There are six modified-release preparations of mesalazine currently licensed in the UK. In this paper in the British Journal of Clinical Pharmacy, the North Central London Formulary and Medicines Management Group propose a prescribing strategy for these preparations that could potentially save the NHS several million pounds over the next five years.

The authors discuss the licensing of a generic product, comparative studies, prescribing and cost issues. They note “on the basis of 2008/09 prescribing figures for England, we estimate that a substitution of Mesren MR for Asacol MR in patients with stable ulcerative colitis, and for those newly started on 5-aminosalicylate therapy, has the potential to save £20m in primary care prescribing costs over the next five years.”

The following pragmatic approach in achieving a successful therapeutic rationalisation of these formulations is proposed:

• Mesren MR should be prescribed instead of Asacol MR for all new patients, and for patients who require a change to their drug regimen. Discretion should be applied in switching patients to Mesren MR who have mild and/or stable ulcerative colitis.

• Mezavant XL should only be considered for select patients experiencing difficulty with a high pill burden (i.e. >2.4g/daily), since it has a convenient once-daily dosing advantage. Since Mezavant XL is almost twice the cost of Mesren MR, at the point of maintenance dose prescribing (i.e. ≤2.4g/daily), Mesren MR should be substituted.