Ustekinumab Exposure-outcome Analysis in Crohn's Disease Only in Part Explains Limited Endoscopic Remission Rates.

BACKGROUND AND AIMS: Ustekinumab, an anti-IL12/23p40 monoclonal antibody, has been approved for Crohn's disease [CD]. Real-life data in CD patients receiving ustekinumab intravenously [IV] during induction, followed by subcutaneous [SC] maintenance, are lacking. We assessed efficacy of ustekinumab and studied exposure-response correlations. METHODS: We performed a prospective study in 86 CD patients predominantly refractory or intolerant to anti-tumour necrosis factor agents and/or vedolizumab. All received ustekinumab 6 mg/kg IV induction, with 90 mg SC every 8 weeks thereafter. Endoscopic response (50% decrease in Simple Endoscopic Score for CD [SES-CD] at Week 24), endoscopic remission [SES-CD ≤2], and clinical remission [daily stool frequency ≤2.8 and abdominal pain score ≤1] were assessed at weeks 4,8,16, and 24. Further serial analyses included patient-reported outcomes [PRO2], faecal calprotectin [fCal], and ustekinumab serum levels. RESULTS: SES-CD decreased from 11.5 [8.0-18.0] at baseline to 9.0 [6.0-16.0] at week [w]24 [p = 0.0009], but proportions of patients achieving endoscopic response [20.5%] or endoscopic remission [7.1%] were low. Clinical remission rates were 39.5% at w24. After IV induction, fCal dropped from baseline [1242.9 µg/g] to w4 [529.0 µg/g] and w8 [372.2 µg/g], but increased again by w16 [537.4 µg/g] and w24 [749.0 µg/g]. A clear exposure-response relationship was observed, both during induction and during maintenance therapy, with different thresholds depending on the targeted outcome. CONCLUSIONS: In this cohort of refractory CD patients, ustekinumab showed good clinical remission rates but limited endoscopic remission after 24 weeks. Our data suggest that higher doses may be required to achieve better endoscopic outcomes.

Effects of infliximab therapy on transmural lesions as assessed by magnetic resonance enteroclysis in patients with ileal Crohn's disease.

BACKGROUND AND AIMS: Anti TNF therapy induces mucosal healing in patients with Crohn's disease, but the effects on transmural inflammation in the ileum are not well understood. Magnetic resonance-enteroclysis (MRE) offers excellent imaging of transmural and peri-enteric lesions in Crohn's ileitis and we aimed to study its responsiveness to anti TNF therapy. METHODS: In this multi-center prospective trial, anti TNF naïve patients with ileal Crohn's disease and with increased CRP and contrast enhanced wall thickening received infliximab 5 mg/kg at weeks 0, 2 and 6, and q8 weeks maintenance MRE was performed at baseline, 2 weeks and 6 months and assessed based on a predefined MRE score of severity in ileal Crohn's Disease. RESULTS: Twenty patients were included; of those, 18 patients underwent MRE at week 2 and 15 patients at weeks 2 and 26 as scheduled. Inflammatory components of the MRE index decreased by ≥2 points and by ≥50% at week 26 (primary endpoint) in 40% and 32% of patients (per protocol and intention to treat analysis, respectively). The MRE index improved in 44% at week 2 and in 80% at week 26. Complete absence of inflammatory lesions was observed in 0/18 at week 2 and 13% (2/15) at week 26. The obstructive elements did not change. Clinical and CRP improvement occurred as early as wk 2, but only CDAI correlated with the MRE index. CONCLUSION: Improvement of MRE occurs from 2 weeks after infliximab therapy onwards and correlates with clinical response but normalization of MRE is rare.

Fecal calprotectin is a surrogate marker for endoscopic lesions in inflammatory bowel disease.

