P1008 Subcutaneous infliximab in IBD patients previously treated with an optimized intravenous infliximab dosing schedule: preliminary results on expectations and satisfaction of switching from intravenous to subcutaneous infliximab
Authors: Moens A , Holvoet T , Bossuyt P , Lobaton T , Posen A , Cremer A , Capirchio L , Caenepeel C , Lambrecht G , Amezaga A J , Reenaers C , Peeters H , Willandt B , Deprez N , De Rechter J , Arijs I , Straetemans N , Dreesen E , Ferrante M ,   Belgian IBD Research and Development (BIRD)
Published: January 2025

Abstract

Background
The anti-TNF agent infliximab (IFX) CT-P13 is now available as a subcutaneous (SC) formulation. Unanswered questions persist regarding the use of SC IFX in patients previously on optimized intravenous (IV) regimens. The AMARETTO study investigates if switching to weekly SC IFX 120 mg is associated with better outcomes than bi-weekly dosing in patients with prior optimized IV therapy.

Methods
This multicentre, randomized, open-label superiority trial includes adult IBD patients treated with optimized IV IFX in steroid-free clinical (PRO-2) and biological remission (CRP &lt;10 mg/L, and faecal calprotectin &lt;250 μg/g) on optimized IV IFX (ClinicalTrials.gov ID: NCT06113913). Eligible patients may continue their IV treatment (IV comparison group) or switch to SC IFX. Those switching to SC are randomized 1:1 to open-label weekly (SC intervention) or bi-weekly 120 mg SC IFX (SC comparison). Primary endpoint is the proportion maintaining steroid-free clinical and biological remission at week 52 without treatment optimization. Here we focus on the secondary endpoints of patient expectations, experience and satisfaction using a 11-point Likert scale (0 = lowest and 10 = highest).

Results
From May to October 2024, 163 patients were screened, with 120 included (66 SC, 54 IV; Table 1). Among the 66 SC patients willing to switch, 57 (37 CD, 20 UC/IBDU) already had their baseline visit with first SC IFX and completed the treatment expectations questionnaire, and 29 have already been treated with SC IFX for at least 8 weeks and completed a satisfaction questionnaire (Figure 1). The pen was preferred by 42 (74%), the syringe by 4 (7%), and 11 patients (19%) had no preference. Key reasons for pen preference were needle visibility (38%) and injection control (48%). Training for SC injection was mainly provided by IBD nurses (N=45, 79%). Median (interquartile range, IQR) satisfaction with training, confidence, and ease of use were 10 (9–10), 9 (8–10), and 9 (8–10), respectively. By week 8, median (IQR) scores for confidence remained stable at 9 (9–10) and increased for ease of use 10 (8–10). Median (IQR) scores for injection pain and fear at week 8 were 2 (0–4) and 0 (0–1). Satisfaction and likelihood of recommending SC treatment were both 9 (8–10). No significant differences at week 8 were observed between both SC groups.

Conclusion
Preliminary data suggest a highly positive patient experience with SC IFX among those previously treated with optimized IV IFX, highlighting strong preferences for the pen and good satisfaction rates regarding training, ease of use, confidence and injection pain. The AMARETTO trial will further clarify if weekly SC dosing offers superior outcomes compared to bi-weekly SC IFX.