A narrative review of non-racemic amisulpride (SEP-4199) for treatment of depressive symptoms in bipolar disorder and LB-102 for treatment of schizophrenia.

INTRODUCTION: The challenges posed by treatment-resistant schizophrenia and depressive symptoms have led to ongoing difficulties despite the availability of antipsychotics and antidepressants. This review addresses the potential of amisulpride analogs, particularly SEP-4199, in addressing these challenges through enhanced efficacy and reduced side effects. AREAS COVERED: This review focuses on the pharmacological profile of amisulpride analogs, exemplified by LB-102 and its derivative SEP-4199. PubMed gathered articles (up to 10 March 2023) on 'amisulpride,' 'schizophrenia,' 'bipolar disorder,' and 'major depressive disorder;' ClinicalTrials.gov tracked SEP-4199 and LB-102 trials. LB-102, a newly identified N-methylated analog of amisulpride, exhibits enhanced lipophilicity at lower doses, as demonstrated in a phase 1 study, indicating significant promise for therapeutic applications. The discovery of SEP-4199, a non-racemic analog composed of R- and S-enantiomers in an 85:15 ratio, is discussed, emphasizing its potential to enhance antidepressant effects while minimizing extrapyramidal side effects via selective D2 receptor binding. Recent phase 2 trials have demonstrated SEP-4199's efficacy in treating depressive symptoms in bipolar disorder I, capitalizing on D2-mediated anti-anhedonic and D3-mediated reward effects. EXPERT OPINION: The development of SEP-4199 presents a potential breakthrough for managing depressive symptoms in bipolar disorder I. Further exploration of D2 and D3 receptor-mediated effects could lead to improved treatment strategies.

The bidirectional association of nonalcoholic fatty liver disease with depression, bipolar disorder, and schizophrenia.

Nonalcoholic fatty liver disease (NAFLD) is a complex metabolic-inflammatory disease associated with poor outcomes and decreased quality of life. NAFLD is overrepresented in patients with psychiatric disorders like depression, bipolar disorder, and schizophrenia; however, a comprehensive review on NAFLD and psychiatric disorders remains to be delineated. This review endeavors to investigate the association of NAFLD with psychiatric disorders, including shared pathogenesis and future clinical derivatives. Extant literature suggests that patients with psychiatric disorders (in particular, mood disorders) are more susceptible to the development of NAFLD due to multiple reasons, including but not limited to hypothalamic-pituitary-adrenal axis dysregulation, metabolic syndrome, and chronic perceived stress. Moreover, the clinical manifestations of mood disorders (e.g., anhedonia, psychomotor retardation, lifestyle modification, etc.), and potentially long-term treatment with weight-gaining agents, differentially affect these patients, making them more prone to NAFLD. Considering the increased morbidity associated with both mood disorders and NAFLD, our review recommends regular screenings for NAFLD in select patients with mood disorders exhibiting signs of increased risk (i.e., obesity, metabolic syndrome, diabetes, or family history of NAFLD) for better diagnosis and holistic care of both potentially interrelated conditions.