Estimated medical cost reductions for paliperidone palmitate vs placebo in a randomized, double-blind relapse-prevention trial of patients with schizoaffective disorder

Abstract

Objective:

The objective of this economic model was to estimate the difference in medical costs among patients treated with paliperidone palmitate once-monthly injectable antipsychotic (PP1M) vs placebo, based on clinical event rates reported in the 15-month randomized, double-blind, placebo-controlled, parallel-group study of paliperidone palmitate evaluating time to relapse in subjects with schizoaffective disorder.

Research design and methods:

Rates of psychotic, depressive, and/or manic relapses and serious and non-serious treatment-emergent adverse events (TEAEs) were obtained from the long-term paliperidone palmitate vs placebo relapse prevention study. The total annual medical cost for a relapse from a US payer perspective was obtained from published literature and the costs for serious and non-serious TEAEs were based on Common Procedure Terminology codes. Total annual medical cost differences for patients treated with PP1M vs placebo were then estimated. Additionally, one-way and Monte Carlo sensitivity analyses were conducted.

Results:

Lower rates of relapse (−18.3%) and serious TEAEs (−3.9%) were associated with use of PP1M vs placebo as reported in the long-term paliperidone palmitate vs placebo relapse prevention study. As a result of the reduction in these clinical event rates, the total annual medical cost was reduced by $7140 per patient treated with PP1M vs placebo. One-way sensitivity analysis showed that variations in relapse rates had the greatest impact on the estimated medical cost differences (range: −$9786, −$4670). Of the 10,000 random cycles of Monte Carlo simulations, 100% showed a medical cost difference <$0 (reduction) for patients using PPIM vs placebo. The average total annual medical differences per patient were −$8321 for PP1M monotherapy and −$6031 for PPIM adjunctive therapy.

Conclusions:

Use of PP1M for treatment of patients with schizoaffective disorder was associated with a significantly lower rate of relapse and a reduction in medical costs compared to placebo. Further evaluation in the real-world setting is warranted.

Keywords::

• Schizoaffective disorder
• Paliperidone palmitate
• Economic model
• Medical costs

Transparency

Declaration of funding

This research and preparation of this manuscript was supported by Janssen Scientific Affairs.

Declaration of financial/other relationships

KJ and DJF are employees of Janssen Scientific Affairs and own stock in the company. JL and MLS are employees of Novosys Health, which has received research funds from Janssen Scientific Affairs in connection with conducting this study and development of this manuscript. JME peer reviewers on this manuscript have no relevant financial or other relationships to disclose.