None listed
Conditions
Brief summary
The LEAD study is a multi-centre, double-blind, randomised, sham-procedure controlled, clinical trial designed to investigate the safety and efficacy of nanosecond laser microsurgical intervention as a treatment for early age-related macular degeneration. In addition, the study will provide information on visual function measures as a predictor for development of, and progression to advanced, AMD.
Interventions
The Ellex 2RT (TM) laser system is a surgical laser instrument designed for use by ophthalmologists for performing retinal procedures in order to treat conditions such as AMD.
The instrument is capable of producing a treatment beam having a short pulse of focused laser light with a wavelength of 532nm (green). These pulses can be accurately positioned on the retina of a patient's eye with the aid of a slitlamp microscope and a 635nm (red) aiming beam system. The aiming and treatment spot sizes a
The Ellex 2RT (TM) laser system is a surgical laser instrument designed for use by ophthalmologists for performing retinal procedures in order to treat conditions such as AMD. The instrument is capable of producing a treatment beam having a short pulse of focused laser light with a wavelength of 532nm (green). These pulses can be accurately positioned on the retina of a patient's eye with the aid of a slitlamp microscope and a 635nm (red) aiming beam system. The aiming and treatment spot sizes are fixed at 400 microns at the system focal plane. The coaxial aiming beam is used to position the treatment beam onto the target tissue, and a 1:1 contact lens is used for retinal treatment. The energy contained within the single short pulse is focused to the required spot size at the treatment plane so that pigmented cells can be selectively destroyed without rupturing the cell walls and without causing collateral damage to neighbouring cells or structures. The wound healing response that is then triggered is intended to improve function. The 2RT laser will be used to deliver 12 laser shots in two arcs of 6 shots superiorly and 6 shots inferiorly, inside the retinal vascular arcades at an approximate distance from the fovea of 3000 microns, with approximately one laser spot diameter between them. Laser treatment takes no more than 10 minutes but may be repeated each 6 months. The energy settings used for each of the 12 treatment single pulse laser shots will be between 0.12 mJ and 0.40 mJ, i.e., one step below the threshold energy level used to achieve blanching (or if no blanching achieved, an energy setting of 0.4mJ). Laser re-treatments may be performed at 6 monthly intervals for those participants continuing to meet none of the exclusion criteria.
Sponsors
Centre for Eye Research Australia
Study design
Allocation
Randomised controlled trial
Intervention model
Parallel
Primary purpose
Treatment
Masking
Blinded (masking used) (Subject, Investigator, Outcomes Assessor)
Eligibility
Sex/Gender
All
Age
50 Years to 95 Years
Healthy volunteers
No
Inclusion criteria
Age 50 years and older, and less than 95 years. Best Corrected Visual Acuity (BCVA) of 6/12 (20/40) or better in each eye. Bilateral high-risk early AMD (AREDS Simplified Severity Scale, at least 2 risk factors) within an inner macular zone (a circle with a radius of 1500 microns centered on the fovea). A threshold sensitivity less than 25 dB at any point, within a customised grid, as measured using a Macular Integrity Assessment (MAIA) device, at the same location of the one eye on two separate occasions. Pupil dilation of 5mm or more in each eye. Fundus photographs, OCT and FAF images of adequate quality as assessed by the LEAD Image Reading Centre. Ability and willingness to consent, and be randomised, to 2RT or sham laser treatment, and all qualification and follow-up phases of the study.
Exclusion criteria
Any imaged retinal sign suggestive of geographic atrophy within the macula (a circle with a radius of 3000 microns centred on the fovea). Peri-papillary atrophy further than 1500 microns from the fovea is allowed. CNV, or past treatment for CNV, in either eye. Any other experimental treatment for AMD, excluding dietary supplements, received in the past 12 months or thought likely to chronically change the course of the participant’s retinal disease. Any OCT image showing evidence of intraretinal fluid (cysts), or subretinal fluid for which CNV cannot be excluded as a cause. A subfoveal pigment epithelial detachment/drusenoid detachment greater than 1000 microns in diameter in either eye. Ocular disease in either eye, other than AMD, which may significantly compromise assessment of the retina, including; Known hypersensitivity to fluorescein. Previous retinal or ocular surgery, the effects of which may now or in the future complicate assessment of the progression of AMD. Requirement for any systemic or ocular medication known to be toxic to the retina. Sensitivity to the application of a contact lens. Any history of prior laser surgery to the retina. IOP of 26 mm Hg or higher, or if there is some reason to believe that the participant may have glaucoma, (e.g., history of the diagnosis of glaucoma, medical, surgical or laser intervention for the treatment of glaucoma, or disc/nerve fibre layer defects suggestive of glaucoma). Significant cataract: Nuclear cataract Grade 2 or 3, cortical cataract Grade 2 or 3 or posterior subcapsular cataract Grade 2 or 3, by Simplified Cataract Grading System (WHO Cataract Grading Group).
Outcome results
None listed