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™ 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 (95% CI: £536-£759) and £747 (£620-£860), respectively with an average per person savings of £93 per year. Average annual costs of ancillary care for relapse for OD and BD dosing were £307 (£241-£383) and £396 (£320-£483), 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.