Comparative Efficacy of Biologic Therapies for Inducing Response and Remission in Fistulizing Crohn's Disease: Systematic Review and Network Meta-Analysis of Randomized Controlled Trials.

BACKGROUND: The medical treatment of fistulizing Crohn's disease (CD) remains a challenge to clinicians. Over the last 20 years, biologic therapies have been the mainstay of medical treatment of fistulizing CD. The purpose of this study is to compare the efficacy of biologic therapies in inducing response and remission in fistulizing CD. METHODS: We performed a systematic review of the EMBASE, MEDLINE, and Cochrane Central databases from inception to December 2021. Inclusion criteria were any randomized controlled trials (RCTs) that evaluated the efficacy of biologic therapies against an active comparator or placebo for induction of response or remission in adults with fistulizing CD. The proportion of patients with fistula response or remission, as defined by each clinical trial, was our primary study outcome. A Bayesian random-effects network meta-analysis was used to measure treatment effects and results were reported as odds ratio (OR) and 95% confidence interval (CI). RESULTS: In our analysis, 10 studies were included, and all were RCTs. Infliximab was superior to adalimumab in inducing response (OR, 0.24; 95% CI, 0.06-0.99) but not in inducing remission (OR, 0.31; 95% CI, 0.04-2.27). Tumor necrosis factor antagonists were superior to placebo in the induction of response (OR, 0.51; 95% CI, 0.35-0.750) and remission (OR, 0.36; 95% CI, 0.22-0.58). Infliximab was superior to placebo in inducing response (OR, 0.36; 95% CI, 0.17-0.75) and remission (OR, 0.17; 95% CI, 0.03-0.87). Ustekinumab was superior to placebo in inducing response (OR, 0.48; 95% CI, 0.26-0.860) but not in inducing remission (OR, 0.50; 95% CI, 0.13-1.93). When comparing biologic therapies against each other, there was no statistical difference in inducing remission. Vedolizumab was not superior to placebo in inducing remission (OR, 0.32; 95% CI, 0.04-2.29). Certolizumab was not superior to placebo in inducing response (OR, 0.78; 95% CI, 0.40-1.55) or remission (OR, 0.78; 95% CI, 0.40-1.55). CONCLUSIONS: Tumor necrosis factor antagonists are effective in inducing response and remission in fistulizing CD. Infliximab was superior to adalimumab for inducing response but not for inducing remission. Ustekinumab is effective in the induction of response but not in the induction of remission. When compared against each other, biologic therapies showed no significant difference in the induction of remission. Based on the available data, infliximab is the preferred first-line treatment. As for other biologics, the limited published data do not allow us to make firm recommendations. This study supports current practice and emphasizes the need for dedicated RCTs to evaluate the efficacy of biologic therapies in fistulizing CD.

Despite the era of biologic therapies, the management of fistulizing Crohn's disease remains challenging. This is the first systematic review and network meta-analysis to compare the efficacy of biologic therapies in inducing response and remission in patients with fistulizing Crohn's disease. We found that anti-tumor necrosis factor agents are effective in inducing response and remission. Infliximab was superior to adalimumab for inducing response but not for inducing remission.

Efficacy of Intravenous Ustekinumab Reinduction in Patients With Crohn's Disease With a Loss of Response.

Background/Aims: In patients receiving ustekinumab (UST) for treatment of Crohn's disease, there is no proven strategy to enhance or re-capture response. We assessed the utility of UST intravenous (IV) reinduction (~6 mg/kg) to achieve clinical, biochemical and endoscopic response or remission, in patients with partial or loss of response to UST maintenance therapy. Methods: A multicentre, retrospective cohort study was performed. Adults who received an IV reinduction dose of UST for either partial response or secondary loss of response to UST were assessed. The primary outcome was clinical remission off corticosteroids (Harvey Bradshaw Index <5), with biochemical response (defined as ≥ 50% decrease of CRP or FCP and/or endoscopic response (defined as a decrease in Simple Endoscopic Score-CD ≥ 50%). Secondary outcomes included clinical, biomarker and endoscopic response/remission, as well as safety. Results: Sixty-five patients (median age 38 years, 54.7% women) underwent IV UST reinduction between January 2017 and April 2019. Most patients (88.3%) were already on escalated maintenance dosing of UST 90 mg subcutaneous every 4 weeks. Clinical outcomes were assessed at a median of 14 weeks (IQR: 12-19) post-reinduction. The primary outcome of clinical remission off corticosteroids with biochemical and/or endoscopic response was achieved in 31.0% (n = 18). Pre-reinduction UST concentrations were ≥1 µg/mL in 88.6% (mean 3.2 ± 2.0 µg/mL). No serious adverse events were reported. Conclusions: UST IV reinduction can be effective in patients with Crohn's disease with partial or loss of response to UST maintenance therapy. Further studies evaluating this strategy are warranted.

