Proactive therapeutic drug monitoring and vedolizumab dose optimization in children with inflammatory bowel disease.

OBJECTIVES: Therapeutic drug monitoring (TDM) and dose optimization have been shown to improve clinical outcomes with antitumor necrosis factor and recent studies in adults suggest an exposure-response relationship with drug levels associated with improved clinical outcomes. However, these levels are not universally recognized as therapeutic targets for vedolizumab dosing. We aimed to assess the impact of a TDM quality improvement (QI) initiative on 52-week clinical outcomes and describe proactively obtained vedolizumab levels during the induction period in children with inflammatory bowel disease (IBD). METHODS: A QI initiative to proactively obtain TDM levels at Week 6 was implemented in 2019. A retrospective review of pediatric patients with IBD treated with vedolizumab from 2018 to 2022 was performed. Baseline demographic data, medication dosing details, disease characteristics, lab results, and 12-month clinical outcomes were recorded. For this study, we defined therapeutic target levels (>20 µg/mL at Week 6 and >12 µg/mL during maintenance) based on existing data correlating these levels with improved clinical outcomes. RESULTS: Fifty-nine patients (31 Crohn disease [CD], 28 ulcerative colitis [UC]/indeterminate colitis [IC]) were included in the study. In total, 68% (40/59) of patients had vedolizumab levels at Week 6 and 90% (53/59) had levels drawn at Week 6 or 14. Thirty-five percent of Week 6 trough levels were below our defined target of 20 µg/mL. Fifty-two of 59 patients had available data at 52 weeks. Over 80% (42/52) of patients remained on vedolizumab 52 weeks after initiation (CD 79% [23/29], UC/IC 83% [19/23]). Sixty-two percent (26/42) of patients that remained on vedolizumab at 52 weeks were treated with an intensified dosing interval of <8 weeks. Thirty-one of these 42 (74%) were in clinical remission (CR) rate at 52 weeks with 29/42 (69%) in corticosteroid-free remission. The CR rate for the entire cohort including those who discontinued therapy due to a lack of efficacy before 52 weeks was 60% (31/52). CONCLUSION: Proactive TDM and early dose optimization with vedolizumab may improve drug durability and clinical outcomes in pediatric patients with IBD.

Mucosal transcriptomics highlight lncRNAs implicated in ulcerative colitis, Crohn's disease, and celiac disease.

Ulcerative colitis (UC), Crohn's disease (CD), and celiac disease are prevalent intestinal inflammatory disorders with nonsatisfactory therapeutic interventions. Analyzing patient data-driven cohorts can highlight disease pathways and new targets for interventions. Long noncoding RNAs (lncRNAs) are attractive candidates, since they are readily targetable by RNA therapeutics, show relative cell-specific expression, and play key cellular functions. Uniformly analyzing gut mucosal transcriptomics from 696 subjects, we have highlighted lncRNA expression along the gastrointestinal (GI) tract, demonstrating that, in control samples, lncRNAs have a more location-specific expression in comparison with protein-coding genes. We defined dysregulation of lncRNAs in treatment-naive UC, CD, and celiac diseases using independent test and validation cohorts. Using the Predicting Response to Standardized Pediatric Colitis Therapy (PROTECT) inception UC cohort, we defined and prioritized lncRNA linked with UC severity and prospective outcomes, and we highlighted lncRNAs linked with gut microbes previously implicated in mucosal homeostasis. HNF1A-AS1 lncRNA was reduced in all 3 conditions and was further reduced in more severe UC form. Similarly, the reduction of HNF1A-AS1 ortholog in mice gut epithelia showed higher sensitivity to dextran sodium sulfate-induced colitis, which was coupled with alteration in the gut microbial community. These analyses highlight prioritized dysregulated lncRNAs that can guide future preclinical studies for testing them as potential targets.

Single-Center Analysis of Essential Laboratory Testing in Patients with Newly Diagnosed Celiac Disease.

