BACKGROUND AND AIMS: We investigated the long-term safety and efficacy of budesonide oral suspension (BOS) in eosinophilic esophagitis (EoE). METHODS: This study (SHP621-303) was a 4-year, phase 3, open-label study in patients with EoE who completed up to 52 weeks of BOS therapy in two preceding phase 3 studies. Based on treatment assignments in previous studies, patients were assigned to BOS-BOS or placebo-BOS groups. All patients received BOS 2.0 mg twice daily
dose reductions to once daily and interruptions were permitted. The safety and tolerability of BOS was primarily investigated, with exploratory efficacy endpoints also examined. RESULTS: Overall, 131 patients were included. BOS was well tolerated, with no unexpected safety signals observed. Treatment-emergent adverse events (TEAEs) occurred in 76.3% of patients
most were mild/moderate in severity and unrelated to study drug. The most frequently reported BOS-related TEAEs included abnormal adrenocorticotropic hormone stimulation test results (8.4% [11/131]
number of events [m] = 12) and adrenal insufficiency (2.3% [3/131]
m = 3). Esophageal candidiasis occurred in 3.1% of patients ([4/131]). The aforementioned TEAEs resolved in most patients. At month 48 of treatment, 50.0% and 58.3% of patients achieved/maintained a histologic response (≤6 and <
15 eosinophils per high-power field, respectively). The initial reduction (-3.6) in total EoE Endoscopic Reference Score from baseline to the first visit was maintained until month 48. CONCLUSION: Long-term treatment with BOS was well tolerated. Despite dosing changes/interruptions, approximately half of patients achieved/maintained a histologic response
initial improvements in endoscopic outcomes were maintained over 48 months.