Subthreshold Nanosecond Laser Intervention in Intermediate Age-Related Macular Degeneration: Study Design and Baseline Characteristics of the Laser in Early Stages of Age-Related Macular Degeneration Study (Report Number 1)

Jia Jia Lek; Kate H Brassington; Chi D Luu; Fred K Chen; Jennifer J Arnold; Wilson J Heriot; Shane R Durkin; Usha Chakravarthy; Robyn H Guymer; Laser in Early Stages of Age-Related Macular Degeneration Study Writing Committee

doi:10.1016/j.oret.2016.12.001

Subthreshold Nanosecond Laser Intervention in Intermediate Age-Related Macular Degeneration: Study Design and Baseline Characteristics of the Laser in Early Stages of Age-Related Macular Degeneration Study (Report Number 1)

Ophthalmol Retina. 2017 May-Jun;1(3):227-239. doi: 10.1016/j.oret.2016.12.001. Epub 2017 Jan 31.

Authors

Jia Jia Lek¹, Kate H Brassington¹, Chi D Luu¹, Fred K Chen², Jennifer J Arnold³, Wilson J Heriot⁴, Shane R Durkin⁵, Usha Chakravarthy⁶, Robyn H Guymer⁷; Laser in Early Stages of Age-Related Macular Degeneration Study Writing Committee

Affiliations

¹ Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Victoria, Australia; Ophthalmology, University of Melbourne, Department of Surgery, Victoria, Australia.
² Centre for Ophthalmology and Visual Science (incorporating Lions Eye Institute), The University of Western Australia, Perth, Western Australia, Australia; Department of Ophthalmology, Royal Perth Hospital, Perth, Western Australia, Australia.
³ Marsden Eye Research, Sydney, Australia.
⁴ Heriot Eyecare, Victoria, Australia.
⁵ Adelaide Eye and Retinal Centre, Adelaide, Australia.
⁶ Belfast Health and Social Care Trust, Belfast, Northern Ireland.
⁷ Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Victoria, Australia; Ophthalmology, University of Melbourne, Department of Surgery, Victoria, Australia. Electronic address: rhg@unimelb.edu.au.

PMID: 31047426
DOI: 10.1016/j.oret.2016.12.001

Abstract

Purpose: The Laser Intervention in Early Stages of Age-Related Macular Degeneration (LEAD) study is an investigation of the safety and efficacy of subthreshold nanosecond laser treatment to slow the progression of intermediate age-related macular degeneration (AMD). This report presents the novel study design and baseline characteristics.

Design: Multicenter, double-masked, randomized controlled, medical device feasibility clinical trial.

Participants: Persons with bilateral drusen >125 μm within 1500 μm of the fovea, monocular best-corrected visual acuity (BCVA) ≥20/40, and microperimetric retinal sensitivity of <25 decibels (dB) in at least 1 location within central 6° in 1 eye. Signs of late AMD; choroidal neovascularization or geographic atrophy, or anatomic end points defined on multimodal imaging (MMI) as fundus autofluorescence-defined atrophy, spectral-domain OCT (SD-OCT)-defined atrophy, or nascent GA excluded participation.

Methods: Participants were randomized to nanosecond or sham laser treatment. Twelve laser or sham spots are applied to the macular region of the study eye. Participants are reviewed in visits every 6 months with functional testing and MMI for 36 months and are re-treated at each visit (until 30 months) if an end point is not reached in the study eye.

Main outcome measures: Progression to late AMD or MMI-defined anatomic end points in the study eye.

Results: A total of 292 participants across 6 centers were enrolled, with 145 participants randomized to arm 1 and 147 participants randomized to arm 2. Population characteristics at baseline were as follows: median age 70 years, 73% female, 90% Anglo-Saxon, and 3% current smokers. Baseline ocular characteristics of the study eyes were BCVA of 83 letters (20/25); low luminance visual acuity (LLVA) of 68 letters (20/50); hyperpigmentation, 33%; reticular pseudodrusen, 23%; square root drusen area (SD-OCT), 0.77 mm; square root drusen area (color photographs), 0.92 mm; cube root drusen volume (SD-OCT), 0.26 mm; average retinal sensitivity, 26 dB; and worst point retinal sensitivity, 20 dB. Only lutein supplement use was significantly different between treatment arms.

Conclusions: The LEAD study uses novel inclusion/exclusion criteria and end points in an attempt to optimize our study design. Risk characteristics for progression to study end points are equally distributed between treatment arms.