OBJECTIVE: To analyze laboratory testing results from pediatric patients newly diagnosed with celiac disease to determine the usefulness of each test derived from recommended guidelines. METHODS: Serological testing at the time of diagnosis from patients enrolled in our celiac disease registry from January 2018 through December 2021 was reviewed. The incidence of abnormal laboratory results, routinely obtained as per the recommendations of Snyder et al and our institution's Celiac Care Index, was assessed. Rates of abnormal laboratory values and estimated costs associated with these screening measures were analyzed. RESULTS: Our data demonstrated abnormalities in all serological testing obtained at celiac diagnosis. Hemoglobin, alanine aminotransferase, ferritin, iron, and vitamin D screening were found to be abnormal with notable frequency. Only 7% of patients had an abnormal thyroid-stimulating hormone and <0.1% had an abnormal free T4. Nonresponse to hepatitis B vaccination was prominent, with 69% of patients considered nonimmune. Screening protocols as currently outlined in our Celiac Care Index resulted in an estimated cost of approximately $320 000 during our study. CONCLUSIONS: Review of screening laboratory results at our center reveals that abnormal values for several recommended measures are uncommon. Thyroid screening was infrequently abnormal and the usefulness of screening for hepatitis B at diagnosis is uncertain. Similarly, our data suggest that iron deficiency screening may be condensed effectively into hemoglobin and ferritin testing, eliminating the need for initial iron studies. Decreasing baseline screening measures could safely decrease the burden of testing on patients and overall healthcare expenditures.

Comparative Effectiveness of Anti-TNF in Combination With Low-Dose Methotrexate vs Anti-TNF Monotherapy in Pediatric Crohn's Disease: A Pragmatic Randomized Trial.

BACKGROUND & AIMS: Tumor necrosis factor inhibitors, including infliximab and adalimumab, are a mainstay of pediatric Crohn's disease therapy; however, nonresponse and loss of response are common. As combination therapy with methotrexate may improve response, we performed a multicenter, randomized, double-blind, placebo-controlled pragmatic trial to compare tumor necrosis factor inhibitors with oral methotrexate to tumor necrosis factor inhibitor monotherapy. METHODS: Patients with pediatric Crohn's disease initiating infliximab or adalimumab were randomized in 1:1 allocation to methotrexate or placebo and followed for 12-36 months. The primary outcome was a composite indicator of treatment failure. Secondary outcomes included anti-drug antibodies and patient-reported outcomes of pain interference and fatigue. Adverse events (AEs) and serious AEs (SAEs) were collected. RESULTS: Of 297 participants (mean age, 13.9 years, 35% were female), 156 were assigned to methotrexate (110 infliximab initiators and 46 adalimumab initiators) and 141 to placebo (102 infliximab initiators and 39 adalimumab initiators). In the overall population, time to treatment failure did not differ by study arm (hazard ratio, 0.69; 95% CI, 0.45-1.05). Among infliximab initiators, there were no differences between combination and monotherapy (hazard ratio, 0.93; 95% CI, 0.55-1.56). Among adalimumab initiators, combination therapy was associated with longer time to treatment failure (hazard ratio, 0.40; 95% CI, 0.19-0.81). A trend toward lower anti-drug antibody development in the combination therapy arm was not significant (infliximab: odds ratio, 0.72; 95% CI, 0.49-1.07; adalimumab: odds ratio, 0.71; 95% CI, 0.24-2.07). No differences in patient-reported outcomes were observed. Combination therapy resulted in more AEs but fewer SAEs. CONCLUSIONS: Among adalimumab but not infliximab initiators, patients with pediatric Crohn's disease treated with methotrexate combination therapy experienced a 2-fold reduction in treatment failure with a tolerable safety profile. CLINICALTRIALS: gov, Number: NCT02772965.

Biosimilars for Pediatric Patients With Inflammatory Bowel Disease: Pediatric Gastroenterology Clinical Practice Survey.

