Cost-Utility Analysis of Aripiprazole, Olanzapine Branded Generic, and Olanzapine Generic on Stable Phase of Schizophrenia Patient at Mental Health Hospital in Jakarta

OBJECTIVES: The study aimed to determine the cost-utility of aripiprazole (ARI), olanzapine branded generic (Olan-BG), and olanzapine INN generic (Olan-IG) in schizophrenia patients.

METHODS: The study was designed as a cohort to observe patients with schizophrenia at a stable phase from the initial therapy until the patients discharge from the mental health hospital in Jakarta. The study perspective was payer. Data were obtained prospectively from medical records, the EQ-5D-5L Questionnaire, and the finance department to collect the direct medical costs. The EQ5D-5L Questionnaire was filled twice by nurses during the initial treatment and before the patient discharge from the hospital. Study parameters were: Length of Stay (LOS) and Utility scores. Kruskal Wallis statistical test was conducted to determine the difference in the treatment outcomes and cost.

RESULTS: We observed 206 patients, consisting of three groups: ARI= 30 patients, Olan-BG= 114 patients, and Olan-IG= 62 patients. The average direct medical cost per patient of ARI was IDR 1,748,652, (USD 123,36) and Olan-BG IDR 1,718,436.68 (USD 121,23) which was higher than the Olan-IG cost IDR 1,430,129.79 (USD 100,89). The LOS did not show significant differences, ARI vs. Olan-BG vs. Olan-IG were 11,43 days vs. 12,40 days vs. 11,7 days, respectively (P-value=0,090). The increase of utility scores from initial therapy until discharge from the hospital showed a significant difference, ARI vs. Olan-BG vs. Olan-IG were 0.193 vs. 0.186 vs. 0.249, respectively (P-value=0.002). The average cost-utility ratio for Ari vs. Olan-BG vs. Olan-IG was 639.17 vs. 651.77 vs. 405.18.

CONCLUSIONS: Olanzapine-IG had a low cost and provided a higher utility than aripiprazole or olanzapine-BG.