Comparison of Serum Concentrations of Ustekinumab Obtained by Three Commercial Assays in Patients with Crohn's Disease.

BACKGROUND: Data on the association of ustekinumab (UST) drug concentrations and clinical outcomes are conflicting. We assessed serum UST drug and anti-UST antibody concentrations using three commercially available assays. METHODS: Sixty-one blood samples were analyzed for serum UST drug and anti-UST antibody concentrations using three assays: one homogeneous mobility shift assay (HMSA, Prometheus, Assay A), and two enzyme-linked immunosorbent assays (ELISA; Progenika, Dynacare, Assay B and Theradiag, Assay C). RESULTS: The median (IQR) serum UST concentrations for the three assays were: Assay A 7.50 (5.35 to 12.88) µg/mL, Assay B 4.02 (2.46 to 6.95) µg/mL and Assay C 4.35 (2.62 to 7.50) µg/mL. A Kruskal-Wallis test confirmed a statistically significant difference between the different assays, X2(2) = 30.606, p < 0.001. Linear regression showed near twofold increased difference in the absolute drug concentrations between the HMSA and either ELISA. Linear quantitative correlation was observed for all three assays (r = 0.836 for A versus B, r = 0.792 for A versus C, r = 0.936 for B versus C; p < 0.01). The intraclass correlation coefficient (ICC) between assay A and B was 0.649 (95% confidence interval [CI] -0.208 to 0.874); assay A and C was 0.671 (95% CI -0.165 to 0.878); and assay B and C was 0.958 (95% CI 0.928 to 0.975); p < 0.001. No anti-UST antibodies were detected. CONCLUSION: A good correlation was observed for serum UST drug concentrations and a good agreement was observed between the ELISA tests. However, agreement was poor between the HMSA and each ELISA tests. Clinical recommendations regarding drug concentrations should be based on assay type used.

Certolizumab Trough Levels and Antibodies in Crohn Disease: A Single-Center Experience.

Background: Certolizumab pegol (CZP) has been successfully used for the treatment of Crohn disease (CD); however, real-world data regarding the utility of CZP trough levels (CTLs) are lacking. We aimed to correlate CTL with CD outcomes and to determine frequency of CZP antibodies. Methods: Retrospective evaluation of all CD patients on maintenance CZP with CTL obtained between 2016 and 2019. Outcomes included: median CTL, presence of anti-CZP antibodies, biochemical response (BR), clinical response (CR), radiologic response (RR), radiologic healing (RH), and mucosal healing (MH). Results: Seventy-seven CD patients were included. Median CTL was 18.9 µg/mL (interquartile range, 7.6-35.4). Twenty-three patients (27.3%) had positive antibody levels, with lower median CTL compared to patients with no antibodies (0.0 vs 29.8; P < 0.0001). Median CTL levels were higher in patients with vs without CR (30.4 vs 10.3 µg/mL; P = 0.0015) and RR (29.6 vs 5.8 µg/mL; P = 0.006). CZP dosing at least every 2 weeks was associated with higher odds of achieving MH (odds ratio, 3.2; 95% confidence interval, 1.03-9.97). CTL resulted in change in clinical management in 62.7% of cases and presence of CMZ antibodies was associated with an odds ratio of 5.83 (95% confidence interval, 1.57-21.73) of change in management. Receiver operating characteristic curve and quartile analysis suggested that CTL >19 µg/mL is associated with increased rates of CR and RR. Conclusions: Higher CTL was significantly associated with CR and RR. The rate of CZP antibodies was 27.3%. Our data suggest maintenance CTL of ≥19 µg/mL should be achieved in order to optimize outcomes in clinical practice.

Combination Biologic Therapy in Inflammatory Bowel Disease: Experience From a Tertiary Care Center.

The global incidence of inflammatory bowel disease (IBD) has increased considerably during the past few decades.1 IBDs, composed of Crohn's disease (CD) and ulcerative colitis (UC), are characterized by heterogeneous presentation and widely variable clinical course. The therapeutic goals are to induce and maintain remission. Despite the current treatments available, many patients do not achieve this goal.

