An economic evaluation comparing once daily with twice daily mesalazine for maintaining remission based on results from a randomised controlled clinical trial

Background and aims: Standard practice to maintain remission in ulcerative colitis (UC) consists of daily mesalazine therapy. However, frequent dosing is associated with poor adherence and increased failure rates. The PODIUM (Pentasa (TM) Once Daily In UC Maintenance) randomised control trial showed 2 g once daily (OD) to be superior to twice daily (BD) dosing for maintaining remission. We sought to determine whether this alternative dosing regimen is cost-effective. Methods: An economic evaluation was conducted to compare costs and outcomes of OD with twice daily (BD) dosing. The main outcome considered was quality-adjusted life years (QALYs) based on health state utilities derived from the primary outcome measure, remission without relapse at 12 months defined by a UCDAI score <= 1. The economic evaluation consisted of two health states: (1) remission and (2) active UC. Results: Annual average treatment costs for OD and BD dosing were 654 pound (95% CI: 536- pound 759) pound and 747 pound (620- pound 860) pound, respectively with an average per person savings of 93 pound per year. Average annual costs of ancillary care for relapse for OD and BD dosing were 307 pound (241- pound 383) pound and 396 pound (320- pound 483) pound, respectively. Treatment with OD 2 g mesalazine resulted in an incremental QALY improvement of 0.004 units, indicating that it was the dominant treatment option (i.e. improved outcomes and cost-saving). Variations in parameter estimates in the sensitivity analysis indicated that mesalazine had > 0.95 probability of being cost-effective compared to BD based on accepted willingness to pay thresholds applied by the UK National Health Service. Conclusions: Once daily 2 g mesalazine for maintaining remission in UC is cost-saving compared with 1 g twice daily. Cost-savings with 2 g once daily were achieved by differences in ancillary care attributed to higher failure rates observed with 1 g twice daily. (c) 2008 European Crohn's and Colitis Organisation. Published by Elsevier B.V. All rights reserved.