To assess cost-effectiveness of abatacept in patients with moderately to severely active RA and inadequate response to MTX.
We developed a simulation model to depict progression of disability [in terms of the HAQ Disability Index (HAQ-DI)] in women aged 55-64 yrs with moderately to severely active RA and inadequate response to MTX. At model entry, patients were assumed to receive either only MTX or MTX plus abatacept. Patients were then tracked from model entry until death. Future health-state utilities and medical-care costs (except study therapy) were estimated based on predicted values of the HAQ-DI. The model was estimated using data from a Phase III clinical trial of abatacept plus various secondary sources. Cost-effectiveness was expressed in terms of incremental cost (2006 US$) per quality-adjusted life-year (QALY) gained over alternatively 10 yrs and a lifetime. Costs and health effects were both discounted at 3% annually.
Over 10 yrs, abatacept would yield 1.2 additional QALYs (undiscounted) per patient (4.6 vs 3.4 for MTX) at an incremental (discounted) cost of $51,426 ($103,601 vs $52,175, respectively); over a lifetime, corresponding figures were 2.0 QALYS (6.8 vs 4.8) and $67,757 ($147,853 vs $80,096). Cost-effectiveness was [mean (95% CI)] $47,910 ($44,641, $52,136) per QALY gained over 10 yrs and $43,041 ($39,070, $46,725) per QALY gained over a lifetime. Findings were robust in sensitivity analyses.
Abatacept is cost-effective by current standards of medical practice in patients with moderately to severely active RA and inadequate response to MTX.