Economic evaluation of etoricoxib versus non-selective NSAIDs in the treatment of osteoarthritis and rheumatoid arthritis patients in the UK.

INTRODUCTION: The objective of this study was to evaluate the potential economic implications of using etoricoxib versus non-selective NSAID alternatives in the treatment of patients with osteoarthritis (OA) or rheumatoid arthritis (RA) in the UK.

STUDY DESIGN: Decision-analytical modelling was used to calculate the expected costs and consequences of the use of etoricoxib compared with non-selective NSAIDs alone, NSAIDs plus proton pump inhibitors (PPIs), NSAIDs plus histamine H2 receptor antagonists and NSAIDs plus misoprostol over a continuous treatment period of 1 year.

METHODS: The model considered direct medical costs from the perspective of the UK National Health Service (NHS) and used data from phase IIb and III clinical trials of etoricoxib to determine probabilities of gastrointestinal (GI) events. Model outcomes were defined as resource-consuming GI-related events, including clinically evident gastroduodenal perforations, symptomatic gastroduodenal ulcers, or upper GI bleeding (collectively, PUBs ['perforation, ulcers and/or bleeding']). Resource utilisation and costs (2002 values) for the treatment of OA and RA as well as GI events were based on published literature and information available from UK-specific sources.

MAIN OUTCOME MEASURES AND RESULTS: The model suggests that etoricoxib is cost saving compared with non-selective NSAIDs plus PPIs or non-selective NSAIDs plus misoprostol. The model also suggests that etoricoxib is cost effective in terms of the incremental cost per QALY gained for non-selective NSAIDs alone (pound 19,766) and for non-selective NSAIDs plus H2 antagonists (pound 9350). The incremental cost of etoricoxib per PUB avoided was pound 12,446 versus non-selective NSAIDs alone and pound 6438 versus NSAIDs co-prescribed with H2 antagonists. For patients without the presence of specific GI risk factors (history of GI event, corticosteroid use or disability), etoricoxib may be cost effective for patients over age 56 years, assuming a cost-effectiveness threshold of pound 30,000 per QALY gained. Etoricoxib may also be cost effective in patients of all ages who had at least one specific GI risk factor.

CONCLUSIONS: The model suggests, with its underlying assumptions and data, that etoricoxib is a cost-effective alternative to therapeutic regimens involving non-selective NSAIDs for OA or RA, from the UK NHS perspective. Etoricoxib may be cost saving and dominant over non-selective NSAIDs used together with a PPI or misoprostol. When compared with non-selective NSAIDs alone or non-selective NSAIDs co-prescribed with H2 antagonists, the incremental cost per QALY gained with use of etoricoxib was within the generally accepted threshold for cost effectiveness (less than pound 30,000 per QALY gained).