OBJECTIVES

: To determine the cost-effectiveness of different long acting atypical anti-psychotic drugs namely paliperidone palmitate (PP-LAI), olanzapine pamoate (OLZ-LAI), and risperidone (RIS-LAI) to treat chronic schizophrenia from a payer’s perspective and to assess the budget impact of using antipsychotic LAI’s compared to oral antipsychotics using a payers’ perspective.

METHODS

: We developed a Markov Model to estimate the cost and QALY’s for different treatments for a cohort of patients with chronic schizophrenia. The model will be structured in terms of three health states: “stable”, “relapse” and “death”. Additionally, a budget impact analysis assessing the cost implications of using the three LAI’s in the health plan compared to the oral antipsychotics was conducted for a 1-year time frame. The model was built from a US payers’ perspective which only included direct medical costs such as acquisition costs of medication, hospitalization costs, outpatient cost and ER cost. Moreover, one-way sensitivity analyses were conducted to examine how changes in key model parameters affected the results. All cost and clinical parameters was discounted at an annual rate of 3%. The model was developed using the Tree Age software (© 2017 Tree Age Software Inc., Williamston, MA, USA).

RESULTS

: RIS-LAI was found to be the most dominant (i.e., less costly and more effective) with a $25,024/QALY gained at a WTP of $50,000. In the Budget Impact Model, the average cost saving associated with introduction of LAI’s in the formulary of the payer against oral atypical antipsychotics was US $964 per patient.

CONCLUSIONS

: RIS-LAI is estimated to provide both additional health benefits and cost savings compared to PP-LAI and OLZ-LAI. This budget impact analysis suggests that the adoption of LAI antipsychotics in schizophrenia patients will have a modest budget impact to the health plan.