The impact of introducing biologics to patients with rheumatoid arthritis in Taiwan: a population-based trend study

The biologics used to treat rheumatoid arthritis (RA) patients with a catastrophic illness certificate have been free without co-payment since 2003 in Taiwan. The purpose of this study was to explore the trend of health care expenditures and the cost of biologics for the treatment of RA patients between 1999 and 2009.

This study used a specially requested nation-wide RA patient claim dataset from National Health Insurance program. We identified all patients by both the primary diagnosis code ICD-9-CM 714.0 and the catastrophic illness certificate for RA. A total of 30 013 patients were recorded in the treated RA cohort from 1999 to 2009.The growth rates before and after introducing biologics were compared and tested.

We found that from 1999 to 2009 the adjusted incidence rate for RA stably increased. Drug costs accounted for 53.2-70.3% of the total medical cost during the study period. There was a significant increase in biologics cost, climbing rapidly from 2.8% in 2003 to 60.4% of the total drug cost in 2009. The growth rate of outpatient drug costs was much higher after the introduction of biologics (2003-2009), which was 207.8% versus 42.0% as compared to the earlier period (1999-2002). Biologics such as etanercept, adalimumab and rituximab, were the crucial factors responsible for this increase in drug cost.

The financial impact of adopting new biologics on healthcare costs is a critical issue that needs to be addressed by the National Health Insurance.