RetGen

Each of the doses of Cand5 was found to be safe and well tolerated following repeated administration at escalating doses, Dr. Thompson said. Pharmacokinetic analysis suggested that there was no systemic exposure to Cand5 at any dose level, meaning the therapeutic effect was confined to the retina and did not migrate anywhere else in the body.

No particular safety concerns with Cand5 were identified, and the most commonly reported adverse events were related to the injection procedure. No increases in intraocular pressure were observed.

Based on these findings, Dr. Thompson said, a phase 2 trial has been approved by the FDA and is now enrolling patients.
'Gene Therapy Trials Show Promise in Treating Age-Related Macular Degeneration: Presented at AAO' (Doctor's Guide, 1 November 2005).

Saggere believes the answer lies in an approach that mimics the function of healthy photoreceptors by exploiting MEMS -- micro-electromechanical systems -- or microsystems technology. The technology enables miniature mechanical and electrical components to work as miniature machines on a chip.

His work calls for eventually implanting in a blind person's eye a chip made up of several tiny fluid-dispensing micro-pumps with droplet-size reservoirs. The reservoirs would encapsulate chemicals, called neurotransmitters, that transmit vision signals. Each micro- pump would power itself, wirelessly, by absorbing the light falling on the retina via a tiny integrated solar cell.

The pump would squirt the neurotransmitters onto the diseased retinas. The result would be a function that could substitute for natural photoreceptors lost to disease.
'Prof designing micro-pump with goal of restoring sight,' Chicago Sun-Times, 15 June 2005.

The team hopes that if the treatments are used together, treatment with oral retinoids could begin in infancy to avoid early sight loss and the difficulties associated with surgery in very young patients. And when patients are older, long-lasting drug-free treatment could be done by surgically introducing gene therapy. This study marks the first step in finding out whether these treatments will work effectively and safely in humans.
'Successful tests of new treatments in mice for eye disease causing irreversible blindness in humans' (Case Western Reserve University media release at EurekAlert, 1 November 2005).