Introduction

Management of perianal fistulas in Crohn’s disease (CD) is challenging and requires a multidisciplinary approach, combining surgical drainage and biologic therapies, such as infliximab (IFX). Higher IFX trough concentrations have been associated with improved fistula healing rates. The subcutaneous (SC) formulation of IFX achieves 2–3 times higher and more stable trough levels compared to intravenous (IV) formulation. This study hypothesizes that SC IFX could enhance perianal fistula healing rates in CD patients.

Aims & Methods

REMSILAP study is part of the 3TLAP cohort, a French prospective multicenter observational study evaluating optimal therapeutic strategies for achieving clinical and radiological remission of perianal fistulas in CD at 12 months post-surgical drainage. The REMSILAP substudy focuses specifically on patients receiving SC IFX. Patients who received SC IFX after or within six months prior to surgical drainage were included. Baseline was defined as the day of surgical drainage. The primary outcome was the proportion of patients achieving complete clinical remission defined as Perianal Disease Activity Index (PDAI) fistula drainage subscore = 0 associated with PDAI activity restriction subscore <3 and absence of seton, and radiological remission at 12 months. Here, we present preliminary findings from REMSILAP.

Results

Among the 353 patients enrolled in the 3TLAP cohort, 54 were included in REMSILAP. The cohort consisted of 61.1% male patients, with a median age of 36 years and a median disease duration of 4.5 years. Penetrating disease (B3 phenotype) was present in 40.7%, and 33.3% had a history of surgical resection. At baseline, 40.7% of patients had quiescent disease regarding Harvey-Bradshaw index, while 5.6% had severe disease activity. Biologic exposure prior to inclusion was noted in 42.6%. Surgical drainage, with seton placement, was performed in 74.1% of patients. Forty-eight patients (88%) initiated SC IFX treatment after surgical drainage. Of the patients receiving SC IFX, 50% transitioned to SC IFX after less than three IV infusions. Among those on IV IFX at baseline, 20.4% were receiving a 10 mg/kg dose. Forty-three patients (79.6%) received SC IFX in combination with immunomodulators (azathioprine, methotrexate, or 6-mercaptopurine). The median duration of SC IFX treatment was 13.1 months, with treatment maintained for 67.5% of the follow-up period (mean: 19.3 ± 11.3 months). Forty-three patients (79.6%) were treated with a stable dose of 120 mg/14 days and 6 patients (11.1%) had an intensification of SC IFX dosage to 120mg / 7 days. At 12 months, 42 patients were evaluable for clinical outcomes. Complete clinical healing at 12 months was achieved in 11 patients (27.5%) and association of PDAI restriction subscore <3 and drainage subscore = 0 was found in 18 patients (42.9%). Thirteen patients (34.2%) from the 25 patients who had received at least 6 months of SC IFX treatment showed clinical healing at 6 months. Out of the 26 patients treated with at least 12 months of SC IFX treatment, clinical healing was achieved in 16 patients (61.5%) at 12 months. Among the 11 patients with clinical healing at 12 months, 8 (72.2%) were treated with SC IFX treatment following more than three IFX IV infusions. None of the 11 patients with available MRI date showed radiological healing at 12 months.

Conclusion

Subcutaneous infliximab following surgical drainage of Crohn’s disease perianal fistula demonstrates high treatment persistence and promising rates of fistula healing.

Disclosure

This study was funded by Celltrion Healthcare France

Introduction

Although endoscopic balloon dilation (EBD) remains the standard intervention for Crohn’s disease (CD)-associated strictures, its efficacy is limited by high recurrence and surgery rates. Retrospective analyses suggest endoscopic stricturotomy (ES) may offer superior outcomes, particularly in anastomotic strictures. However, no randomized trials have directly compared EBD and ES for short CD-related strictures.

Aims & Methods

This single-center, randomized controlled trial (August 2022–March 2025) enrolled adult CD patients (18–65 years) with symptomatic, predominantly fibrotic or mixed, short strictures (<3 cm), including both de novo and anastomotic types, accessible via standard endoscopy. Patients with multiple (>2) strictures, strictures beyond endoscopic reach, or prior stricturotomy were excluded. Participants were randomized to undergo either EBD or ES. The primary outcome was clinical recurrence at 1 year. Secondary outcomes included re-intervention, surgery, emergency visits, hospitalization, technical success, and adverse events.

