Ha, Christina

Objective Perianal Crohn’s disease (pCD) occurs in up to 40% of patients with CD and is associated with poor quality of life, limited treatment responses and poorly understood aetiology. We performed a genetic association study comparing CD subjects with and without perianal disease and subsequently performed functional follow-up studies for a pCD associated SNP in Complement Factor B ( CFB ). Design Immunochip-based meta-analysis on 4056 pCD and 11 088 patients with CD from three independent cohorts was performed. Serological and clinical variables were analysed by regression analyses. Risk allele of rs4151651 was introduced into human CFB plasmid by site-directed mutagenesis. Binding of recombinant G252 or S252 CFB to C3b and its cleavage was determined in cell-free assays. Macrophage phagocytosis in presence of recombinant CFB or serum from CFB risk, or protective CD or healthy subjects was assessed by flow cytometry. Results Perianal complications were associated with colonic involvement, OmpC and ASCA serology, and serology quartile sum score. We identified a genetic association for pCD (rs4151651), a non-synonymous SNP (G252S) in CFB , in all three cohorts. Recombinant S252 CFB had reduced binding to C3b, its cleavage was impaired, and complement-driven phagocytosis and cytokine secretion were reduced compared with G252 CFB. Serine 252 generates a de novo glycosylation site in CFB. Serum from homozygous risk patients displayed significantly decreased macrophage phagocytosis compared with non-risk serum. Conclusion pCD-associated rs4151651 in CFB is a loss-of-function mutation that impairs its cleavage, activation of alternative complement pathway, and pathogen phagocytosis thus implicating the alternative complement pathway and CFB in pCD aetiology.

Abstract Background Improvement in clinical outcomes and normalisation of objective markers of inflammation, high-sensitivity C-reactive protein (hs-CRP) and faecal calprotectin (FCP), are considered treatment targets per STRIDE-II guidelines.1 We evaluated the effect of the oral selective Janus kinase inhibitor upadacitinib (UPA) on changes in hs-CRP, FCP, and clinical outcomes in patients with Crohn’s disease (CD). Methods In 2 phase 3, randomized, double-blind, placebo-controlled induction studies (U-EXCEL, NCT03345849; U-EXCEED, NCT03345836), patients with moderate-to-severe CD received 12-week treatment with UPA 45 mg (UPA45) once daily (QD) or placebo (PBO). Patients with clinical response to UPA45 were rerandomised in U-ENDURE (NCT03345823) to receive 52-week maintenance treatment with UPA 30 mg QD (UPA30), UPA 15 mg QD (UPA15), or PBO. Endpoints included marker normalisation (hs-CRP ≤ 5 mg/L, FCP ≤ 250 µg/g) in patients with elevated baseline marker levels, normal marker and clinical remission by Crohn’s Disease Activity Index (CDAI < 150) or very soft/liquid stool frequency (SF)/abdominal pain score (APS) (average daily SF ≤ 2.8 and average daily APS ≤ 1, neither greater than baseline), and ≥ 50% reduction from baseline in marker values with a decrease of at least 100 points in CDAI from baseline. Median changes from baseline in marker levels were also evaluated. Non-responder imputation with no special data handling for missing data due to COVID-19 was used. Results Of 1021 enrolled patients, 645 (63.2%) had elevated hs-CRP (> 5 mg/L) and 750 (73.5%) had elevated FCP (> 250 µg/g) levels at baseline. Significantly greater proportions of patients with elevated baseline marker levels achieved normalisation with UPA compared with PBO at week 12 (Fig 1A/B) and week 52 (Fig 2A/B; nominal P < .001 for all). Decreases in marker levels from baseline with UPA were observed as early as week 2 and were significantly greater than with PBO through week 12 (Fig 1C) and week 52 (Fig 2C; nominal P < .001 for all). Patients achieved clinical endpoints and improvements in markers at significantly higher rates with UPA45 vs PBO at week 12 (Fig 1D–F) and with UPA15 and UPA30 vs PBO at week 52 (Fig 2D–F; P < .001 for all). The safety profile of UPA in CD was previously reported and no new safety concerns were identified. Conclusion Improvements in clinical endpoints and normalisation of objective markers of inflammation were achieved as early as week 2 with UPA45 induction and sustained with UPA15 and UPA30 maintenance therapy in patients with CD. Median changes in hs-CRP and FCP with UPA support continued improvement of inflammation up to week 52. 1. Turner D., et al. Gastroenterology. 2021;160(5):1570–1583.

