Cost-effectiveness of etanercept in patients with severe ankylosing spondylitis in Germany

To estimate the cost-effectiveness of etanercept (ETN) plus usual care (including NSAIDs) compared with usual care alone (including NSAIDs) in patients with severe AS in Germany.

A mathematical model previously applied to the UK was adapted using resource use and cost data (for 2007) from the national database of the German Collaborative Arthritis Centres. Social health insurance (SHI) and societal perspectives were analysed. Assumptions on initial response and changes in health-related quality of life were based on Phase III randomized controlled trials. Initial treatment response according to British Society for Rheumatology guidelines were assumed as a conservative estimate in the German context. Long-term disease progression was based on the available literature. Incremental cost-effectiveness ratios (ICERs) were expressed as euros/quality-adjusted life year (QALY), for a cohort of 1000 patients over 25 years. Sensitivity analyses explored uncertainty in results.

In the base case, ETN plus usual care (including NSAIDs) yielded 1475 more QALYs at an additional cost of €80,827,668 (SHI) or €32,657,590 (societal) leading to an ICER of €54,815/QALY and €22,147/QALY, respectively. Over a shorter time horizon of 10 years, the ICERs were €59,006 and €29,815 for SHI and societal viewpoints, respectively. Assumptions having the largest impact on results included withdrawal rates from ETN, quality of life, disease costs and initial response.

Cost-effectiveness for ETN in patients with severe AS in Germany differs according to the cost perspective. Study estimates were higher than in the UK but comparable with reported cost-effectiveness of anti-TNF treatments in patients with RA in Germany.