Safety and Efficacy of Reslizumab for Children and Adolescents With Eosinophilic Esophagitis Treated for 9 Years

Background: Eosinophilic esophagitis (EoE) is a chronic disease characterized by infiltration of eosinophils in the esophageal epithelium. There are limited treatment options for EoE. The rationale of the study was to evaluate the long-term safety and efficacy of reslizumab (RSZ) in pediatric patients who received RSZ in a randomized controlled trial (RCT) and expanded access program.

Methods: Records of patients who received RSZ in our center were reviewed. Patients received RSZ 2 mg/kg (or placebo) every 4 weeks as part of the RCT, open-label extension (OLE), and compassionate use (CU). Data were analyzed as of their most recent evaluation in August 2017. Labwork, history, and examinations were conducted every 12 weeks. Biopsy results were compared from baseline (before RCT) and at the most recent evaluation. Adverse events (AE) were recorded.

Results: Twelve patients entered the RCT at our center; 6 patients completed the OLE and 4 received RSZ through CU. Between the RCT, OLE, and CU periods, patients received 549 doses of RSZ (median 37, range 2-116). No serious AE were attributed to RSZ. Symptoms improved on treatment: dysphagia (42% vs 0%), abdominal pain (58% vs 0%), heartburn (18% vs 0%), vomiting (67% vs. 17%), reflux (58% vs. 0%). Median esophageal eosinophil count improved (35 eosinophils per high-power field vs 3, P < 0.001). Patients receiving RSZ maintain a relatively unrestricted diet.

Conclusions: RSZ appears to be safe in children with EoE over 9 years of treatment experience. Symptoms and eosinophil count improved considerably during treatment with RSZ despite a relatively unrestricted diet.