Comparison of visual acuity outcomes and ranibizumab treatment exposure in East-Asian and Caucasian patients with visual impairment due to myopic CNV: a RADIANCE study subgroup analysis

Abstract

 

Purpose

 

Pathologic myopia (PM) is one of the leading causes of blindness. Visual impairment due to PM is more common in East-Asians (12.2-27.4%) than Caucasians (5.8-7.8%); with approximately 10% of East-Asians and 5% of Caucasians developing myopic choroidal neovascularization (CNV). Currently it is unclear whether there is difference in treatment for myopic CNV between East-Asians and Caucasians. The RADIANCE study demonstrated that ranibizumab treatment led to rapid and sustained best-corrected visual acuity (BCVA) improvement in patients with visual impairment due to myopic CNV. We performed a post-hoc, exploratory subgroup analysis of treatment outcome and exposure comparing East-Asian and Caucasian patients of this study.

 

Methods

 

In the RADIANCE study patients (N=277) were randomized 2:2:1 to Group (G)-1 (ranibizumab treatment guided by VA stabilization), G2 (ranibizumab treatment guided by disease activity), or G3 (vPDT and as of Month [M] 3, ranibizumab and/or vPDT at investigator’s discretion). Of the randomized patients, BCVA outcomes and treatment exposure of the East-Asian (n=35) and Caucasian (n=70) patients of G2 (which was the basis for the proposed and approved label for treatment of visual impairment due to myopic CNV) were analyzed. Key outcome measures were mean change in BCVA from baseline and number of injections up to 12M.

 

Results

 

Baseline demographics and ocular characteristics of the study eye analyzed were well balanced across the subgroups (East-Asians vs Caucasians); mean age (54.2 vs 58.0 years); gender (female: 80.0% vs 75.7%), baseline BCVA (54.2 vs 55.9 letters), axial length (28.4 vs 28.9 mm), refraction sphere (10.7 vs 11.8 diopters) and lesion size (2.8 vs 2.5 mm²). At M12, the East-Asian patients gained 16.1 early treatment diabetic retinopathy study (ETDRS) letters with a median of 2.0 (mean: 2.9) injections while the Caucasian patients gained 14.1 ETDRS letters with a median of 3.0 (mean: 3.8) injections (Table).

 

Conclusions

 

East-Asian patients with myopic CNV showed numerically higher BCVA gains with one less injection than Caucasians over 12 months. Further analysis is required to explore underlying reasons and the potential predictors of BCVA outcomes and number of injections in these ethnic groups.

 

 

Mean BCVA change and number of injections up to M12

 

Keywords: 453 choroid: neovascularization • 605 myopia • 754 visual acuity