BACKGROUND: Fecal calprotectin is a marker of inflammation in inflammatory bowel disease (IBD). Since mucosal healing has become a goal of treatment in IBD we examined how reliably calprotectin levels reflect mucosal disease activity. METHODS: In all, 126 IBD patients and 32 irritable bowel syndrome (IBS) patients needing colonoscopy delivered a sample of feces prior to the start of bowel cleansing. Besides collection of symptom scores and blood tests, experienced endoscopists recorded the Simple Endoscopic Score for Crohn's Disease (SES-CD) and the Crohn's Disease Endoscopic Index of Severity (CDEIS) in Crohn's disease (CD) patients and the Mayo endoscopic score in ulcerative colitis (UC) patients. Stool samples were shipped for central calprotectin PhiCal Assay (enzyme-linked immunosorbent assay [ELISA]). Correlation analysis was done with Pearson statistics. RESULTS: The median (interquartile range [IQR]) fecal calprotectin levels were 175 (44-938) µg/g in CD, 465 (61-1128) µg/g in UC, and 54 (16-139) µg/g in IBS. Correlations were significant with endoscopic disease scores in both CD and in UC. Using ROC statistics, a cutoff value of 250 µg/g indicated the presence of large ulcers with a sensitivity of 60.4% and a specificity of 79.5% (positive predictive value [PPV] 78.4%, negative predictive value [NPV] 62.0%) in CD. Levels ≤ 250 µg/g predicted endoscopic remission (CDEIS ≤ 3) with 94.1% sensitivity and 62.2% specificity (PPV 48.5%, NPV 96.6%). In UC, a fecal calprotectin >250 µg/g gave a sensitivity of 71.0% and a specificity of 100.0% (PPV 100.0%, NPV 47.1%) for active mucosal disease activity (Mayo >0). Calprotectin levels significantly correlated with symptom scores in UC (r = 0.561, P < 0.001), but not in CD. CONCLUSIONS: Fecal calprotectin levels correlate significantly with endoscopic disease activity in IBD. The test appears useful in clinical practice for assessment of endoscopic activity and remission.

Therapy of metronidazole with azathioprine to prevent postoperative recurrence of Crohn's disease: a controlled randomized trial.

BACKGROUND & AIMS: More than 80% of Crohn's disease (CD) patients undergoing resection suffer recurrence of their disease. Therapy with aminosalicylates, antimetabolites, or antibiotics leads to a modest reduction in the incidence of recurrence. GOAL: We sought to examine whether metronidazole for 3 months together with azathioprine (AZA) for 12 months is superior to metronidazole alone to reduce recurrence of postoperative CD in "high-risk" patients. METHODS: CD patients undergoing curative ileocecal resection with >or=1 risk factor for recurrence received metronidazole (3 months) and AZA/placebo (12 months). The primary end point was the proportion of patients with significant endoscopic recurrence 3 and 12 months after surgery. Secondary end points included clinical recurrence, safety, and tolerability of treatment. RESULTS: Eighty-one patients were randomized; 19 discontinued the study early. Significant endoscopic recurrence was observed in 14 of 32 (43.7%) patients in the AZA group and in 20 of 29 (69.0%) patients in the placebo group at 12 months postsurgery (P = .048). Intention-to-treat analysis revealed endoscopic recurrence in 22 of 40 (55%) in the AZA group and 32 of 41 (78%) in the placebo group at month 12 (P = .035). At month 12, 7 of 32 patients had no endoscopic lesions in the AZA group, versus 1 of 29 in the placebo group (P = .037). CONCLUSIONS: Despite the enhanced risk of recurrence, the overall incidence of significant recurrence was rather low, probably owing to the metronidazole treatment that all patients received. Concomitant AZA resulted in lower endoscopic recurrence rates and less severe recurrences 12 months postsurgery, predicting a more favorable clinical outcome. This combined treatment seems to be recommendable to all operated CD patients with an enhanced risk for recurrence.

Ornidazole for prophylaxis of postoperative Crohn's disease recurrence: a randomized, double-blind, placebo-controlled trial.