Abstract Background Tofacitinib is an oral, small molecule Janus kinase inhibitor for the treatment of ulcerative colitis (UC). Efficacy and safety of tofacitinib were demonstrated in the OCTAVE clinical programme.1,2 Here, we present an analysis of the number and causes of UC-related hospitalisations during the OCTAVE clinical programme. Methods This descriptive analysis comprised patients (pts) hospitalised for UC who received placebo or tofacitinib 10 mg twice daily (BID) in OCTAVE Induction 1&2 (NCT01465763; NCT01458951)1, and pts who received placebo, or tofacitinib 5 or 10 mg BID in OCTAVE Sustain (NCT01458574)1, or ≥1 dose of tofacitinib in OCTAVE Open (NCT01470612)2; it includes data from pts with ≤7.8 years of tofacitinib exposure. We examined the demographic and clinical characteristics, proportions, causes and other aspects of UC-related hospitalisations in pts treated with placebo or tofacitinib in the OCTAVE clinical programme. Results Overall, 1139 pts with UC were included in this analysis. Demographic and disease characteristics of pts with UC-related hospitalisations were generally similar across treatment groups in each study; most pts were <40 years old, had pancolitis, a mean total Mayo score >8, prior treatment with oral corticosteroids and immunosuppressants (Table 1). Ninety-five pts had UC-related hospitalisations; of whom 92 had one UC-related hospitalisation and 3 pts were hospitalised twice (Table 2). In OCTAVE Induction 1&2, OCTAVE Sustain and OCTAVE Open, 2.1%, 1.0% and 6.6% of pts, respectively, had UC-related hospitalisations with tofacitinib 10 mg BID vs 1.0% and 2.9% of pts receiving tofacitinib 5 mg BID in OCTAVE Sustain and OCTAVE Open, and 3.4% and 4.0% of pts receiving placebo in OCTAVE Induction 1&2 and OCTAVE Sustain, respectively. UC-related hospitalisations did not lead to temporary treatment discontinuations in most pts (Table 2). The most frequent cause of UC-related hospitalisations in tofacitinib- and placebo-treated pts was non-surgical UC-related events (ie, UC flares; Table 2). Conclusion UC-related hospitalisations were infrequent in the OCTAVE clinical programme, and rates were generally lower than those reported in a real-world assessment of pts with UC treated with biological therapies.3 Most hospitalised pts were aged <40 years with severe disease and prior corticosteroid and immunosuppressant exposure. The most common cause of hospitalisation was non-surgical UC-related events. References: 1. Sandborn WJ et al. N Engl J Med 2017;376:1723-1736. 2. Sandborn WJ et al. Aliment Pharmacol Ther 2022;55:464-478. 3. Bressler B et al. J Crohn’s Colitis 2021;15:1694-1706.

Abstract Background Small bowel fibrostenotic strictures are common in patients with Crohn’s disease (CD). No global consensus recommendations on definitions, diagnosis and clinical management are available. Methods Several systematic reviews followed by a RAND/University of California Los Angeles appropriateness study on the definitions, diagnosis and clinical management of fibrostenosing CD in clinical practice were performed. A panel of 28 global experts and a patient representative were convened. They assessed a total of 152 candidate items. The items were subsequently evaluated for appropriateness. Results No accurate predictive biomarkers are available for naïve or anastomotic fibrostenosing strictures. Accurate diagnosis of fibrostenosing CD requires cross-sectional imaging which should evaluate bowel wall thickness, luminal narrowing and prestenotic dilatation. A potential inflammatory component should be assessed. Abdominal cross-sectional imaging was considered necessary prior to any treatment decision. The panel proposed an approach to medical, endoscopic, and surgical therapies (Figure 1 and Table 1). Technical characteristics for endoscopic balloon dilation and follow up strategies after successful dilation therapy were identified. Appropriateness, types and performance of different surgical approaches in various settings were evaluated. Conclusion This global consensus provides clinical guidance for the diagnostic and therapeutic management of patients with fibrostenotic CD.