P661 Clinical response over 24 weeks for initial and delayed responders to induction therapy with risankizumab in Crohn’s disease: data from the ADVANCE and MOTIVATE studies

Background The efficacy and safety of risankizumab (RZB) in patients with Crohn’s disease (CD) has been demonstrated.1,2 We reported that an additional 12 weeks (ie, induction period 2) of RZB therapy could induce clinical response in patients with CD who did not achieve clinical response after an initial 12-week induction period.3 In this post hoc analysis, we report the proportion of patients who achieved clinical response over 24 weeks (initial and delayed responders to RZB induction therapy). Methods Data were pooled from the ADVANCE and MOTIVATE phase 3 RZB studies. Patients who had not achieved stool frequency (SF)/abdominal pain score (APS) clinical response (≥ 30% decrease in average daily SF and/or ≥ 30% decrease in average daily APS and both not worse than baseline) after an initial 12-week induction with intravenous (IV) RZB (600 mg or 1200 mg) at weeks 0, 4, and 8 were rerandomized 1:1:1 in induction period 2 to receive IV RZB 1200 mg (at weeks 12, 16, and 20) or subcutaneous (SC) RZB (180 mg or 360 mg at weeks 12 and 20) in a double-dummy–blinded fashion. In this post hoc analysis, efficacy was analysed in patients treated with either 600 mg RZB IV or placebo (PBO) for 12 weeks in the PBO-controlled induction period and patients who did not achieve clinical response with 600 mg RZB IV for 12 weeks and were rerandomized to 360 mg RZB SC every 8 weeks during induction period 2 (currently marketed RZB doses). SF/APS clinical response was assessed at week 12 for initial responders and at week 24 for delayed responders in induction period 2. Non-responder imputation with no special data handling for data missing due to COVID-19 was used. No multiplicity adjustment was performed. Results Of the 889 patients randomised to 600 mg IV RZB or PBO in the induction studies, 70.0% (369/527) in the RZB group compared with 45.6% (165/362) in the PBO group achieved SF/APS clinical response at week 12. Of the 47 patients who did not achieve initial clinical response to 600 mg IV RZB and received 360 mg SC in induction period 2, 32 (68.1%) achieved delayed SF/APS clinical response at week 24. The proportion of patients achieving SF/APS clinical response over 24 weeks (either initial or delayed responders) was 89.1% (401/450). The safety profile of RZB in patients with CD has been reported.1,2 Conclusion In patients with moderate-to-severe CD, RZB treatment leads to approximately 9 of 10 patients achieving either initial (600 mg IV) or delayed (600 mg IV followed by 360 mg SC) clinical response over 24 weeks. References: 1. D’Haens G, et al. Lancet. 2022; 399: 2015-30. 2. Ferrante M, Panaccione R, et al. Lancet. 2022; 399: 2031-46. 3. D’Haens G, et al. United European Gastroenterol J. 2021; 9(S8): 96-7.