Delivery systems for the treatment of proliferative vitreoretinopathy: materials, devices and colloidal carriers

Proliferative vitreoretinopathy (PVR), the most serious complication causing retinal detachment surgery to fail, is one of the leading causes of vision-loss in developed countries. The pharmaceutical treatment of this disease, located in the posterior segment of the eye, is problematic because it is difficult to achieve effective drug levels in the vitreous and the retina through conventional forms of administration (topical or systemic). Intravitreal injections can deliver drugs to the retina without the side-effects associated with systemic administration. However, because PVR is a long-term complication and the half-life of most drugs in the vitreous cavity is short, repeated injections are needed but this can cause complications. Recent advances in ocular drug delivery methods and the development of novel bioactive compounds could lead to new ways for the treatment of PVR. This review will summarize recent literature concerning intraocular drug delivery of biopharmaceutical agents for the treatment and prevention of PVR.