Infliximab Induces Remission of Ulcerative Colitis

NEW YORK (Reuters Health) - Treatment of moderate-to-severe active ulcerative colitis, a severe inflammatory disease of the colon, with the drug infliximab is associated with sustained clinical responses and intestinal healing, according to results of two studies reported in The New England Journal of Medicine.

Infliximab, an antibody that binds to an inflammatory protein, is effective for treatment of Crohn's disease, Dr. William J. Sandborn, from Mayo Clinic in Rochester, Minnesota, and his co-investigators note. However, the drug's effectiveness for treating ulcerative colitis remains unknown. The Active Ulcerative Colitis Trials (ACT) 1 and 2 were designed to address this issue.

Both trials involved 364 patients who were randomly selected to receive intravenous inactive "placebo," infliximab 5 milligram/kilogram or infliximab 10 milligram/kilogram. Treatment was given at the beginning of the study, at weeks 2 and 6, and then every 8 weeks through week 46 (in ACT 1) or week 22 (in ACT 2).

In both studies, the authors report, the proportion of patients who had a clinical response or remission was higher in the infliximab groups than in the placebo groups.

For example, in ACT 1 at week eight, 70 percent of those receiving 5 milligram/kilogram infliximab and 62 percent of those receiving 10 milligram/kilogram had a clinical response, compared with 37 percent of those in the placebo group. In ACT 2, corresponding rates were 65, 70 and 29 percent.

Improvement in symptoms was noted as early as the second week, and did not depend on whether patients responded to steroid treatment or not. More patients in the infliximab groups were able to discontinue steroid treatment.

Rates of side effects were similar in the treatment groups, although the number of serious infections, lupus-like reactions, and neurologic complications was slightly higher in the infliximab groups.

However, Sandborn's team points out, infliximab risk must be weighed against the risk of colon removal to treat ulcerative colitis and its potential complications.

SOURCE: The New England Journal of Medicine, December 8, 2005.