S4372 Recurrence of Eosinophilic Esophagitis in a Patient Inadequately Treated With Off-Label Maintenance Dosing of Budesonide Oral Suspension

Introduction: Eosinophilic esophagitis (EoE) is a chronic type 2 inflammatory disease requiring maintenance therapy. Budesonide oral suspension (BOS) is an FDA-approved formulation of the topical corticosteroid (TCS) that is prepackaged at 2 mg per 10 mL in single-dose stick packs. Prior to BOS, oral viscous budesonide (OVB) was used off-label for EoE and often prepared by patients using a thickening agent. While TCS is effective for EoE, maintenance dosing remains unclear. Access to TCS is also challenging, often due to approval issues and cost. Herein, we describe a case of EoE recurrence in a patient on off-label BOS at 0.5 mg daily, who was previously well controlled on the same daily OVB maintenance dose. Case Description/Methods: A 66-year-old man was previously diagnosed with EoE when esophagogastroduodenoscopy, performed for dysphagia, showed a narrow-caliber esophagus; biopsies revealed 50 eosinophils (eos)/high-power field (hpf). Despite high-dose proton pump inhibitors, fibrostenotic EoE progressed, status post esophageal dilation to 10 mm. OVB was initiated at 2 mg twice daily with histologic remission and luminal improvement to 15 mm. Combining OVB and serial dilations, esophageal luminal diameter reached 20 mm. Therapy was transitioned to OVB monotherapy. Over 1 year, OVB was titrated to 0.5 mg daily, guided by serial endoscopic evaluations. He was maintained on OVB at 0.5 mg daily, with sustained clinical, endoscopic and histologic deep remission. Following FDA approval of BOS for EoE, TCS was switched to BOS. After 3 months on off-label BOS at 0.5 mg daily, his EoE recurred, with associated dysphagia. esophagogastroduodenoscopy showed edema, rings, and a 17-mm stricture (E1R2E0F0S1) in the upper esophagus. However, biopsies showed no eosinophilia. BOS was discontinued. OVB was restarted at 0.5 mg twice daily for 2 months, then 0.5 mg once daily with deep remission. Discussion: Maintenance therapy for EoE is required. Guidance for TCS maintenance remains an unmet need including dosing, duration and frequency of TCS titration. While the BOS induction dose is 2 mg twice daily for 12 weeks, BOS maintenance dosing is unclear and currently off-label. In our patient, the switch from OVB to off-label BOS 0.5 mg maintenance dose was inadequate, resulting in recurrence. It is likely that BOS 0.5 mg (2.5 ml) is not sufficient to coat the esophagus. Furthermore, once opened, data on shelf-life stability and bioavailability of BOS are lacking. Further studies on the use of BOS at lower maintenance doses are needed.