Subcutaneous Infliximab (CT-P13 SC) as Maintenance Therapy for Inflammatory Bowel Disease: Two Randomized Phase 3 Trials

Background and Aims CT-P13 subcutaneous (SC), an SC formulation of the intravenous (IV) infliximab biosimilar CT-P13 IV, creates a unique exposure profile. We aimed to demonstrate superiority of CT-P13 SC versus placebo as maintenance therapy in patients with Crohn’s disease (CD) and ulcerative colitis (UC). Methods Two randomized, placebo-controlled, double-blind studies were conducted in patients with moderately-to-severely active CD or UC and inadequate response/intolerance to corticosteroids and immunomodulators. All patients received open-label CT-P13 IV 5 mg/kg at weeks (W) 0, 2, and 6. At W10, clinical responders were randomized (2:1) to CT-P13 SC 120 mg or placebo every 2 weeks until W54 (maintenance phase) using pre-filled syringes. (Co-)primary endpoints were clinical remission and endoscopic response (CD) and clinical remission (UC) at W54 (all-randomized population). Results Overall, 396 patients with CD and 548 patients with UC received induction treatment. At W54 in the CD study, statistically significant higher proportions of CT-P13 SC- versus placebo-treated patients achieved clinical remission (62.3% versus 32.1%; P < 0.0001) and endoscopic response (51.1% versus 17.9%; P < 0.0001). In the UC study, clinical remission rates at W54 were statistically significantly higher with CT-P13 SC versus placebo (43.2% versus 20.8%; P < 0.0001). Achievement of key secondary endpoints was significantly higher with CT-P13 SC versus placebo across both studies. CT-P13 SC was well tolerated, with no new safety signals identified. Conclusion CT-P13 SC was more effective than placebo as maintenance therapy and well tolerated in patients with moderately-to-severely active CD or UC who responded to CT-P13 IV induction. ClinicalTrials.gov, NCT03945019 (CD) and NCT04205643 (UC).