BACKGROUND: Biosimilars are biological agents that have been demonstrated to have similar safety and efficacy profiles as the originator. The objective of this study was to evaluate the perspectives of pediatric gastroenterologists in the United States (U.S.) toward biosimilar use and to explore factors that impact their comfort level with prescribing infliximab biosimilars. METHODS: A cross-sectional survey was developed and distributed to pediatric gastroenterology physicians from the U.S. via a listserv (Pediatric gastroenterology Bulletin Board). Respondent's demographics were recorded. Using a 6-point Likert scale, the survey assessed the respondent's perceptions toward biosimilars and initiating switches from the originator to biosimilar agent along with factors impacting provider's comfort level. Fischer exact tests were used to detect statistically significant differences in responses for hypotheses of interest. RESULTS: One hundred thirty-nine pediatric gastroenterologists completed the online survey (response rate 5.4%). Eighty-seven percent of respondents reported being comfortable prescribing infliximab biosimilars to anti-tumor necrosis factor naive patients, and 69% reported being comfortable doing a one-time switch if the patient was in clinical remission. Factors that negatively impacted a respondent's comfort level included respondents not practicing at an ImproveCareNow (ICN) center and managing less than 50 patients with inflammatory bowel diseases (IBD). CONCLUSIONS: Nearly 90% of pediatric gastroenterologists felt comfortable prescribing an infliximab biosimilar, and 70% felt comfortable with a one-time switch to the biosimilar if the patient was in clinical remission. Involvement in ICN a learning health system and caring for higher numbers of patients with IBD was associated with increased provider comfort with biosimilar use.

Diagnosis and Treatment of Iron Deficiency and Anemia in Youth With Inflammatory Bowel Disease.

OBJECTIVES: Iron deficiency (ID) with and without anemia is prevalent in children and adults diagnosed with inflammatory bowel disease (IBD), but often goes unrecognized. We hypothesized, quality improvement (QI) methodology could increase the screening for and treatment of ID in children newly diagnosed with IBD. METHODS: We developed and implemented an easy-to-follow algorithm to facilitate screening for and treatment of ID for patients diagnosed with IBD. Through a series of Plan-Do-Study-Act cycles, the approach was modified to increase screening and treatment of ID. Data between January 2019 and July 2021 were assessed using statistical process control. RESULTS: Among patients newly diagnosed with IBD, 298 patients were included (67% Crohn disease, 29% ulcerative colitis, 4% indeterminate colitis, and 56% males). Rates of ID screening increased significantly from a baseline of 20% to >90%. Of the 232 patients screened for ID during the improvement period, 205 (88%) met criteria for either iron deficiency anemia (IDA) or ID at diagnosis, specifically, 151 (65%) met criteria for IDA and 54 (23%) met criteria for ID. CONCLUSIONS: Use of QI methodology to standardize screening assessments for ID among children newly diagnosed with IBD improved screening rates from a baseline of 20% to >90%, with 88% of patients found to have IDA or ID.

Improving Hepatitis B Vaccination Rates among At-risk Children and Adolescents with Inflammatory Bowel Disease.

Patients with inflammatory bowel disease (IBD) receiving tumor necrosis factor alpha inhibitors (TNFai) may be at higher risk for hepatitis B virus (HBV) infection. We conducted a quality improvement (QI) initiative to improve HBV vaccination rates in seronegative children with IBD. Methods: This QI initiative implemented an HBV vaccination strategy from September 2018 to March 2020 in patients with newly diagnosed IBD with hepatitis B surface antibody (HBsAb) <10 mIU/mL. The project aimed to (1) increase HBV vaccination rates in seronegative patients and (2) document immunogenicity after completing a three-dose vaccine series. Outcome measures included the percentage of seronegative patients who received HBV vaccines (dose 1 and three-dose series). Interventions included applying a standardized vaccination protocol, and creating a vaccine workflow in two clinical areas, previsit planning and stakeholder engagement. Results: One hundred seventy-four children and adolescents with IBD were evaluated during the study period, and 132 (76%) were HBsAb negative. After plan-do-study-act (PDSA) 1, the proportion of eligible patients who received HBV vaccine dose 1 increased from a baseline of 7% to 100% and was sustained for over 12 months. During PDSA 2, the proportion of patients completing the three-dose vaccine series improved from a baseline of 0% to 82% (n = 100); among 93 children in this subgroup who had repeat serology performed, 86 (92%) demonstrated serologic evidence of HBV protection. Conclusions: A multidisciplinary approach applying QI methodology allowed for improved and sustained HBV vaccination rates in at-risk seronegative children and adolescents with IBD. A three-dose HBV vaccine series proved immunogenic in 92% of eligible patients.

6- and 12-Month Outcomes after 90:10 Enteral Nutrition Induction Therapy in Pediatric Crohn's Disease.

