
A world-first ‘nanosecond laser study’ has shown promising results in slowing the progression to vision loss, of the most common cause of severe vison loss in the Western world, age-related macular degeneration (AMD).
Principal Investigator Professor Robyn Guymer AM from the Centre for Eye Research Australia (CERA) announced the results of the three-year multi-centred, randomised, controlled trial today at the International Euretina Meeting in Vienna, Austria.
nanosecond laser treatment, delivered to one eye… showed a promising trend towards reducing the overall rate of disease progression in the treated eye of participants with large drusen
Nearly 300 patients from sites across Australia and Northern Ireland, received six monthly treatments as part of this study.
Prof. Guymer reported that the nanosecond laser treatment, delivered to one eye, using an Australian designed and manufactured laser called the Retinal Rejuvenation Therapy (2RT) Laser: (Ellex Medical Lasers Limited, Adelaide), showed a promising trend towards reducing the overall rate of disease progression in the treated eye of participants with large drusen (lipid rich deposits) which characterise the earlier stages of the disease, when people still have excellent vision but are at risk of progressing to vision loss.
This main outcome was not statistically significant, however, different clinical groups appeared to respond differently to the treatment. Patients with less severe signs of AMD (representing 76 per cent of the participants) showed nearly a four-fold decrease in progression rate of their disease, whereas participants with more severe signs of disease at the beginning of the trial (24 per cent of participants) had a doubling of their progression rate to late stages of AMD when compared to participants who were not treated.
Prof. Guymer said, “Whilst this new laser isn’t a cure, and it is not suitable for every person with early stages of AMD, this is an important outcome in reducing progression to late disease. If validated in future trials, this will be the first time that a laser intervention has successfully addressed AMD disease progression from its early stages to late AMD in more than 20 years of AMD laser research.”
Prof. Guymer now wants to conduct further studies to validate these initial results. These interesting and promising results of a significant treatment effect, modified by the type of AMD present, are important to explore further. The potential for benefit, representing the first demonstrated specific intervention to slow AMD progression, as well as potential for harm in a specific, more severe clinical group, with nanosecond laser treatment, requires validation through a confirmatory study.
“The findings of this study gives us reason to be optimistic, but at the same time, also highlight the need to better understand the patient selection requirements for 2RT. It is important to note that 2RT cannot be used in all patients with the earlier stages of AMD,” said Prof. Guymer.
“The laser technique and protocol used, as well as the careful selection of participants based upon the clinical classification of AMD, will be a critical consideration,” she said.
“Being able to replicate the results quickly is important in order to confirm the benefit and safety profile of 2RT, as demonstrated to date.”
Prof. Guymer says that it is not possible to extrapolate these results achieved with the 2RT laser to other subthreshold lasers which are currently available as their mode of action is not the same as that of the 2RT nanosecond laser.
Prof. Guymer further commented that the LEAD trial is the first trial in AMD to base the disease stage upon signs seen only on the high-resolution imaging rather than having to rely upon what a clinician can see and this ability provides the opportunity to intervene much earlier in the disease as changes in these very early signs of disease can now be detected and monitored. Until now, interventions have had to start once there is already death of cells and loss of part of the vision.