UNDERSTANDING REAL-WORLD BIOLOGIC MAINTENANCE DOSING PATTERNS AMONG PEDIATRIC ULCERATIVE COLITIS AND CROHN’S DISEASE PATIENTS

Abstract

Objectives To assess the initial and long-term maintenance dosing ofbiologic medications in pediatric UC and CD patients, using datain the ICN registry. Methods Pediatric patients (2-17 years) in the US who were diagnosedwith UC or CD between June 1, 2013 and December 31, 2019, who,after enrollment in the ICN registry, initiated a biologic(adalimumab, infliximab, certolizumab, golimumab,ustekinumab, vedolizumab, and natalizumab) and were activelyfollowed for at least 12 months after first maintenance dosewere included in this study. Descriptive statistics of baselinepatient demographics were summarized for the overallInflammatory Bowel Disease (IBD) patient population andseparately for UC and CD. Biologic maintenance dosage wascalculated for UC and CD patients who had data for both doseand weight for each biologic at the baseline visit (firstmaintenance dose), 1-year and 3-year time points. Results A total of 1,887 pediatric IBD patients (UC=350; CD=1,537) wereincluded in this study. Patients had a mean age at diagnosis of12.9 years (UC=13.1; CD=12.9), 57.1% were male (UC=48.9%;CD=59.0%), and 80.6% were White (UC=79.8%; CD=80.8%)(Table 1). Infliximab (77.0%) was the most commonlyprescribed biologic for UC, followed by adalimumab (12.4%),vedolizumab (10.1%), certolizumab (0.3%), and ustekinumab(0.3%). Similarly, infliximab (80.6%) was the most commonlyprescribed biologic for CD, followed by adalimumab (16.5%),vedolizumab (1.6%), ustekinumab (1.2%), and certolizumab(0.1%) (Table 2). At first maintenance dose, UC patients on infliximab werereceiving a mean dose of 10.5mg/kg/8wk, patients onadalimumab (weight <40kg) were receiving a mean dose of1.3mg/kg/2wk, patients on adalimumab (weight>=40kg) werereceiving a mean dose of 0.8mg/kg/2wk, and patients onvedolizumab were receiving a mean dose of 6.9mg/kg/8wks.Mean dose of infliximab among UC patients increased from10.5mg/kg/8wk at first maintenance dose to 11.8mg/kg/8wk at1-year from first maintenance dose. At the first maintenance dose, CD patients on infliximab werereceiving a mean dose of 8.1mg/kg/8wk, patients onadalimumab (weight <40kg) were receiving a mean dose of1.1mg/kg/2wk, patients on adalimumab (weight >=40kg) werereceiving a mean dose of 0.8mg/kg/2wk, patients receivingvedolizumab were receiving a mean dose of 10.5mg/kg/8wks.Mean dose of infliximab among CD patients increased from8.1mg/kg/8wk at first maintenance dose to 9.6mg/kg/8wk at 1-year from first maintenance dose. Conclusion These results highlight the biologic maintenance dose changesamong pediatric UC and CD patients. TNF inhibitors remain themost commonly used class of biologic, but the doses being usedare double the standard dosing guidelines. There is littleevidence of dose reduction over time among pediatric UC and CDpatients in the ICN registry.