profile from other antipsychotics, may mitigate metabolic-related adverse effects commonly associated with antipsychotics, and may be effective for treating positive and negative symptoms.

CONCLUSIONS

Findings from available literature present ulotaront as a potential and promising alternative treatment method for schizophrenia. Despite this, our results were limited due to lack of clinical trials on ulotaront's long-term efficacy and mechanisms of action. Future research should focus on these limitations to elucidate ulotaront's efficacy and safety for the treatment of schizophrenia and other mental disorders with similar pathophysiology.