Cost-Effectiveness Analysis of Intravitreal Aflibercept for the Prevention of Progressive Diabetic Retinopathy
Written by: Wenlan Zhang, MD
Patel, N. Yannuzzi, N. Lin, J. Smiddy, W. A Cost-Effectiveness Analysis of Intravitreal Aflibercept for the Prevention of Progressive Diabetic Retinopathy. Ophthalmol Retina. 2022;6:213-218.
This was a cost-effectiveness analysis based on published data from two recent randomized control trials studying the early treatment of moderate/severe nonproliferative diabetic retinopathy (NPDR). Using aflibercept-treatment (IVA) data from PANORAMA and DRCR Protocol W, the authors calculated the costs required to prevent proliferative diabetic retinopathy (PDR) and center-involving diabetic macular edema (CI-DME), and the costs required to improve the diabetic retinopathy severity score (DRSS) based on 2020 Medicare reimbursement data practice settings of hospital-based facility and nonfacility. The authors calculated these values to assess the cost-utility for NPDR treatment as these studies focused on the prevention and/or reduction of disease severity, rather than measuring visual acuity outcomes. This was a different measurement as previous comparative cost-effectiveness analyses were based on an assigned utility value that was derived from visual acuity changes that were then subsequently converted to quality-adjusted life-years. Notably, costs in this study were modeled based on 2020 Medicare professional and facility fee data. The study cost model assumed 1 initial new comprehensive eye code with remaining visits billed as intermediate established eye codes. The model assumed an OCT was performed at each visit and modeled injection costs with a J code. The authors calculated costs based on the following pertinent study findings from Protocol W and PANORAMA:
DRCR Protocol W Study —
399 patients with moderate to severe NPDR (DRSS 43-53) without center-involved DME who were randomized to IVA or sham. Rate of progression to PDR at 2 years was reduced from 33.2% in the sham group to 13.5% in the IVA group. Rate of CI-DME with vision loss was reduced from 14.8% in the sham group to 4.1% in the IVA group. Improvement of 2 or more DRSS steps in 44.7% of IVA treated eyes compared to 13.7% of sham eyes.
PANORAMA Study —
402 patients with moderate to severe NPDR (DRSS 47-53) without CI-DME who were randomized to sham, 2mg IVA every 16 weeks (2Q16), and 2mg IVA every 8 weeks as needed (2Q8prn). 100-week results were analyzed. Compared to the sham group, the reported rate reduction of PDR was 9.1% in the 2Q16 group and 6.9% in the 2Q8prn group. For CI-DME, rate reduction was from 38.4% in the sham group to 11.3% in the 2Q16 group and 14.4% in the 2Q8prn group. The percentage of patients with an improvement of 2 or more DRSS steps was 13% in sham, 62% in 2Q16 group, and 50% in the 2Q8prn group.
The authors found that over 2 years in Protocol W, the cost required to prevent 1 case of PDR was $83000 ($72400) in the hospital facility (nonfacility) setting. In PANORAMA, the corresponding 2-year costs were $89400 ($75000) for the 2Q16 group, and $91200 ($89900) for the 2Q8prn group.
In Protocol W, the cost to prevent 1 case of CI-DME with vision loss was $154000 ($133000). In PANORAMA, the cost to prevent 1 case of CI-DME with or without vision loss was $70900 ($59500) for the 2Q16 group, and $90000 ($88800) for the 2Q8prn group.
The overall accumulated total for cost/DRSS unit change at the 2-year point was only calculated in Protocol W, as data for DRSS in PANORAMA was not available. This was found to be $2700 ($2400)/DRSS. This was $2100 ($1800)/DRSS in the first year and $6100 ($5300)/DRSS in the second year.
The authors conclude that there is a considerable cost associated with the prevention of PDR and CI-DME with IVA treatment of moderate/severe NPDR over 2 years, but also acquiesce that one cannot make assumptions about costs after this study period without further investigation. They suggest using the price per unit change in DRSS as a new parameter in future cost-utilization analyses.
This study (as with all cost-utilization analyses) brings up important issues to consider. The findings raise questions about whether value gained is worth the cost, and how the cost of preventing a particular complication might compare with the cost of treating a complication once it occurs (eg: PDR), both in the short-term and in the long-term. Further analyses and discussions are needed to develop metrics and benchmarks in the discussion of these kinds of treatments in the treatment of diabetic ocular disease.