A glimpse of hope was offered to blind people this week after U.S. clinical trials showed transplanted stem cells improved the sight of two patients with severe vision problems.
The research, which is touted as the first use of embryonic stem cells being transplanted into a human patient, examined legally blind patients who were in advanced stages of two progressive diseases. A 78-year-old woman had dry age-related macular degeneration, which is the leading cause of blindness in the developed world, while another -- a 51-year-old woman -- suffered from Stargardt's macular dystrophy, which is the most common cause of juvenile blindness.
In the latter case, the patient, who was unable to identify a single letter on a visual chart was able to see five letters after receiving the treatment. For the patient with dry age-related macular degeneration, that number improved from 21 letters to 28.
"This is the first published report of embryonic stem cells in humans for any purpose whatsoever," said study lead Dr. Robert Lanza, chief scientific officer from Advanced Cell Technology in Massachusetts, which funded the trials.
"These patients are quite advanced in their disease and there's currently no treatment at all for either of these (patients). Ultimately, what we want to really do is not to cure blindness, but rather to slow down or prevent the onset of the disease process."
The study, published this week in the medical journal The Lancet, reported the retinal cells (RPE) that were replaced using stem cells show resilience and could open the possibility to future improvement in treating blind patients.
"The (stem cells) showed no signs of apparent rejection after four months," read the study. "The future therapeutic goal will be to treat patients earlier in the disease process, potentially increasing the likelihood of photoreceptor and central visual rescue."
The study noted, however, researchers were "uncertain at this point whether any of the visual gains we have recorded were due to the transplanted cells, the use of immunosuppressive drugs or a placebo effect."
Lanza said the improvements in quality of life for the two patients in the study were astounding, despite the advanced stage of their conditions. He said in the case of the 78-year-old patient, she went from only being able to detect hand movements, to counting fingers and threading needles in a matter of a week or so.
"If we can show these (treatments) are safe and well tolerated, we can start treating patients earlier, where more significant findings would potentially be expected," he said.
-- Postmedia News