Xanomeline-trospium: advancing schizophrenia treatment beyond dopamine pathways

Background. Schizophrenia, a complex psychiatric disorder affecting approximately 1% of the global population, is characterized by a range of positive, negative, and cognitive symptoms. For decades, treatment has relied on dopamine receptor antagonists, which, while effective for positive symptoms, often have limited impact on negative and cognitive deficits and are associated with significant adverse effects. Objectives. This review aims to summarize the current evidence for xanomeline-trospium (Cobenfy), a first-in-class antipsychotic with a novel mechanism of action, in the treatment of schizophrenia in adults. We evaluate its mechanism, clinical efficacy, safety profile, and future prospects in the context of existing therapeutic options. Results. Xanomeline-trospium combines xanomeline, a muscarinic M1/M4 receptor agonist, with trospium, a peripherally restricted muscarinic antagonist that mitigates systemic cholinergic side effects. This combination targets the cholinergic system, bypassing the direct dopamine D2 receptor antagonism of conventional antipsychotics. Data from the pivotal EMERGENT clinical trial program (EMERGENT-1, -2, and -3) demonstrate both statistically significant and clinically meaningful improvements in Positive and Negative Syndrome Scale (PANSS) total scores compared to placebo. The treatment shows a favorable safety profile, with a low incidence of extrapyramidal symptoms, weight gain, and metabolic disturbances. Conclusions. With its novel mechanism of action and promising efficacy and tolerability data, xanomeline-trospium represents a significant advancement in the pharmacological management of schizophrenia. It has the potential to address unmet needs, particularly negative and cognitive symptoms, and may redefine the standard of care in psychiatric practice.