OBJECTIVES: Studies describing longer-term outcomes after EEN induction are limited. We describe clinical outcomes during 90:10 EN induction, and 6- and 12- month outcomes among patients that successfully completed EN induction and then continued either EN or immunomodulator (IM) maintenance therapy. METHODS: All children with CD treated with 90:10 EN induction protocol (90% formula:10% regular diet) at our IBD Center from 2013 to 2018 were retrospectively reviewed. Demographic, clinical, and laboratory data were recorded at baseline, 6, and 12 months (± 3 months at each timepoint). Therapy changes after initiation of EN induction through 12 months were recorded. Among patients that successfully completed 90:10 induction, outcomes between EN and IM maintenance groups were compared. RESULTS: In total, 44/105 (42%) patients completed 8-12 weeks of 90:10 EN induction. Sixty-one patients had incomplete EN induction, with 52% requiring corticosteroids and 25% anti-TNF therapy as alternate induction approaches. Forty-four patients completed EN induction (18 continued EN maintenance and 26 IM maintenance therapy). Twenty-seven of these 44 (61%) remained on initial maintenance therapy at 6 months (10/18 (56%) EN and 17/26 (65%) IM). In total, 16/44 (36%) remained on their initial maintenance therapy at 12 months. By 12 months, 10 patients required anti-TNF and 11 corticosteroids after successful completion of induction. CONCLUSIONS: In this retrospective study of short and longer-term outcomes after 90:10 EN induction, the need for an alternate induction therapy was common, most frequently to anti-TNF or corticosteroid therapy. Future studies are needed to evaluate for predictors of long-term success after EN induction.

Personalized Research on Diet in Ulcerative Colitis and Crohn's Disease: A Series of N-of-1 Diet Trials.

INTRODUCTION: Evidence about specific carbohydrate diet (SCD) for inflammatory bowel disease (IBD) is limited. We conducted 54 single-subject, double-crossover N-of-1 trials comparing SCD with a modified SCD (MSCD) and comparing each with the participant's baseline, usual diet (UD). METHODS: Across 19 sites, we recruited patients aged 7-18 years with IBD and active inflammation. Following a 2-week baseline (UD), patients were randomized to 1 of 2 sequences of 4 alternating 8-week SCD and MSCD periods. Outcomes included fecal calprotectin and patient-reported symptoms. We report posterior probabilities from Bayesian models comparing diets. RESULTS: Twenty-one (39%) participants completed the trial, 9 (17%) completed a single crossover, and 24 (44%) withdrew. Withdrawal or early completion occurred commonly (lack of response [n = 11], adverse events [n = 11], and not desiring to continue [n = 6]). SCD and MSCD performed similarly for most individuals. On average, there was <1% probability of a clinically meaningful difference in IBD symptoms between SCD and MSCD. The average treatment difference was -0.3 (95% credible interval -1.2, 0.75). There was no significant difference in the ratio of fecal calprotectin geometric means comparing SCD and MSCD (0.77, 95% credible interval 0.51, 1.10). Some individuals had improvement in symptoms and fecal calprotectin compared with their UD, whereas others did not. DISCUSSION: SCD and MSCD did not consistently improve symptoms or inflammation, although some individuals may have benefited. However, there are inherent difficulties in examining dietary changes that complicate study design and ultimately conclusions regarding effectiveness.

Patient and Caregivers' Perspectives on Biosimilar Use in Pediatric Inflammatory Bowel Disease.

BACKGROUND: Studies assessing adult inflammatory bowel disease (IBD) patient perspectives on biosimilar use revealed that most were unfamiliar with biosimilars and had a negative perception. The objective of this study was to evaluate the perspectives of pediatric patients with IBD and their caregivers regarding biosimilar use and non-medical switches. METHODS: A survey was given to a cross section of patients with IBD ages 11-21 years receiving the intravenous anti-tumor necrosis factor originator and caregivers of patients with IBD ages 3-21 years receiving the originator. Recruitment occurred via mail, during clinic visits, and infusions. Fisher exact tests were used to test for statistically significant differences. RESULTS: Response rate amongst caregivers was 49% (n = 98) and among patients was 35% (n = 67). Sixty-four percent of caregivers and 79% of patients had never heard of biosimilars. There was increased discomfort surrounding the use of biosimilars and switching to a biosimilar amongst caregivers who had previously heard of biosimilars compared to caregivers who had not previously heard of biosimilars ( P < 0.05). Similar concerns were not seen in patient respondents. The length of time on the originator had no effect on patient or caregiver concerns related to biosimilar efficacy, adverse effects, or switches. CONCLUSION: The majority of pediatric patients and caregivers had never heard of biosimilars. Caregivers that had heard of biosimilars before the study were more likely to have a negative perception of them. This study highlights the importance of providing thorough and accurate education to pediatric patients and families regarding the safety and efficacy of biosimilars.