BACKGROUND & AIMS: Crohn's disease almost inevitably recurs after ileocolonic resection, and effective prophylactic therapy has not been identified. We investigated the efficacy and safety of ornidazole, a nitroimidazole antibiotic, for the prevention of clinical recurrence of Crohn's disease after curative ileocolonic resection in a placebo-controlled double-blind clinical trial. METHODS: Eighty patients were randomized to ornidazole 1 g/day or placebo started within 1 week of resection and continued for 1 year. The primary end point was the proportion of patients with clinical recurrence at 1 year. Secondary end points were endoscopic recurrence at 3 months and 12 months after resection. RESULTS: Two patients in the ornidazole group withdrew consent and were not dosed. Ornidazole significantly reduced the clinical recurrence rate at 1 year from 15 of 40 (37.5%) patients in the placebo group to 3 of 38 (7.9%) patients in the ornidazole group (Fisher exact test, 8.03; P = .0046; odds ratio, 0.14; 95% confidence interval, 0.037-0.546). Ornidazole reduced endoscopic recurrence at 12 months from 26 of 33 (79%) in the placebo group to 15 of 28 (53.6%) in the ornidazole group (chi2 , 4.37; P = .037; odds ratio, 0.31; 95% confidence interval, 0.10-0.94). Endoscopic recurrence at 3 and 12 months predicted clinical recurrence. Significantly more patients in the ornidazole group dropped out from the study because of side effects (P = .041). CONCLUSIONS: Ornidazole 1 g/day is effective for the prevention of recurrence of Crohn's disease after ileocolonic resection.

Magnetic resonance imaging of the effects of infliximab on perianal fistulizing Crohn's disease.

OBJECTIVES: Although the clinical efficacy of infliximab as measured by closure of fistulas in Crohn's disease has been demonstrated, its influence on the inflammatory changes in the fistula tracks is less clear. The aim of the present study was to assess the behavior of perianal fistulas before and after infliximab treatment. METHODS: Magnetic resonance imaging (MRI) and clinical evaluation were performed in a total of 18 patients before and after treatment with infliximab. An MRI-based score of perianal Crohn's disease severity was developed using both criteria of local extension of fistulas (complexity, supralavetoric extension, relation to the sphincters and of active inflammation (T2 hyperintensity, presence of cavities/abscesses, and rectal wall involvement). RESULTS: The MRI score was reliable in assessing the fistula tracks, with a good interobserver concordance (p < 0.001). Fistula tracks with signs of active inflammation were found in all 18 patients at baseline and collections in seven. After short-term infliximab treatment, active tracks persisted in eight of 11 patients who had clinically responded to infliximab. After long-term (46 wk) infliximab therapy, MRI signs of active track inflammation had resolved in three of six patients. CONCLUSIONS: We have developed an MRI-based score of perianal Crohn's disease severity to assess the anatomical evolution of Crohn's fistulas. Our study demonstrates that despite closure of draining external orifices after infliximab therapy, fistula tracks persist with varying degrees of residual inflammation, which may cause recurrent fistulas and pelvic abscesses. Whether complete fistula fibrosis occurs over time with repeated infliximab infusions needs further study.

A pilot study on the use of the humanized anti-interleukin-2 receptor antibody daclizumab in active ulcerative colitis.

OBJECTIVES: Medical therapy of refractory ulcerative colitis (UC) is associated with long-term side effects of cyclosporine and steroids. Because cyclosporine acts by inhibiting interleukin-2 (IL-2) production, we studied the efficacy and safety of humanized anti-IL2 receptor (CD25) antibodies daclizumab for refractory UC in an open label pilot study. METHODS: Ten patients with chronically active UC received daclizumab, 1 mg/kg i.v. twice with a 4-wk interval. Clinical, endoscopic, and histological evaluation was scored at regular intervals. CD25 immunohistochemistry was followed in mucosal biopsies. The primary study endpoint was clinical improvement at wk 8. RESULTS: Nine of 10 patients completed the study. The median clinical activity score decreased from a median of 8 (95% CI = 7.2-9.2) at baseline to 3.5 (95% CI = 1.4-4.9) at wk 8 (p < 0.005). Endoscopic scores were significantly decreased at wk 8 (wk 0: 8, 95% CI = 6.3-8.5; wk 8: 5.0, 95% CI = 2.6-6.3; p < 0.01). Mucosal biopsies showed a significant decrease in CD25+ cells, and there was a trend toward lower histology scores at wk 8. Quality of life as assessed by the Inflammatory Bowel Disease Questionnaire increased after therapy (baseline: 131, 95% CI = 119-178; wk 8: 169; 95% CI = 124-216, p < 0.05). Nausea was most frequently reported as an adverse event, but always in patients that were concomitantly started on azathioprine. CONCLUSIONS: The anti-IL-2R antibody daclizumab was safe and well tolerated in acute UC. Patients experienced clinical benefit along with signs of endoscopic improvement, but further controlled trials are needed to determine the therapeutic benefit of this compound.