Presentation (CTI)

OBJECTIVES: Schizophrenia is a chronic psychiatric disorder that is among the top 10 leading causes of disability globally. The standard of care (SOC) primarily targets psychotic symptoms but has limited efficacy towards negative and cognitive symptoms, underscoring the unmet need for new therapies that leverage novel mechanisms of action. Xanomeline and trospium chloride, which acts on the muscarinic receptors, offers a distinct approach compared to SOC. In this cost-effectiveness analysis, we aimed to evaluate the cost-effectiveness of xanomeline and trospium chloride compared to aripiprazole, an atypical antipsychotic. Aripiprazole was chosen based on findings demonstrating it has the fewest side effects among the medications within the drug class.
METHODS: We developed a lifetime Markov model from a U.S. healthcare perspective in Excel that simulated a cohort of adults with schizophrenia during the maintenance period and recorded treatment-emergent adverse events, treatment switching, treatment discontinuation, and death over three-month cycles. The model derived input parameters from published sources and calculated quality-adjusted life years (QALYs) gained, costs associated with both treatment strategies, and expressed cost-effectiveness as an incremental cost-effectiveness ratio (ICER). A one-way sensitivity analysis was performed to assess the uncertainty in model parameters.
RESULTS: Compared to aripiprazole, xanomeline and trospium chloride increased lifetime QALYs by 0.10, costs by $71,228, and yielded an ICER of $727,796/QALY gained. We found that the parameters most sensitive to changes in the one-way sensitivity analysis were utility in stable schizophrenia with no adverse events and utility in those with schizophrenia & metabolic syndrome.
CONCLUSIONS: Our findings suggest that xanomeline and trospium chloride is not cost-effective as maintenance treatment for schizophrenia in the U.S. We found that xanomeline and trospium chloride would be cost-effective at $150,000/QALY if the total healthcare costs for a three-month cycle did not exceed $5,950.