Mesalazine

Additional information

Mesalazine is known as mesalamine in English literature . Mesalamine belongs to the 5-ASA group and is used in inflammatory bowel disease.

Pharmacokinetics and dosing

No studies with a clinically relevant sex analysis regarding the pharmacokinetics of mesalamine have been found.One small study (3 men, 5 women) of 60 ml mesalamine found that the local distribution was similar in all patients after anal administration [1]. No other studies with a clinically relevant sex analysis regarding the dosing of mesalamine have been found.

Effects

Response to mesalamine in patients with Crohn disease has retrospectively been assessed in a register-based cohort study (71 men, 94 women). Women were more likely than men to achieve prolonged response or develop mesalamine dependency (68% vs. 51%, odds ratio 2.89). Prolonged response was defined as still in complete/partial response one year after induction of response. Mesalamine dependency was defined as relapse within 1 year after mesalamine discontinuation and regaining complete/partial response after mesalamine re-introduction [2].

In patients with ulcerative colitis, studies of mesalamine efficacy show different results whether treatment success is different in men and women. A randomized, double-blind, placebo-controlled clinical trial of mesalamine efficacy in patients with ulcerative colitis, showed that patient’s sex did not predict treatment success. Success was defined as maintenance of remission at 6 months, while failure was defined as relapse at any time during the study or withdrawal due to an adverse event [3]. On the other hand, a study of patients with ulcerative colitis treated with mesalamine after a pre- treatment with corticosteroids (19 men, 16 women), showed that the probability of relapse at 1 year was higher in men than in women (hazard ratio 4) [4]. The authors suggest that the higher risk of relapse in men might be explained by poor adherence (see Other information).

Adverse effects

A register-based study has analyzed if long-term use of mesalamine, olsalazine or sulfasalazine reduces the risk of colorectal cancer in patients with inflammatory bowel disease. An increased risk in men was seen among patients who used mesalamine, olsalazine or sulfasalazine for at least 1 year (hazard ratio 1.56). However after at least 5 years the sex difference was only significant for patients with ulcerative colitis (hazard ratio 1.59). After 7.5 years of use, there was no sex difference in risk [5].

Reproductive health issues

Regarding teratogenic aspects, please consult Janusmed Drugs and Birth Defects (in Swedish, Janusmed fosterpåverkan).

Other information

Adherence to medications in patients with ulcerative colitis has varied in men and women in different studies. In one study, where patients received sulfasalazine, mesalamine, olsalazine, or balsalazide (51 men, 43 women), men were twice as likely as women to be non-adherent (odds ratio 2.1) [6]. Contrary to these findings, studies have shown that women with ulcerative colitis were more likely than men to be non-adherent. [7-9]. Furthermore, another study found that patient’s sex did not predict adherence to mesalamine in inflammatory bowel disease [10].