A commentary on testing rapamycin as a therapy for age-related macular degeneration (AMD): "Although neovascular AMD only accounts for less than 15% of the overall age-related macular degeneration, it is responsible for over 80 percent of the severe vision loss cases. ... It was reported in 2004 that rapamycin (trade name sirolimus) treatment significantly reduced the extent of neovascularization [induced] in adult mice ... In an advance online publication this year [Kolosova et al] presented exciting results that rapamycin could actually prevent AMD-like retinopathy in an aging rat model that more closely resembles human AMD pathology. They investigated the effect of rapamycin on spontaneous retinopathy in senescence- accelerated OXYS rats. OXYS rats were treated orally with either 0.1 or 0.5 mg/kg rapamycin, which was given together with food. Rapamycin was found in a dose-dependent manner to reduce the incidence and severity of retinopathy, and attenuated AMD disease progression. Some histological abnormalities associated with retinopathy were notably reduced ... significantly, rapamycin prevented destruction of ganglionar neurons in the retina. Rapamycin did not exert any adverse effects on the retina in control disease-free Wistar rats, suggesting that it is safe."