Abstract
Purpose :
The main outcome results of the SCORE2 trial demonstrated that, among patients with macular edema due to central (CRVO) or hemi-retinal vein occlusion (HRVO), intravitreal bevacizumab was non-inferior to aflibercept with respect to visual acuity after 6 months of monthly injections. The current study evaluates the cost-effectiveness of treatment initiation with bevacizumab versus aflibercept.
Methods :
We modeled two algorithms: 1) initiate bevacizumab, switching to aflibercept if a patient does not respond to treatment; 2) initiate treatment with aflibercept,. A microsimulation model was constructed simulating 10,000 participants in TreeAge Pro using SCORE 2 data. Parameter estimates were drawn from an a priori distribution creating 100 independent simulations to be pooled. Cost of treatment with bevacizumab and aflibercept was taken from the literature. Patient-centered effectiveness was measured using quality adjusted life years (QALYs) estimated in a two-stage process. First, baseline utility scores were estimated for all participants from NEI-VFQ scores applying a mapping algorithm by Payakachat. Next, utility scores were mapped to visual acuity and other factors using a mixed model method (SAS PROC MIXED). ETDRS best-corrected visual acuity (BCVA) in the best-seeing eye and asymmetry in ETDRS BCVA between eyes had the best fit. The incremental cost-effectiveness ratio for the simulation is reported.
Results :
In the simulation, participants initiated with aflibercept gained 1.7 more letters in the treated eye at 6 months than patients initiated with bevacizumab and 3.9 more letters at 12 months. Approximately 20% of simulants who initiated treatment on bevacizumab switched to aflibercept within six months. The difference in QALYs (a person-based measure) was 0.001 QALY favoring those initiated with bevacizumab due to modest differences in the untreated eye. Treatment of those initiated with aflibercept was $20,029 more after 12 months than those initiated with bevacizumab.
Conclusions :
Initiating treatment with bevacizumab in patients with CRVO- or HRVO-associated macular edema, and reserving treatment with aflibercept for those who do not respond to initial treatment, is likely to be a preferred strategy from the perspective of payors considering benefits in the broader health sector.
This is a 2021 ARVO Annual Meeting abstract.