Nonbiologic Immune Suppression in Ulcerative Colitis.

This article reviews nonbiologic immunosuppressive agents in the induction and maintenance of remission of ulcerative colitis. Based on meta-analyses and North American guidelines, azathioprine, mercaptopurine, and methotrexate monotherapy are not recommended for induction therapy. Thiopurines are recommended in combination with infliximab. Tofacitinib has been shown to be an effective induction agent. Cyclosporine or tacrolimus are calcineurin inhibitors that can be used as induction therapy. Thiopurine monotherapy is suggested or recommended as maintenance therapy for patients who have achieved steroid-induced remission. Methotrexate monotherapy is not recommended. Tofacitinib has been shown to be an effective maintenance agent in moderate to severe disease.

Endoscopist-Directed Propofol as an Adjunct to Standard Sedation: A Canadian Experience.

BACKGROUND: Sedation practices vary widely by region. In Canada, endoscopist-directed administration of a combination of fentanyl and midazolam is standard practice. A minority of cases are performed with propofol. AIMS: To describe the safety of nonanaesthetist administered low-dose propofol as an adjunct to standard sedation. METHODS: This was a single-centre retrospective study of patients having undergone endoscopic procedures with propofol sedation between 2004 and 2012 in a teaching hospital in Montreal. Procedures were performed by gastroenterologists trained in Advanced Cardiovascular Life Support. Sedation was administered by intravenous bolus by a registered nurse, under the direction of the endoscopist. Outcomes of procedures were collected in the context of a retrospective chart review using the hospital's endoscopy database. RESULTS: Of patients undergoing endoscopies at our centre, 4930 patients received propofol as an adjunct to standard sedation with fentanyl and midazolam. Cecal intubation rate for colonoscopies (n = 2921) was 92.0%. Gastroscopies (n = 1614), flexible sigmoidoscopies (n = 28), endoscopic retrograde cholangiopancreatography (n = 331) and percutaneous endoscopic gastrostomy insertion (n = 36) had success rates, defined as successful completion of the procedure within anatomical limits, of 99.0, 96.4, 94.0 and 91.7%, respectively. The average dose of propofol used for each procedure was 34.5 ± 20.8 mg. Fentanyl was used in 67.4% of procedures at an average dose of 94.3 ± 17.5 mcg. Midazolam was used in 92.7% of cases at an average dose of 3.0 ± 0.7 mg. Reversal agents (naloxone or flumazenil) were used in 0.43% of the cases (n = 21). Patients who received propofol were discharged uneventfully within the usual postprocedure recovery time. One patient required sedation-related hospitalization. For patients having received propofol in addition to standard sedation agents, 99.6% experienced no adverse events. There were no mortalities. CONCLUSION: The use of low-dose propofol as an adjunct to fentanyl and midazolam, administered by a registered nurse under the direction of the endoscopist was safe and effective in patients at our centre.

Comparison of the Boston Bowel Preparation Scale with an Auditable Application of the US Multi-Society Task Force Guidelines.

BACKGROUND: Existing bowel preparation scales (BPS) only modestly predict interval to next colonoscopy. The US Multi-Society Task Force (MSTF) recommends repeating colonoscopies within the year if the preparation does not allow detection of polyps over 5 mm. AIM: This study aims to assess reliability and validity of an auditable application of the MSTF compared with the Boston BPS (BBPS). METHODS: We compared an auditable application of MSTF guidelines termed the Montreal BPS (MBPS) with the BBPS using a total cut-off score ≥6 with each segment score ≥2 (BBPS2-6). In sensitivity analyses, we applied the MBPS using a cut-off of 3 mm rather than 5 mm and also assessed the BBPS using an adequacy threshold of total score ≥5 (BBPS5). Videos of 83 colonoscopies (eight for intra-rater agreements) were independently evaluated by nine physicians. Weighted kappas quantified intra- and inter-rater agreements. Associations between scores and clinical outcomes were assessed. RESULTS: The BBPS2-6 and 5 mm MBPS showed moderate to substantial intra-rater agreements (κ=0.44 to 0.63 and κ=0.50 to 0.53, respectively); inter-rater agreements were only fair to moderate and slight to moderate (κ=0.25 to 0.48 and κ=0.19 to 0.50, respectively). Similar results were noted using alternate thresholds of BBPS5 and 3 mm MBPS. No significant associations were found between scores and clinical outcomes. CONCLUSION: For all scales, intra-rater kappas were superior to inter-rater values, the latter reflecting at best moderate agreement. This modest performance may reflect the dichotomized interpretation of the scales (adequate versus inadequate), differing from previous publications assessing scores as continuous variables. Further studies are required to optimally interpret bowel preparation scales with regard to interval to next colonoscopy.

