A randomized trial of Ustekinumab, a human interleukin-12/23 monoclonal antibody, in patients with moderate-to-severe Crohn's disease.

BACKGROUND & AIMS Interleukin-12 and interleukin-23 are inflammatory cytokines implicated in Crohn's disease pathophysiology. Ustekinumab is a monoclonal antibody against the p40 subunit of interleukin-12/23. METHODS We performed a double-blind, cross-over trial of the clinical effects of ustekinumab in 104 patients with moderate-to-severe Crohn's disease (population 1). Patients were given subcutaneous placebo at weeks 0-3, then ustekinumab at weeks 8-11; subcutaneous ustekinumab at weeks 0-3, then placebo at weeks 8-11; intravenous placebo at week 0, then ustekinumab at week 8; or intravenous ustekinumab at week 0, then placebo at week 8. Furthermore, an open-label trial evaluated the effects of 4 weekly subcutaneous injections or 1 intravenous infusion of ustekinumab in 27 patients who were primary or secondary nonresponders to infliximab (population 2). RESULTS In population 1, clinical response rates for the combined groups given ustekinumab and placebo were 53% and 30% (P = .02), respectively at weeks 4 and 6, and 49% and 40% (P = .34), respectively at week 8. In a subgroup of 49 patients who were previously given infliximab (neither primary nor secondary nonresponders), clinical response to ustekinumab was significantly greater than the group given placebo (P < .05) through week 8. In population 2, the clinical responses at week 8 to subcutaneous and intravenous ustekinumab were 43% and 54%, respectively. There was no increase in the number of adverse or serious adverse events in patients given ustekinumab through week 8 compared with placebo. CONCLUSIONS Ustekinumab induced a clinical response in patients with moderate-to-severe Crohn's disease, especially in patients previously given infliximab.