Regression of experimental iris neovascularization with systemic alpha-interferon.

BACKGROUND

Intraocular neovascularization leads to visual loss in many eye diseases, including diabetic retinopathy, age-related macular degeneration, and neovascular glaucoma. Current treatment relies on laser photocoagulation, involving the destruction of functional retinal tissue. A pharmacologic treatment directed at the newly growing vessels would represent a major advance.

METHODS

The authors investigated the effect of systemic alpha-interferon in an experimental model of iris neovascularization in cynomolgus monkeys. Alpha-interferon was administered systemically to animals with angiographically documented iris neovascularization.

RESULTS

Animals in the treatment group showed regression of neovascularization angiographically and histologically in eight of eight eyes. Control animals with documented iris neovascularization, followed without drug treatment, showed progression of the neovascularization in three of three eyes.

CONCLUSION

Systemic alpha-interferon led to inhibition of neovascularization and regression of new vessels in an experimental model of iris neovascularization. This represents the first successful, controlled treatment of experimental neovascularization in the eye using a systemic drug directed specifically at the neovascular tissue.