PMH33 COST-EFFECTIVENESS OF ARIPIPRAZOLE FOR THE MANAGEMENT OF SCHIZOPHRENIA IN THE UNITED KINGDOM

Abstract

COST-EFFECTIVENESS OF ARIPIPRAZOLE FOR THE MANAGEMENT OF SCHIZOPHRENIA INTHE UNITED KINGDOM Davies A,Vardeva K, Loze JY, L’Italien GJ, Sennfalt K, Pugner K, van Baardewijk M Oxford Outcomes (UK), Oxford, England, Bristol-Myers Squibb, Uxbridge, UK, Otsuka Pharmaceutical France, Paris, France, Bristol-Myers Squibb,Wallingford, CT, USA, Bristol-Myers Squibb, Bromma, Sweden, Bristol-Myers Squibb, Braine l’Alleud, Belgium OBJECTIVE: To evaluate the cost-effectiveness of atypical antipsychotic treatment sequences for the management of stable schizophrenia in the UK. METHODS: A Markov model was developed to assess the cost per quality adjusted life year (QALY) gained from 12 alternative treatment sequences each containing two atypical antipsychotics (aripiprazole (ARI), olanzapine (OLZ), quetiapine (QTP), and risperidone (RSP)), followed by clozapine. The main model parameters were populated with data from the CATIE study, which provides a direct comparison of the effectiveness of OLZ, QTP and RSP, a recent trial of ARI compared with OLZ in the long-term treatment of schizophrenia, and a recent study of diabetes incidence in atypical treated patients. Patients enter the model with stable schizophrenia. On each treatment patients may relapse, discontinue, or continue and experience adverse events (extrapyramidal symptoms, weight gain, hyperprolactinemia), or develop diabetes. Population mortality was adjusted for schizophrenia and diabetes. Utility decrements applied to stable schizophrenia, relapse, diabetes, and treatment related adverse events were taken from a direct UK utility elicitation study. Dosing for OLZ, QTP, and RSP was based on CATIE. ARI is flat priced within the ranges of 5–15 mg and 20–30 mg; we assumed a simple average of these doses. Resource use and unit costs were taken from published sources. A time horizon of 10 years was adopted. RESULTS: ARI followed by RSP produced the greatest number of QALYs, an additional 0.03 compared to RSP followed by OLZ, at an incremental cost of £222 (incremental cost per QALY: £7942). ARI followed by RSP had the greatest probability among evaluated sequences of being cost effective at a threshold of £10,000 per QALY or higher. CONCLUSION: First-line atypical treatment with aripiprazole offers a cost-effective option for patients with stable schizophrenia.