DME drug begins Phase II dosing

Pfizer has begun dosing subjects in its Phase II trial for PF-4523655, an experimental treatment for Diabetic Macular Oedema (DME), developed in partnership with Quark Pharmaceuticals

The multicentre, prospective, randomized, dose-ranging study has enrolled 160 patients, and is evaluating the siRNA drug candidate against laser therapy in terms of safety and efficacy. Three doses of the compound will be tested and their effect on visual acuity and retinal morphology monitored over a 36-month period.

PF-4523655 is not designed to inhibit Vascular Endothelial Growth Factor (VEGF); rather, it targets RTP801, a gene that has been implicated in the abnormal development of blood vessels and leakage in the eye. In Phase I trials, the compound was shown to reduce inflammation and suppress apoptosis, and was also found to be safe and well-tolerated in subjects with wet age-related macular degeneration (AMD).

Quark believes that PF-4523655 may be suitable either as a monotherapy or as an adjunct to anti-VEGF therapy in the treatment of DME.