Aminosalicylates in Crohn's disease

Aminosalicylate drugs, particularly mesalazine, may be used for the induction and maintenance of remission in Crohn's disease.

• efficacy of aminosalicylates is small, especially if disease is limited to the ileum
• meta-analysis indicates that aminosalicylates probably only reduce the risk of relapse by about 1/3 in contrast to the 2/3 reduction in relapse rate that is seen with maintenance therapy with aminosalicylates in UC
• patients who relapse on aminosalicylates will need steroid treatment
• the clinical effect of this class of agent is mediated by inhibiting multiple mediators of inflammation, including cytokines, platelet activating factor and possibly leukotriene B4

European evidence-based consensus group and a Cochrane systematic review haven’t found any evidence that aminosalicylates (such as mesalazine) are superior to placebo at maintaining remission in people with medically-induced remission of Crohn’s disease (1).

Mesalazine has been found to reduce relapses after surgery (especially after small bowel resection) (2).

NICE state (3):

• inducing remission in Crohn's disease
  • use of 5-ASA for inducing remission in Crohn's disease
    • in people who decline, cannot tolerate or in whom glucocorticosteroid treatment is contraindicated, consider 5-aminosalicylate (5-ASA) treatment for a first presentation or a single inflammatory exacerbation in a 12-month period. Explain that aminosalicylates are less effective than a conventional glucocorticosteroid or budesonide but may have fewer side effects than a conventional glucocorticosteroid.
      
      
• maintaining remission in Crohn's disease after surgery
  • consider 5-ASA treatment to maintain remission after surgery

Reference:

• (1) Akobeng AK, Gardener E. Oral 5-aminosalicylic acid for maintenance of medically-induced remission in Crohn's Disease. Cochrane Database Syst Rev. 2005;(1):CD003715
• (2) Carter MJ et al. Guidelines for the management of inflammatory bowel disease in adults. Gut. 2004;53 Suppl 5:V1-16
• (3) NICE. Crohn’s disease: management. NICE guideline NG129. Published May 2019