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Intravitreal Anti-VEGF Injection Transitions Across Bevacizumab, Biosimilar, and Branded Medications: The IRIS
Sean T Berkowitz1, Joshua B Gilbert2, Connor J Ross2
1Department of Ophthalmology, Vanderbilt University Medical Center, Nashville, TN, USA.
Journal of Vitreoretinal Diseases
|June 23, 2026
Summary
Medication transitions in neovascular age-related macular degeneration (nAMD) may cause care delays. Multiple transitions, especially involving biosimilars and branded agents, are more costly than direct switches from bevacizumab.
Area of Science:
- Ophthalmology
- Pharmacoeconomics
- Retinal Diseases
Background:
- Neovascular age-related macular degeneration (nAMD) requires ongoing treatment with antivascular endothelial growth factor (anti-VEGF) medications.
- Medication transitions are common in nAMD management, but their impact on care delays and costs is not fully understood.
Purpose of the Study:
- To characterize anti-VEGF medication transitions in nAMD patients.
- To evaluate associated delays in care and economic impacts.
- To compare different transition pathways from bevacizumab.
Main Methods:
- Retrospective observational cohort study using the IRIS Registry (2015-2024).
- Analysis of four cohorts based on anti-VEGF medication sequences: bevacizumab only, bevacizumab to biosimilar, bevacizumab to branded, and bevacizumab to biosimilar then branded.
- Outcome measures included intravitreal injection events, medication transitions, and injection intervals.
Main Results:
- Over 182,000 eyes with nAMD were analyzed.
- Newer agents (faricimab, aflibercept 8 mg) showed an 8.6-day delay compared to aflibercept 2 mg.
- Economic modeling indicated that transitioning from bevacizumab to a biosimilar then a branded agent was significantly more costly over 2, 5, and 10 years compared to direct transitions.
Conclusions:
- IRIS Registry data suggest demographic variations in patients undergoing medication transitions, including biosimilars.
- Medication transitions in nAMD can lead to delays in care.
- Multiple medication transitions appear more costly than direct transitions from bevacizumab to either biosimilar or branded agents.
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