Risk of Post-Resection Recurrence in Pediatric Crohn Disease.

BACKGROUND: Ileocecectomy related to stricturing, fistula formation, or medically refractory disease is commonly required in patients with Crohn disease (CD). Limited research exists in endoscopic recurrence (ER) in pediatric inflammatory bowel disease (IBD). In this study, we sought to determine ER rates and the impact of therapy duration before surgery in pediatric patients with CD. METHODS: This was a single-center retrospective review of patients with CD between the ages of 2 to 20 years who required ileocecectomy between January 2015 and December 2019 at Nationwide Children's Hospital. Follow-up endoscopies, laboratory values, medications, and sPCDAI scores were recorded at 6, 12, 24, and 36 months post-resection wherever available. Modified Rutgeert scores (mRS) were independently assigned to post-resection colonoscopy images by 3 trained investigators. Post-resection outcomes were compared between patients on CD therapy >30 days before resection (late surgery) to those started on CD therapy <30 days before resection (early surgery). RESULTS: A total of 48 patients underwent ileocecectomy, with a mean age at time of resection of 17 years (+/-2.3). In total, 88% of patients had a post-resection endoscopy and 57% had an endoscopy within 12 months of resection. Twenty-nine percentage had ER with a mRS ≥i2. There was no statistical difference in endoscopic and clinical outcomes after resection between the early and late surgery groups. CONCLUSIONS: Post-resection endoscopic recurrence after ileocecectomy was found in 29% of our center's pediatric CD population based on mRS. Post-resection outcomes were not affected by therapy duration before resection.

Increasing Biosimilar Utilization at a Pediatric Inflammatory Bowel Disease Center and Associated Cost Savings: Show Me the Money.

BACKGROUND: Tumor necrosis factor-alpha inhibitors (anti-TNFs) are a primary treatment for inflammatory bowel disease. Pharmaceutical expenditures and usage of specialty drugs are increasing. In the United States, biosimilars continue to be underutilized, despite opportunities for health care cost savings. Through quality improvement (QI) methodology, we aimed to increase biosimilar utilization among eligible patients initiating intravenous (IV) anti-TNF therapy and describe patient outcomes and associated cost savings. METHODS: Beginning in July 2019, all patients initiating IV anti-TNF therapy were identified and tracked. Using the Institute of Healthcare Improvement Plan-Do-Study-Act cycle, a four-stage problem-solving model used for carrying out change, we trialed interventions to increase biosimilar utilization, including provider, staff, and family education, and utilization of a clinical pharmacist and insurance specialist. Statistical process control charts were used to show improvement over time. Patients' clinical outcome and cost savings were reviewed. RESULTS: Using QI methodology, we increased biosimilar utilization from a baseline of 1% in June 2019 to 96% by February 2021, with sustained improvement. The originator (infliximab) was the insurance company's preferred product for 20 patients (20%). Patient outcomes (IV anti-TNF levels, absence of antidrug antibodies, and physician global assessment) between biosimilars and originators were similar. Estimated cost savings over the project duration were nearly $381,000 (average sales price) and $651,000 (wholesale acquisition cost). CONCLUSIONS: Through QI methodology, we increased biosimilar utilization from 1% to 96% with sustained improvement, without compromising patient outcomes or safety. Estimated cost savings were substantial. Similar methodology could be implemented at other institutions to increase biosimilar utilization and potentially decrease health care costs.

Early Change in Fecal Calprotectin Predicts One-Year Outcome in Children Newly Diagnosed With Ulcerative Colitis.

