Efficacy and safety of mirikizumab in patients with moderately-to-severely active Crohn's disease: a phase 3, multicentre, randomised, double-blind, placebo-controlled and active-controlled, treat-through study.

Background: Mirikizumab, a humanised monoclonal antibody that inhibits IL-23p19, is effective in moderate-to-severe ulcerative colitis. We aimed to evaluate the efficacy and safety of mirikizumab in patients with moderately-to-severely active Crohn's disease.

Methods: VIVID-1 was a global phase 3, randomised, double-blind, double-dummy, placebo-controlled and active-controlled, treat-through study.

Design considerations for two-stage enrichment clinical trials.

When there is a predictive biomarker, enrichment can focus the clinical trial on a benefiting subpopulation. We describe a two-stage enrichment design, in which the first stage is designed to efficiently estimate a threshold and the second stage is a "phase III-like" trial on the enriched population. The goal of this paper is to explore design issues: sample size in Stages 1 and 2, and re-estimation of the Stage 2 sample size following Stage 1.

Semiparametric analysis of zero-inflated recurrent events with a terminal event.

Recurrent event data frequently arise in longitudinal studies and observations on recurrent events could be terminated by a major failure event such as death. In many situations, there exist a large fraction of subjects without any recurrent events of interest. Among these subjects, some are unsusceptible to recurrent events, while others are susceptible but have no recurrent events being observed due to censoring.