Delayed-release oral mesalamine at 4.8 g/day (800 mg tablet) for the treatment of moderately active ulcerative colitis: the ASCEND II trial

Am J Gastroenterol. 2005 Nov;100(11):2478-85. doi: 10.1111/j.1572-0241.2005.00248.x.


Background and aims: Preliminary data have shown that delayed release oral mesalamine (Asacol) dosed at 4.8 g/day provided additional efficacy benefit compared to 1.6 g/day in patients with mildly to moderately active ulcerative colitis. Additionally, Asacol dosed at 2.4 g/day has been proved to be more effective than 1.6 g/day. Whether 4.8 g/day of mesalamine (dosed with an investigational 800 mg tablet) is more effective than Asacol 2.4 g/day (dosed with a 400 mg tablet) in patients with moderately active ulcerative colitis is unknown.

Methods: A randomized, double-blind, controlled trial (ASCEND II) was conducted to evaluate the efficacy of 4.8 g/day of mesalamine in adults with active ulcerative colitis. Three hundred eighty-six patients with mild to moderate ulcerative colitis were randomized for treatment with mesalamine 2.4 g/day (400 mg tablet) or 4.8 g/day (800 mg tablet) for 6 wk. The primary efficacy population was 268 patients with moderately active ulcerative colitis treated with 2.4 g/day (n = 139) or 4.8 g/day (n = 129). The primary endpoint was the proportion of patients in each treatment group that achieved overall improvement ("treatment success," defined as either complete remission or a clinical response to therapy) from baseline at week 6.

Results: Seventy-two percent of patients receiving 4.8 g/day of mesalamine for moderate ulcerative colitis (89/124 patients) achieved treatment success at week 6, compared with 59% of those who received 2.4 g/day (77/130 patients) (p= 0.036). Both regimens were well tolerated. Adverse events and clinically significant changes in laboratory results were similar in both treatment groups.

Conclusions: Patients with moderately active ulcerative colitis treated with 4.8 g/day of mesalamine (800 mg tablet) are significantly more likely to achieve overall improvement at 6 wk compared to patients treated with 2.4 g/day.

Publication types

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

MeSH terms

  • Administration, Oral
  • Adolescent
  • Adult
  • Aged
  • Anti-Inflammatory Agents, Non-Steroidal / administration & dosage*
  • Anti-Inflammatory Agents, Non-Steroidal / adverse effects
  • Anti-Inflammatory Agents, Non-Steroidal / blood
  • Colitis, Ulcerative / classification
  • Colitis, Ulcerative / drug therapy*
  • Delayed-Action Preparations
  • Double-Blind Method
  • Female
  • Follow-Up Studies
  • Humans
  • Male
  • Mesalamine / administration & dosage*
  • Mesalamine / adverse effects
  • Mesalamine / blood
  • Middle Aged
  • Placebos
  • Recurrence
  • Remission Induction
  • Safety
  • Treatment Outcome


  • Anti-Inflammatory Agents, Non-Steroidal
  • Delayed-Action Preparations
  • Placebos
  • Mesalamine