Switching from intravenous to subcutaneous infliximab in patients with active inflammatory bowel disease: post-hoc analysis of pre/post switch outcomes from a multicentre, randomised controlled pivotal

ABSTRACT

Introduction: A subcutaneous (SC) infliximab (IFX), CT-P13 SC, has received regulatory approval from the European Medicines Agency for indications including inflammatory bowel disease.1 In response to the coronavirus disease 2019 (COVID-19) pandemic, clinical guidance has recommended considering switching from intravenous (IV) treatment to SC alternatives to minimise hospital visits.2 Aims & Methods: In this analysis, data from the pivotal randomised controlled trial (NCT02883452) of CT-P13 SC in patients with active Crohn's disease (CD) and ulcerative colitis (UC) were analysed to investigate the clinical impact of switching from IV to SC IFX.3 Patients in the CT-P13 IV arm of the pivotal trial received CT-P13 5 mg/kg IV every 8 weeks from Week (W) 6 until W22. At W30, patients switched to receive CT-P13 SC every 2 weeks up to W54 (dose 120 mg or 240 mg for patients <80 kg or ≥80 kg, respectively).3 This post hoc analysis compared per-patient pairwise data at W30 (pre-switch) and W54 (post-switch) from the CT-P13 IV arm for the following outcomes: trough serum concentration (Ctrough;5 μg/mL was considered to be the target exposure level), clinical response (for CD patients, ≥100-point decrease in Crohn's Disease Activity Index score;for UC patients, ≥2-point decrease in partial Mayo score with accompanying ≥1-point decrease in rectal bleeding subscore or an absolute rectal bleeding subscore of 0 or 1) and immunogenicity (anti-drug antibody [ADA] and neutralising antibody [NAb] positivity;as measured by a drug tolerant assay;ADA negative was regarded as NAb negative). For pairwise comparisons, patients with missing data at either W30 or W54 were excluded from the analysis. Statistical comparisons used Fisher's exact test. The differences are reported in a descriptive manner. Results: Overall, 65 patients (25 CD;40 UC) were included in the CT-P13 IV arm. The proportion of patients with a Ctrough level exceeding target exposure was significantly higher post-switch (36/41, 87.8%) than pre-switch (8/41, 19.5%;p<0.00001) (Table). Clinical response rates were comparable at both pre- and post-switch timepoints (40/49 [81.6%] vs 44/49 [89.8%], respectively;p=0.3873). Positive ADA and NAb rates at pre-switch and post-switch were also comparable, in which some changes were regarded from patients with marginal value (Table). Conclusion: Switching from IV to SC IFX did not detrimentally affect the clinical outcomes of patients with active CD or UC. Further, switching from IV to SC IFX might confer more favourable pharmacokinetic outcomes, although larger comparative studies are warranted. (Table Presented).