Association of Baseline Characteristics and Early Vision Response with 2-Year Vision Outcomes in the Comparison of AMD Treatments Trials (CATT)

Abstract

Purpose: To evaluate the association of baseline characteristics and early visual acuity (VA) response with visual outcomes at years 1 or 2 in the Comparison of Age-Related Macular Degeneration (AMD) Treatments Trials (CATT).

Design: Secondary analysis of CATT.

Participants: The 1185 CATT participants with baseline VA of 20/25 to 20/320.

Methods: Participants were assigned to ranibizumab or bevacizumab and to 1 of 3 dosing regimens. Associations of baseline characteristics and early VA response (week 4 or 12) with VA response at years 1 or 2 were assessed by R(2) from linear regression analyses. Patients who had a poor initial response (VA 20/40 or worse with persistent fluid and without ≥1-line VA gain) were defined as candidates for changing treatment.

Main outcome measures: Visual acuity change from baseline.

Results: Statistically significant (P < 0.05) baseline predictors for less VA gain at year 2 were older age, VA of 20/40 or better, larger choroidal neovascularization area, presence of geographic atrophy, total foveal thickness ≤325 μm or ≥425 μm, and elevation of retinal pigment epithelium. Among 176 eyes gaining ≥3 lines at week 12, 78% had a ≥3-line gain at year 2, whereas among 113 eyes losing ≥1 line at week 12, 27% improved to a ≥1-line gain at year 2. Visual acuity response at week 12 was more predictive of VA response at year 2 (R(2) = 0.30) than VA response at week 4 (R(2) = 0.17) and baseline predictors (R(2) = 0.13; P < 0.0001). Among 126 candidates for changing treatment drug at week 12, mean VA improved by 2.8 letters (P = 0.050), mean total retinal thickness decreased 53 μm (P < 0.0001), and fluid resolved in 33% (P < 0.0001) between week 12 and year 1 with continued use of the same drug and regimen. Similar improvements were observed among 83 candidates for changing drugs at week 24.

Conclusions: Visual acuity response at week 12 is more predictive of 2-year vision outcomes than either several baseline characteristics or week 4 response. Eyes with poor initial response may benefit from continued treatment without switching to another drug.

Figure 1. The VA response category (≥1 line gain, <1 line change, ≥1 line loss) at Year 1 or at Year 2 by the early VA response category at week 4 or at week 12

(A) VA response category at Year 1 by VA response at Week 4; (B) VA response category at Year 1 by VA response at Week 12; (C) VA response category at Year 2 by VA response at Week 4; (D) VA response category at Year 2 by VA response at Week 12.

Figure 1. The VA response category (≥1 line gain, <1 line change, ≥1 line loss) at Year 1 or at Year 2 by the early VA response category at week 4 or at week 12

(A) VA response category at Year 1 by VA response at Week 4; (B) VA response category at Year 1 by VA response at Week 12; (C) VA response category at Year 2 by VA response at Week 4; (D) VA response category at Year 2 by VA response at Week 12.

Figure 1. The VA response category (≥1 line gain, <1 line change, ≥1 line loss) at Year 1 or at Year 2 by the early VA response category at week 4 or at week 12

(A) VA response category at Year 1 by VA response at Week 4; (B) VA response category at Year 1 by VA response at Week 12; (C) VA response category at Year 2 by VA response at Week 4; (D) VA response category at Year 2 by VA response at Week 12.

Figure 1. The VA response category (≥1 line gain, <1 line change, ≥1 line loss) at Year 1 or at Year 2 by the early VA response category at week 4 or at week 12

(A) VA response category at Year 1 by VA response at Week 4; (B) VA response category at Year 1 by VA response at Week 12; (C) VA response category at Year 2 by VA response at Week 4; (D) VA response category at Year 2 by VA response at Week 12.