OBJECTIVES: In November 2011, Center for Drug Evaluation completed the project which aimed to re-evaluate the currently reimbursed biologics for rheumatoid arthritis (RA), and to establish the evidence-based revision rules of reimbursed items covered by National Health Insurance (NHI). As part of the project, this study analyzed the NHI claim data to capture the utilization and prescription pattern of reimbursed biologics in adult patients. METHODS: Identity-encrypted claims data, including inpatient, ambulatory care and contracted pharmacies prescriptions, during 2001 to 2010 were utilized. All records with etanercept, adalimumab and rituximab were identified in the first step. Then the records were further separated into RA and non-RA usage, according to the diagnosis codes. Moreover, the RA patients who were newly treated with biologics were enrolled to assess long-term prescription pattern. We performed both Kaplan-Meier analyses to assess biologics switching over time and medication possession rates to evaluate medication compliance. RESULTS: The expenditure of biologics for RA patients increased rapidly in the past decade and came to NT$ 1.37 billion in 2010. Among 5,142 patients treated by biologics in 2010, 88% received etanercept or adalimumab, and 12% received rituximab. In prescription pattern analysis, rituximab was not reported due to lack of long-term data (reimbursed for RA since November 2008). A total of 3,928 and 1,508 patients initialed by etanercept and adalimumab were analyzed, separately. About 34% of etanercept subjects appeared switching over 85 months and 27% of adalimumab subjects applied second biologics over 45 months. The mean durations of continuous prescription were 29 months and 14 months, and the medication possession rates were 78% and 93%, respectively. CONCLUSIONS: Under current reimbursement rules, the persistence and compliance of biologic for RA patients were satisfactory. However, the increasing numbers of patients and biological alternatives might intensify the financial pressure on NHI.