Gene-therapy approach appears to work for AMD drug

Scientists at Tufts University have found a promising gene-therapy approach to treating age-related macular degeneration (AMD), the most common cause of blindness among the elderly. The researchers used a protein called CD59 and delivered it via a gene-therapy approach, resulting in significantly reduced uncontrolled blood vessel growth and cell death. The study was published in the open-access journal PLoS ONE. And, according to Mass High Tech, the study has led to a partnership between Tufts and a Boston startup, Hemera Biosciences, to take the therapy toward Phase I trials.

Here's how it works: CD59 blocks the formation of "membrane attack complex" (MAC) in cell membranes, which are holes or pores in the back of the eye that lead to AMD. "CD59 is unstable and hence previous studies using CD59 have had limited success," said senior author Rajendra Kumar-Singh in a release. "The gene therapy approach that we developed continuously produces CD59 in the eye and overcomes these barriers, giving us renewed hope that it can be used to fight the progression of AMD and potentially other diseases."

Kumar-Singh and colleagues used a deactivated virus similar to one previously shown to be safe in humans. Using mouse models of AMD, the researchers found that eyes treated with CD59 had 62 percent less uncontrolled blood vessel growth and 52 percent less MAC than controls.

"Treatment was effective when administered at a very specific location beneath the retina, but importantly, also when it was administered to the center of the eye," said Siobhan Cashman in a release. "This finding is especially encouraging because it would allow for a safer and more convenient route of administration of treatment."

Mass High Tech reports that Hemera is seeking venture capital funding to take the technology to trials.

- read the release from Tufts
- and the story in Mass High Tech
- the study can be found in PLoS ONE