The study used a commercial supplement containing lutein, zeaxanthin, vitamins C and E, and zinc. The supplement is available from Bausch and Lomb, the company that holds the patent for the AREDS supplement.
The AREDS formula, the patent for which is held by Bausch and Lomb, comprises vitamins C and E, beta carotene, zinc and copper. AREDS2 will include the antioxidant carotenoids lutein and zeaxanthin, and the omega-3 fatty acids DHA and EPA.
Professor Chakravarthy told NutraIngredients that the new supplement differed from the AREDS supplements by not containing vitamin A, while the concentrations of vitamins C and E, and zinc are different.
According to findings presented at ARVO 2009, in Florida, the combination supplement slowed down the progression of early age-related macular degeneration (AMD) to late AMD.
AMD is a degenerative retinal disease that causes central vision loss and leaves only peripheral vision, and the leading cause of legal blindness for people over 55 years of age in the Western world, according to AMD Alliance International.
Results of the Carotenoids in Age-Related Maculopathy (CARMA) study indicated that intake of high levels of lutein and zeaxanthin preserved the macular pigments. On the other hand, the macular pigments of participants in a placebo group declined steadily.
"These findings are important because this is the first randomised controlled clinical trial to document a beneficial effect through improved function and maintained macular pigments,” said the study’s coordinator, Professor Usha Chakravarthy, from Queen's Centre of Vision and Vascular Science (CVVS).
“Further research is needed to confirm these findings and to identify the numbers needed to treat to prevent 1 case from progressing from early to late AMD," she added.
According to the study protocol, published last year in Ophthalmic Epidemiology (Vol. 15, pp. 389-401), the Carotenoids in Age-Related Maculopathy (CARMA) study is a randomized, placebo-controlled, double-blind clinical trial involving 433 participants with early AMD features in at least one eye or any level of AMD in one eye with late AMD in the other eye.
“The aim of the CARMA Study is to investigate whether lutein and zeaxanthin, in combination with co-antioxidants (vitamin C, E, and zinc), has a beneficial effect on visual function and/or prevention of progression from early to late stages of disease,” state the researchers in Ophthalmic Epidemiology.
Study is ongoing, but it appears the combination of nutrients does indeed show potential against AMD.
"Late AMD causes severe sight loss and has a huge economic impact both in terms of the effects of sight loss itself and in terms of the expensive treatments that are needed to deal with the condition,” added Prof Chakravarthy.
"We wanted to carry out the study as prevention of progression to late AMD can result in a reduced financial and societal burden."
The study was funded by Dr Mann Pharma and Bausch and Lomb and sponsored by the Belfast Health and Social Care Trust.