Results

Out of 70 randomized patients, 69 were analyzed (EBD: 35; ES: 34). Baseline characteristics were comparable between groups. Technical success was similar (EBD: 91.4%, ES: 94.1%). On time to event analysis, clinical recurrence was significantly lower in the ES group (OR=0.343, 95% CI: 0.134–0.881; p=0.026). Re-intervention rates favored ES (EBD: 25.7%, ES: 8.8%; OR=0.337, 95% CI: 0.131–0.870; p=0.025). Surgery rates were numerically lower with ES (EBD: 11.4%, ES: 5.9%) but not statistically significant (p=0.581). Hospitalization was significantly more frequent in the EBD arm (OR=0.276, 95% CI: 0.091–0.840; p=0.023). ED visits also trended lower with ES, though not statistically significant (p=0.062) (see table). Adverse events occurred in 25.7% of EBD patients (bleeding n=3 [1 hemoclip], pain with admission n=3, micro-perforation n=1, post-procedure pain n=2) and 14.7% of ES patients (bleeding n=3 [1 self-limited, 1 coagrasper, 1 hemoclip], none required transfusion, suspected perforation n=1, mild pain n=1).

Conclusion

In this interim analysis, ES was associated with significantly lower clinical recurrence, re-intervention, and hospitalization compared to EBD for short CD-related strictures, with similar safety outcomes. These findings support ES as a potentially superior first-line endoscopic strategy over EBD in selected patients with Crohn’s disease strictures. (NCT05521867)

References

Lan N, Shen B. Endoscopic Stricturotomy Versus Balloon Dilation in the Treatment of Anastomotic Strictures in Crohn's Disease. Inflamm Bowel Dis. 2018 Mar 19;24(4):897-907. doi: 10.1093/ibd/izx085. PMID: 29546384.

Introduction

A dysfunctional intestinal mucosal barrier is a key pathophysiological hallmark and driver of a broad range of gastrointestinal diseases including celiac disease and inflammatory bowel disease. To date, there are no adequate treatment strategies to ameliorate impaired barrier function.
IMU-856 is an orally available and systemically acting small molecule modulator of sirtuin 6 (SIRT6), a histone/non-histone protein deacetylase which serves as a transcriptional regulator of intestinal barrier function and regeneration of bowel epithelium. IMU-856 may represent a new approach to treat gastrointestinal diseases with compromised barrier function.

Aims & Methods

This was a first-in-human, double-blind, randomized, placebo-controlled clinical trial of IMU-856 in healthy volunteers and patients with celiac disease. In the multiple ascending dose part, healthy human subjects were dosed once-daily for 14 consecutive days with IMU-856 at three different dose levels or placebo. Additionally, the Phase 1/1b study was designed to assess safety and tolerability of IMU-856 at two different dose levels in patients with celiac disease during periods of gluten-free diet and a 15-day gluten challenge. Further objectives included pharmacokinetics and the assessment of histological changes. Biomarkers reflecting intestinal enterocyte mass and function, nutrient absorption, and enteroendocrine hormones like GLP-1 were analyzed to assess potential effects on gut health.

Results

IMU-856 was safe and well-tolerated with a benign adverse event profile and pharmacokinetics that allow once-daily dosing. Treatment with IMU-856 protected against gluten-induced histologic deterioration, improved the health and metabolic function of intestinal enterocytes as measured by nutrient uptake and citrulline [1], and had positive effects on enteroendocrine cells increasing endogenous GLP-1 levels in a dose-dependent manner.

Conclusion

IMU-856 is a safe, highly selective and potent epigenetic modulator, improving the intestinal barrier function in patients with celiac disease undergoing a gluten challenge.
Positive effects of IMU-856 on gut hormones and various biomarkers for overall gut health including intestinal function and integrity were observed. Therefore, IMU-856 may offer extensive potential for treatment of gastrointestinal diseases with compromised intestinal barrier function and metabolic diseases.

References

1. Daveson AJM, Stubbs R, Polasek TM, Isola J, Anderson R, Tye-Din JA, et al. Safety, clinical activity, pharmacodynamics, and pharmacokinetics of IMU-856, a SIRT6 modulator, in coeliac disease: a first-in-human, randomised, double-blind, placebo-controlled, phase 1 trial.

Disclosure

AS, MW, EP: employees of Immunic AG, option and shareholders of Immunic, Inc.
IPO, JF, IK, SE: employees of Immunic AG, option and/or shareholders of Immunic, Inc.
HK: employee of Immunic AG, shareholder of Immunic, Inc., co-inventor of patents for the drug in investigation
DP: option holder of Immunic, Inc.
DV, AM: employees of Immunic AG and Immunic, Inc., shareholders of Immunic, Inc., co-inventors of patents for the drug in investigation