Longitudinal Sub-Retinal Pigment Epithelium Disease Burden Assessment in Neovascular Age-Related Macular Degeneration: Results from the OSPREY Study

Abstract

Purpose : Disease burden in the sub-retinal pigment epithelium (sub-RPE) compartment (e.g., pigment epithelial detachments, choroidal neovascular tissue, drusen) is still challenging area of assessment for treatment response and disease outcomes. This analysis utilizes volumetric assessment of the sub-RPE compartment through multi-layer segmentation assessment to evaluate the longitudinal response of the sub-RPE disease burden in nAMD treated with brolucizumab or aflibercept in the OSPREY trial.

Methods : The OSPREY trial is a phase 2, randomized, double-masked, active-controlled, 56-week study comparing brolucizumab 6 mg and aflibercept 2 mg in nAMD. After the initial loading phase, both groups received q8w dosing until Week 40, after which the brolucizumab group was extended to q12w dosing until Week 56, while the aflibercept group was maintained on q8w dosing. SD-OCT scans for each timepoint were uploaded to a novel software platform for multi-layer volumetric assessment. Total sub-RPE volume (mm³), which is defined as the total volume between the RPE and Bruch’s membrane across the macular cube, was quantified. Statistical analyses were conducted for hypothesis generation without adjustment for multiple comparisons.

Results : At baseline, the total sub-RPE volumetric disease burden was 0.92mm³ and 0.79mm³ for the brolucizumab and aflibercept groups, respectively. Following treatment, the sub-RPE disease burden volume decreased significantly for both groups (P<0.05 vs baseline, at each timepoint for each group). Brolucizumab and aflibercept subjects demonstrated mean volume changes of -0.17mm³ and -0.10mm³ at Week 4, -0.20mm³ and -0.11mm³ at Week 40, and -0.20mm³ and -0.12mm³ at Week 56, respectively. Mean percentage changes in volume were -11.83% and -7.90% at Week 4, -14.12% and -7.63% at Week 40, and -14.49% and -8.26% at Week 56 for brolucizumab and aflibercept patients, respectively.

Conclusions : This analysis provides a unique assessment of the sub-RPE compartment. This assessment demonstrates significant reduction in sub-RPE disease burden following brolucizumab and aflibercept treatment. This reduction continues in the brolucizumab group following interval extension to 12 weeks.

This is a 2020 ARVO Annual Meeting abstract.