INTRODUCTION: While fecal calprotectin (FC) is used to assess disease activity in ulcerative colitis (UC) there are little data concerning the role of serial FC levels at diagnosis in predicting clinical course. We sought to determine whether FC at diagnosis or early change following therapy predicts clinical outcomes in pediatric UC.Methods: Children with newly diagnosed UC were treated with standardized regimens of mesalamine or corticosteroids (CS). CS tapering and escalation to additional therapy or colectomy were by protocol. Patients with baseline or week 4 or week 12 FC levels were included in the analysis. Our primary outcome was CS-free remission on mesalamine at week 52. We compared the prognostic value of a baseline FC as well as a change in FC by week 4 or week 12 in predicting clinical outcomes. RESULTS: The study included 352 children (113 initial mesalamine, 239 initial CS, mean age 12.6 years) with UC. At Week 52, 135 (38.3%), 84 (23.8%), and 19 (5.4%) children achieved CS-free remission, needed anti-tumor necrosis factor therapy or had colectomy respectively. Baseline FC was not associated with CS-free remission at week 52. However, both week 4 (odds ratio [OR] 0.95, 95% confidence interval [CI] 0.901.00) and week 12 FC levels (OR 0.91, 95% CI 0.87-0.96) were associated with outcomes, with the latter having a stronger association with CS-free remission. Patients with a >75% decrease by 12 weeks, had a 3-fold increased likelihood of CS-free remission at 1 year. DISCUSSION: Longitudinal changes in FC may predict 1 year outcomes better than values at diagnosis in children with a new diagnosis of UC.

Antibodies-to-infliximab accelerate clearance while dose intensification reverses immunogenicity and recaptures clinical response in paediatric Crohn's disease.

BACKGROUND: Antibodies to infliximab (ATI) are associated with secondary loss of response and increased risk for drug reactions. Limited studies have associated ATI with increased infliximab clearance. AIMS: We assessed the impact of ATI on infliximab clearance and loss of response in an inception paediatric Crohn's disease cohort with 1-year follow-up. METHODS: This multi-centre prospective cohort study collected peak and trough serum infliximab/ATI concentrations from 660 infusions (78 patients) during the first year of therapy. Clinicians were blinded to these research labs. The primary outcome was the difference in infliximab clearance between ATI-positive (ATI) and ATI-negative (no-ATI) patients. Secondary outcomes included pre-treatment predictors of ATI (including HLA-DQA1 genotyping). Clinical remission, loss of response and infliximab clearance were compared between pre-ATI, during ATI and following ATI resolution with MANOVA. Time to ATI was calculated by Cox proportional Hazards model. RESULTS: ATI were detected in 68% (53/78) patients with a median concentration of 76 ng/mL (range 23-1828). Maximum ATI concentration was <200 ng/mL in 73.6% (39/53). Median clearance in ATI patients was higher (with higher clearance if loss of response), compared to no-ATI patients (P < 0.001). Neutrophil CD64 ratio >6 and starting dose <7.5 mg/kg independently predicted ATI in multivariable regression, while HLA-DQA1*05 presence did not. Dose adjustment resolved ATI in 37.5% (12/32) patients with concomitant infliximab concentration and clearance recovery. A maximum ATI level of ≤99 ng/mL predicted ATI resolution (area under the receiver operating curve 0.80 [95% CI 0.64-0.96]). CONCLUSIONS: In this real-world cohort, ATI as low as 23 ng/mL impacted drug clearance. Our data suggest that dose optimisation for low-level ATI can improve infliximab clearance and prevent loss of response.

Stratification of risk of progression to colectomy in ulcerative colitis via measured and predicted gene expression.

