The cost-effectiveness of celecoxib versus non-steroidal anti-inflammatory drugs plus proton-pump inhibitors in the treatment of osteoarthritis in Saudi Arabia

Abstract

Background: Cyclooxygenase (COX)-2 inhibitors including celecoxib are as effective as non-selective non-steroidal anti-inflammatory drugs (ns-NSAIDs) in the treatment of osteoarthritis (OA) and have less gastrointestinal toxicity. Although they are associated with higher treatment costs, COX-2 inhibitors may simultaneously reduce costs associated with adverse events, hence, their overall economic benefit should be assessed. Objective: To evaluate the incremental cost effectiveness ratio (ICER) of celecoxib versus ns-NSAIDs, with/without proton-pump inhibitor (PPI) co-therapy, for managing OA in Saudi Arabian subjects aged ≥65 years. Methods: The National Institute for Health and Care Excellence health economic model from the UK, updated with relative risks of adverse events using CONDOR trial data, was adapted. Patients received celecoxib or ns-NSAIDs, with/without omeprazole. The effectiveness measure was quality-adjusted life years (QALYs) gained per patient. The analysis was conducted from the patient’s perspective. Frequencies of resource use for adverse events were based on data collected in July 2012 from seven private hospitals in Jeddah, Saudi Arabia. Probabilistic sensitivity analysis was performed to construct cost-effectiveness acceptability curves (CEACs). Results: Over a 6-month treatment duration, QALYs gained per patient were higher with celecoxib (0.37) and celecoxib plus PPI (0.40) versus comparators. Ibuprofen plus PPI showed the lowest expected cost per patient (US$ 1,314.50 versus US$ 1,422.80 with celecoxib plus PPI and US$ 1,543.50 with celecoxib). Celecoxib plus PPI was the most cost-effective option with an ICER of US$ 1,805.00, followed by celecoxib (ICER, US$ 7,633.33) versus ibuprofen plus PPI. Over 2- and 5-year treatment durations, celecoxib plus PPI, and celecoxib, showed higher QALYs gained/patient and lower ICERs versus comparators. These ICERs are <1 gross domestic product/capita in Saudi Arabia in 2013 (US$ 25,961). CEACs over 6 months’ treatment showed a significantly higher likelihood that celecoxib plus PPI and celecoxib alone would be more cost effective versus comparators once the willingness to pay is over US$ 2,000.00. Conclusion: After considering new adverse event risks, celecoxib with/without PPI co-therapy was deemed very cost effective for medium- and long-term use in Saudi Arabian OA patients aged ≥65 years.