P1074 Impact of body mass index (BMI) on clinical outcomes and drug levels in patients with Crohn’s disease receiving maintenance treatment with subcutaneous infliximab: A post hoc analysis of the LIBERTY-CD study

Abstract

Abstract Background Obesity and high levels of visceral adipose tissue are associated with lower response rates to intravenous (IV) infliximab (IFX).1 Subcutaneous (SC) IFX is a novel formulation that demonstrated superiority to placebo as maintenance therapy in patients (pts) with moderate-to-severe active Crohn’s disease (CD) in the Phase 3 LIBERTY-CD study. Assessing efficacy of SC IFX by BMI is important as, unlike the IV formulation, pts receive a fixed dose. This post hoc analysis aimed to assess the association between BMI and the efficacy of SC IFX therapy. Methods Data from LIBERTY-CD (NCT03945019) were analysed; 231 pts from the SC IFX arm were divided into four subsets by their BMI: underweight (BMI <18.5 kg/m2, n=27); normal (18.5–24.9 kg/m2, n=133); overweight (25–29.9 kg/m2, n=53); obese (≥30 kg/m2, n=18). Co-primary endpoints at Week (W) 54 (clinical remission [CD Activity Index (CDAI) score <150]; endoscopic response [≥50% decrease in Simple Endoscopic Score for CD (SES-CD) from baseline (BL)]) and W54 change from BL in CDAI score were assessed by BMI subset. Correlations between BMI and CDAI score, SES-CD or median trough level of infliximab (TLI), and the impact of BMI on W54 TLI, were evaluated. Analyses were conducted in a descriptive manner. Results At W54, there were no statistically significant differences in co-primary endpoints or change from BL in CDAI score across BMI subsets, despite descending trends in rates of achieving co-primary endpoints, change in CDAI score and TLI with increasing BMI (Table). From the underweight to obese subsets, clinical remission rates were 63.0%, 66.2%, 58.5% and 44.4% (p=0.125), endoscopic response rates were 55.6%, 36.1%, 41.5% and 27.8% (p=0.207) and median changes from BL in CDAI score were −227.3, −212.9, −196.2 and −204.5 (p=0.358). No significant correlations were observed between BMI and CDAI score (Pearson r=0.0972/p=0.141; Spearman rank r=0.0619/p=0.349) or BMI and SES-CD (Pearson r=0.0446/p=0.507; Spearman rank r=0.0375/p=0.577), while there was a weak, but significant, negative correlation between BMI and TLI (Pearson r=−0.2808/p<0.001; Spearman rank r=−0.2829/p<0.001) (Figure). Additionally, there was a significant difference in median W54 TLI across BMI subsets from underweight to obese (17.0, 13.6, 9.3 and 6.6 µg/mL; p=0.007) (Table). Conclusion While there was a significant difference in TLI across BMI subsets, there was no statistically significant impact of BMI on W54 clinical or endoscopic outcomes. These results could be explained by the relatively high TLI achieved with the SC formulation. Further larger and longer-term studies including pts with morbid obesity and utilising body composition assessment are warranted. 1Yarur A et al. Gastroenterology 2023;165:963–75.