An important goal of clinical genomics is to be able to estimate the risk of adverse disease outcomes. Between 5% and 10% of individuals with ulcerative colitis (UC) require colectomy within 5 years of diagnosis, but polygenic risk scores (PRSs) utilizing findings from genome-wide association studies (GWASs) are unable to provide meaningful prediction of this adverse status. By contrast, in Crohn disease, gene expression profiling of GWAS-significant genes does provide some stratification of risk of progression to complicated disease in the form of a transcriptional risk score (TRS). Here, we demonstrate that a measured TRS based on bulk rectal gene expression in the PROTECT inception cohort study has a positive predictive value approaching 50% for colectomy. Single-cell profiling demonstrates that the genes are active in multiple diverse cell types from both the epithelial and immune compartments. Expression quantitative trait locus (QTL) analysis identifies genes with differential effects at baseline and week 52 follow-up, but for the most part, differential expression associated with colectomy risk is independent of local genetic regulation. Nevertheless, a predicted polygenic transcriptional risk score (PPTRS) derived by summation of transcriptome-wide association study (TWAS) effects identifies UC-affected individuals at 5-fold elevated risk of colectomy with data from the UK Biobank population cohort studies, independently replicated in an NIDDK-IBDGC dataset. Prediction of gene expression from relatively small transcriptome datasets can thus be used in conjunction with TWASs for stratification of risk of disease complications.

Real-World Infliximab Pharmacokinetic Study Informs an Electronic Health Record-Embedded Dashboard to Guide Precision Dosing in Children with Crohn's Disease.

Standard-of-care infliximab dosing regimens were developed prior to the routine use of therapeutic drug monitoring and identification of target concentrations. Not surprisingly, subtherapeutic infliximab concentrations in pediatric Crohn's disease (CD) are common. The primary aim was to conduct a real-world pharmacokinetic (PK) evaluation to discover blood biomarkers of rapid clearance, identify exposure targets, and a secondary aim to translate PK modeling to the clinic. In a multicenter observational study, 671 peak and trough infliximab concentrations from 78 patients with CD were analyzed with a drug-tolerant assay (Esoterix; LabCorp, Calabasas, CA). Individual area under the curve (AUC) estimates were generated as a measure of drug exposure over time. Population PK modeling (nonlinear mixed-effect modeling) identified serum albumin, antibody to infliximab, erythrocyte sedimentation rate (ESR), and neutrophil CD64 as biomarkers for drug clearance. Week 14 and week 52 biochemical remitters (fecal calprotectin < 250 µg/g) had higher infliximab exposure (AUC) throughout induction. The optimal infliximab AUC target during induction for week 14 biochemical remission was 79,348 µg*h/mL (area under the receiver operating characteristic curve (AUROC) 0.77, [0.63-0.90], 85.7% sensitive, and 64.3% specific) with those exceeding the AUC target more likely to achieve a surgery-free week 52 biochemical remission (OR 4.3, [1.2-14.6]). Pretreatment predictors for subtherapeutic week 14 AUC included neutrophil CD64 > 6 (OR 4.5, [1.4-17.8]), ESR > 30 mm/h (OR 3.8, [1.4-11]), age < 10 years old (OR 4.2, [1.2-20]), and weight < 30 kg (OR 6.6, [2.1-25]). We created a decision-support PK dashboard with an iterative process and embedded the modeling program within the electronic health record. Model-informed precision dosing guided by real-world PKs is now available at the bedside in real-time.

Achieving Target Infliximab Drug Concentrations Improves Blood and Fecal Neutrophil Biomarkers in Crohn's Disease.

BACKGROUND: The neutrophil fecal biomarkers, calprotectin (FCP) and lactoferrin (LCT), and peripheral blood neutrophil CD64 surface receptor (nCD64) are biomarkers for mucosal inflammation in inflammatory bowel disease (IBD). Although FCP has been evaluated as a biomarker for mucosal healing, cut points for LCT and nCD64 are less known. We aimed to identify the cut points for LCT and nCD64 that were associated with FCP remission, with a secondary aim to evaluate the relationship between biochemical outcomes and infliximab (IFX) trough concentrations. METHODS: We analyzed FCP, LCT, and nCD64 before and after IFX induction in a pediatric Crohn's disease (CD) cohort study. Week-14 FCP biomarker remission was defined as FCP <250 µg/g, with clinical response defined as a weighted Pediatric Crohn's Disease Activity Index <12.5 or Δ>17.5 improvement. Predictive outcomes were calculated by receiver operating characteristics (ROCs). RESULTS: Among 56 CD patients, ROC analysis identified an infusion 4 LCT <8.06 (area under the receiver operator characteristics [AUROC], 0.934, P < 0.001) and nCD64 <6.12 (AUROC, 0.76, P = 0.02) as the ideal cut points for week-14 FCP biomarker remission. End of induction IFX-trough of >9.4 µg/mL (AUROC, 0.799, P = 0.002) and >11.5 µg/mL (AUROC, 0.835, P = 0.003) were associated with a FCP <250 and FCP <100, respectively. We found patients achieving end of induction trough >5 µg/mL had a median FCP improvement (dose 1 to dose 4) of 90% compared with a median of 35% with levels <5 µg/mL (P = 0.024) with a similar median reduction in nCD64 (48% vs 20%, P = 0.031). CONCLUSIONS: This study establishes cut points in neutrophil stool and blood biomarkers for both biochemical remission and therapeutic trough levels following induction therapy. Further studies that evaluate pharmacodynamic biomarker targets for endoscopic and histologic healing are warranted.

