Safety and Efficacy of High-Dosage Infliximab in Recalcitrant Retinal Vasculitis

Abstract

Purpose: We evaluated the long-term safety and efficacy of high-dosage infliximab and biosimilars (IFX+) in recalcitrant, non-infectious inflammatory retinal vasculitis (RV) after antimetabolite and adalimumab failure. Methods: This retrospective study included patients from the University of Illinois at Chicago Uveitis Service (2014–2024) who transitioned to IFX+ after prior treatment failure. Patients were categorized into low-dosage (LD, ≤5 mg/kg/Q4W, n = 14), medium-dosage (MD, 5.5–9.5 mg/kg/Q4W, n = 8), and high-dosage (HD, ≥10 mg/kg/Q4W, n = 9) groups. Efficacy was defined as ≥ 1 zone fluorescein angiographic (FA) improvement, prednisone reduction to < 10 mg/day with no flares, or both, at 6, 12, and 24 months, and last follow-up. Secondary outcomes included visual acuity (VA) and central macular thickness changes. Results: At 12 months, efficacy was achieved by 57.1%, 87.5%, and 88.9% of LD, MD, and HD IFX+ patients, increasing to 83.3%, 75.0%, and 100% by last visits. FA improvement rate was 60.0% (LD), 50.0% (MD), and 87.5% (HD) at 12 months, increasing to 71.4%, 60.0%, and 100% at last visits. VA significantly improved in HD by 12 months (p = 0.03) and MD by 24 months (p = 0.02). LD and MD groups required dosage increases to sustain inflammation control. By 24 months, no significant dosage differences between groups existed. No adverse events were reported in the HD group. Conclusion: In this retrospective study, medium- and high-dosage IFX+ achieved better inflammation control and visual outcomes versus low-dosage IFX+, with no additional safety concerns, in treating recalcitrant non-infectious inflammatory RV. Early initiation at greater dosages may optimize IFX response, reduce treatment duration, and improve health-related quality of life.