Similar pharmacokinetics of three dosing regimens comprising two oral delayed-release mesalamine formulations in healthy adult volunteers: Randomised, open-label, parallel-group study

Br J Clin Pharmacol. 2021 Mar;87(3):1141-1149. doi: 10.1111/bcp.14479. Epub 2020 Aug 10.


Aims: Mesalamine is the first-line therapy for treating mild-to-moderate ulcerative colitis. Multiple mesalamine formulations are available, with similar safety and efficacy profiles. Mesalamine is commonly administered as divided dosing, although once-daily dosing may provide benefits for patients. We evaluated the pharmacokinetics of three dosing regimens of two oral delayed-release mesalamine formulations in healthy adult volunteers.

Methods: A randomised, open-label, parallel-group study of mesalamine pharmacokinetics following Lialda 2 × 1.2 g once daily (QD) (dose A), Asacol 6 × 400 mg QD (dose B), or Asacol 2 × 400 mg three times daily (TID) (dose C) over 7 days. Assessments included 5-aminosalicylic acid (5-ASA) and N-acetyl 5-aminosalicylic acid (N-Ac-5-ASA, primary metabolite) pharmacokinetics (Ae (%), AUC0-24 and Cmax ), safety and tolerability.

Results: All enrolled volunteers (n = 37) completed the study. Steady state was achieved for all treatments by day 4. Ratios (95% CI) of means for steady-state AUC0-24 (dose A vs B 90.3% [39.8, 204.8], dose A vs C 123.5% [55.3, 275.7], dose B vs C 136.8% [61.3, 305.5]) and Cmax (dose A vs B 106.0% [46.4, 242.2], dose A vs C 133.0% [59.1, 299.0], dose B vs C 125.5% [55.8, 282.1]) were similar for all 5-ASA treatments. Mean urinary excretion of 5-ASA plus N-Ac-5-ASA was comparable between treatments (dose A 21.3%, dose B 20.2%, dose C 17.9%). All treatment regimens were well tolerated; no safety issues were observed.

Conclusions: Plasma and urine pharmacokinetics for Asacol TID, Asacol QD, and Lialda QD are similar, suggesting similar daily systemic exposures can be obtained with either TID or QD dosing. NCT00751699.

Keywords: 5-ASA; Inflammatory bowel disease; clinical pharmacology.

Publication types

  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Administration, Oral
  • Adult
  • Anti-Inflammatory Agents, Non-Steroidal / adverse effects
  • Clinical Protocols
  • Colitis, Ulcerative* / drug therapy
  • Humans
  • Mesalamine* / adverse effects


  • Anti-Inflammatory Agents, Non-Steroidal
  • Mesalamine

Associated data