Analysis of Using the Total White Blood Cell Count to Define Severe New-onset Ulcerative Colitis in Children.

OBJECTIVES: The aim of this study was to assess common laboratory tests in identifying severe ulcerative colitis in children at diagnosis. METHODS: A cohort of 427 children 4 to 17 years of age newly diagnosed with ulcerative colitis (UC) was prospectively enrolled. Boosted classification trees were used to characterize predictive ability of disease attributes based on clinical disease severity using Pediatric Ulcerative Colitis Activity Index (PUCAI), severe (65+) versus not severe (<65) and total Mayo score, severe (10-12) versus not severe (<10); mucosal disease by Mayo endoscopic subscore, severe (3) versus not severe (<3); and extensive disease versus not extensive (left-sided and proctosigmoiditis). RESULTS: Mean age was 12.7 years; 49.6% (n = 212) were girls, and 83% (n = 351) were Caucasian. Severe total Mayo score was present in 28% (n = 120), mean PUCAI score was 49.8 ±â€Š20.1, and 33% (n = 142) had severe mucosal disease with extensive involvement in 82% (n = 353). Classification and regression trees identified white blood cell count, erythrocyte sedimentation rate, and platelet count (PLT) as the set of 3 best blood laboratory tests to predict disease extent and severity. For mucosal severity, albumin (Alb) replaced PLT. Classification models for PUCAI and total Mayo provided sensitivity of at least 0.65 using standard clinical cut-points with misclassification rates of approximately 30%. CONCLUSIONS: A combination of the white blood cell count, erythrocyte sedimentation rate, and either PLT or albumin is the best predictive subset of standard laboratory tests to identify severe from nonsevere clinical or mucosal disease at diagnosis in relation to objective clinical scores.

Continued Statural Growth in Older Adolescents and Young Adults With Crohn's Disease and Ulcerative Colitis Beyond the Time of Expected Growth Plate Closure.

BACKGROUND: Cessation of statural growth occurs with radiographic closure of the growth plates, radiographically defined as bone age (BA) 15 years in females and 17 in males. METHODS: We determined the frequency of continued growth and compared the total height gain beyond the time of expected growth plate closure and the chronological age at achievement of final adult height in Crohn's disease (CD) vs ulcerative colitis (UC) and described height velocity curves in inflammatory bowel disease (IBD) compared with children in the National Health and Nutrition Examination Survey (NHANES). We identified all females older than chronological age (CA) 15 years and males older than CA 17 years with CD or UC in the ImproveCareNow registry who had height documented at ≥3 visits ≥6 months apart. RESULTS: Three thousand seven patients (48% female; 76% CD) qualified. Of these patients, 80% manifested continued growth, more commonly in CD (81%) than UC (75%; P = 0.0002) and in females with CD (83%) than males with CD (79%; P = 0.012). Median height gain was greater in males with CD (1.6 cm) than in males with UC (1.3 cm; P = 0.0004), and in females with CD (1.8 cm) than in females with UC (1.5 cm; P = 0.025). Height velocity curves were shifted to the right in patients with IBD vs NHANES. CONCLUSIONS: Pediatric patients with IBD frequently continue to grow beyond the time of expected growth plate closure. Unexpectedly, a high proportion of patients with UC exhibited continued growth, indicating delayed BA is also common in UC. Growth, a dynamic marker of disease status, requires continued monitoring even after patients transition from pediatric to adult care.