IntroductionAlthough antipsychotic medications have been a cornerstone in the treatment of schizophrenia for decades worldwide, the orally disintegrating tablet (ODT) formulation is a new concept in China. Only four brand names exist in the Chinese market, three of which were launched recently. Patients taking ODTs have a higher rate of medication adherence and consequently experience better treatment outcomes than patients taking the same medication in standard oral tablet (SOT) formulation. This study aimed to analyze the cost effectiveness in China of aripiprazole in ODT form, compared with the SOT forms of aripiprazole and olanzapine.
MethodsA discrete-event simulation model was built to represent the one-year progression of schizophrenia. On entry into the model, 100,000 people for each treatment arm were labeled fully adherent, partially adherent, or non-adherent based on medication possession ratios, and then experienced events including relapse, adverse events, changing adherence levels, and treatment switching and quitting. Parameters for adherence rates, medical costs, and utility values were derived from the published literature. The switching pattern was acquired through interviews with fifty-seven Chinese psychiatrists.
ResultsThe total annual costs per patient in the aripiprazole-ODT, aripiprazole-SOT, and olanzapine-SOT arms were CNY 9,817 (USD 1,388), CNY 15,278 (USD 2,160), and CNY 10,298 (USD 1,456), respectively. The annual quality-adjusted life-years (QALYs) gained per patient in the aripiprazole-ODT, aripiprazole-SOT, and olanzapine-SOT arms were 0.73, 0.71, and 0.72, respectively. According to the probabilistic sensitivity analysis, the probability of aripiprazole-ODT being cost effective was ninety-nine percent, when compared with aripiprazole-SOT and sixty-nine percent when compared with olanzapine-SOT.
ConclusionsAripiprazole-ODT was associated with lower costs and higher gains in QALYs than either aripiprazole-SOT or olanzapine-SOT in patients with schizophrenia in China. While the sensitivity analysis confirmed the robustness of the result that aripiprazole-ODT was better economic value than aripiprazole-SOT, there is some uncertainty in the comparison between aripiprazole-ODT and olanzapine-SOT. The main limitation of this study is that some parameters were sourced from studies on Western populations because of a lack of data in China. Local data on the use of antipsychotics, especially adherence rates, is needed.