Date of Award
2025
Degree Type
Thesis
Degree Name
Master of Science in Pharmaceutical Sciences
Specialization
Health Outcomes
Department
Biomedical and Pharmaceutical Sciences
First Advisor
Stephen Kogut
Abstract
Statement of the Problem: Age-related macular degeneration (AMD) and diabetic retinopathy (DR) are leading causes of blindness and low vision in the United States. In 2019, approximately 19.8 million Americans were living with AMD, which is classified into dry (non-neovascular) and wet (neovascular) forms, with the latter being more severe. DR, a complication of diabetes, affected an estimated 9.6 million Americans in 2021, with progression leading to proliferative DR (PDR) and diabetic macular edema (DME), both of which can cause vision loss. Vascular endothelial growth factor (VEGF) inhibitors are the standard treatment for these retinal diseases, targeting abnormal angiogenesis and vascular permeability. Given the high costs associated with these therapies, particularly ranibizumab and aflibercept, increasing biosimilar utilization has the potential to reduce healthcare spending.
Methods: This study analyzes national and Rhode Island-specific utilization trends of VEGF inhibitors using Medicare Part B and Rhode Island All-Payer Claims Database (RI APCD) data. Three aims are pursued: (1) determining trends in VEGF-inhibitor utilization in Medicare Part B from 2018-2022, (2) estimating potential cost savings to Medicare through a budget impact model considering various rates of biosimilar uptake, and (3) comparing Rhode Island utilization patterns with national trends, and examining RI utilization by patient demographics, insurance type, age-group, and eye disease type. Cross-sectional analyses and logistic regression models assessed associations between independent variables and VEGF-inhibitor use.
Results: VEGF inhibitors constitute a significant expenditure in Medicare Part B nationally, exceeding $4.5 billion in 2022. The budget impact analysis estimated that increased uptake of biosimilars, priced at 65% of brand drug costs, could generate substantial annual cost savings in the range of $455 million to $1.06 billion with aflibercept and ranibizumab.
Chi-square analyses of Rhode Island utilization data revealed significant associations between at least one VEGF-inhibitor utilization and younger patients (18-64), insurance type (commercial), and residing in a low-income zip code (all with p < 0.0001), and DME/DR disease type (p = 0.0225). Older patients and those diagnosed with AMD were less likely to receive a VEGF inhibitor than compared to younger patients and those with DME/DR. However, no statistically significant association was found between VEGF-inhibitor use and gender (p = 0.3135). These findings highlight differences in VEGF-inhibitor utilization across demographic factors, insurance coverage, and disease type, which may inform policy decisions to optimize prescribing and improve accessibility.
Conclusion: This study underscores the economic impact of VEGF inhibitors and the potential cost-saving potential of biosimilars. By identifying utilization trends and assessing potential biosimilar adoption, the findings can inform policy recommendations aimed at reducing the financial burden on Medicare and improving access to effective treatments for retinal diseases.
Recommended Citation
Izzio, Kevin, "ANALYSIS OF THE UTILIZATION OF VEGFINHIBITORS IN RHODE ISLAND AND IN MEDICARE PART B NATIONALLY" (2025). Open Access Master's Theses. Paper 2609.
https://digitalcommons.uri.edu/theses/2609