A141 DIFFERENT INDUCTION RESPONSE CRITERIA DO NOT INFLUENCE 1 YEAR RESPONSE AND REMISSION RATES OF USTEKINUMAB 90MG Q8W IN PHASE III PROGRAM. (1st March 2018) - Naessens, D
Abstract: Background: Crohn's disease Phase III maintenance clinical trials with biologics are typically randomized withdrawal trials, in which patients (pts) that responded after induction with a specific biologic are re-randomized to either maintenance therapy or placebo (PBO). Different response criteria have been used to qualify responders for these studies, such as CDAI70 at wk 2, 4 or 6 & CDAI 100 at wk8, but the influence of this criterion on remission results at year 1 has not been investigated. Aims: In the IM-UNITI study, pts with a CDAI 100 response 8wks after ustekinumab (UST) induction were re-randomized to either PBO, UST 90mg Q12w or UST 90mg Q8w. Non-responders to UST induction, as well pts that received PBO for induction remained blinded in the trial. Non-responders to UST induction received UST 90mg SC Q8w at wk0 of IM-UNITI. Since both UST CDAI-100 responders & non-responders received 90mg Q8w, remission rates at 52wks of total treatment can be calculated for UST 90mg Q8w for pts with different induction response criteria. Methods: Pre-specified analyses were conducted to evaluate the proportion of pts in remission & CDAI-100 response at 52wks of total treatment in the different arms of IM-UNITI for pts with a 70 point CDAI response to UST at wk6 of induction.70 point CDAI response to UST at wk3 of induction 100 point CDAI response to UST at wk8 of induction (original response criterion). The overall proportion of remitters & CDAI-100 responders at wk52 of total treatment were calculated for pts with a CDAI-70 response to UST respectively at wk3 or 6 of induction taking into account their relative distribution over the randomized or non-randomised arms receiving 90mg Q8w. Results: Remission rates after 52wks of total treatment in pts receiving 90mg UST Q8w are summarized (see Table). Similarly, CDAI-100 response rates after 52wks of total treatment in pts receiving 90mg UST Q8w were calculated for the different induction response categories. Rates were 60.8%, 58.3% & 59.4% for CDAI-70 responders at wk3, 6, & CDAI-100 responders at wk8 respectively. Conclusions: The majority of pts with CDAI-70 response at either wk3 or 6 after induction also had a CDAI-100 response at wk8. Using different qualifiers for response to UST induction did not result in different response or remission rates after 1 year of treatment in pts treated with UST 90mg Q8w. Funding Agencies: Janssen Research & Development, LLC