Validating bowel preparation scales.

BACKGROUND AND STUDY AIM: Few scales assessing bowel preparation quality have been validated, and direct between-scale comparisons remain scarce. The aim of the study was to compare inter- and intra-rater reliability, predictive abilities for clinical outcomes, and ease of use for each scale. METHODS: Colonoscopy video recordings highlighting five colonic segments after washing were viewed independently by three physicians, and cleanliness was evaluated using the Boston Bowel Preparation Scale (BBPS), the Chicago Bowel Preparation Scale (CBPS), and the Harefield Cleansing Scale (HCS) in randomized order. Kappa or intraclass correlations quantified intra- and inter-rater reliability. Ease of use was evaluated (1 - 10 scale, 1 = easy), as were associations between scores, adenoma detection, and adequacy of preparation to exclude lesions ≥ 5 mm. RESULTS: Among 83 colonoscopy videos, indications included screening or surveillance in 72.3 %. Mean (±â€ŠSD) scores of the respective three raters were 5.17 ±â€Š1.57, 6.49 ±â€Š1.48, and 5.12 ±â€Š1.21 for BBPS, and 23.73 ±â€Š6.01, 28.39 ±â€Š5.47, and 24.75 ±â€Š5.83 for CBPS, while successful HCS scores (grade A or B) were given for 76 %, 89 %, and 63 % of examinations. Intra-rater reliability ranges were 0.88 - 1.00, 0.83 - 1.00, and 0.62 - 1.00 for BBPS, CBPS, and HCS, respectively. Similarly, inter-rater reliability ranges were 0.50 - 0.79, 0.64 - 0.83, and 0.28 - 0.52, respectively. Sources of disagreement included varying rater strictness, which was possibly most marked for preparations rated as intermediate. Overall, associations between preparation scores and adenoma detection lacked statistical significance. CONCLUSION: The BBPS and CBPS showed the best inter- and intra-rater reliability, and the BBPS was considered the easiest to use. Further studies are needed to determine an optimal adequacy threshold for these scales, with the goal of predicting clinical outcomes and determining the appropriate interval to the next colonoscopy.

Update on Therapeutic Drug Monitoring in Crohn's Disease.

In patients with Crohn's disease on biologic medications, the use of therapeutic drug monitoring leads to a personalized approach to optimize treatment. Using an algorithmic approach, measurement of drug concentrations and anti-drug antibodies can be used to improve treatment outcomes. Therapeutic drug concentrations and absence of antibodies are associated with improved clinical and endoscopic outcomes. In clinical practice, therapeutic drug monitoring has been shown to be clinically useful and cost-effective in patients experiencing a loss of response to treatment. This review highlights the available data on therapeutic drug monitoring in the treatment of patients with Crohn's disease on biologic medications.

Resected Hepatocellular Carcinoma in a Patient with Crohn's Disease on Azathioprine.

Hepatocellular carcinoma rarely occurs in patients without underlying cirrhosis or liver disease. While inflammatory bowel disease has been linked to certain forms of liver disease, hepatocellular carcinoma is exceedingly rare in these patients. We report the twelfth case of hepatocellular carcinoma in a patient with Crohn's disease. The patient is a 61-year-old with longstanding Crohn's disease who was treated with azathioprine and was found to have elevated liver enzymes and a new 3-cm liver mass on ultrasound. A complete workup for underlying liver disease was unremarkable and liver biopsy revealed hepatocellular carcinoma. The patient underwent a hepatic resection, and there is no evidence of recurrence at the 11-month follow-up. The resection specimen showed no evidence of cancer despite the initial biopsy revealing hepatocellular carcinoma. This case represents the third biopsy-proven complete spontaneous regression of hepatocellular carcinoma. Although large studies have failed to show a definite link between azathioprine and hepatocellular carcinoma, the relationship remains concerning given the multiple case reports suggesting a possible association. Clinicians should exercise a high degree of suspicion in patients with Crohn's disease who present with elevated liver enzymes, especially those on azathioprine therapy.