Skyran Biologics, Inc.
Skyran Biologics is developing a small protein therapeutic, delivered as an eye drop, a mimetic of the active binding region of Pigment Epithelium-Derived Factor (PEDF), to treat diabetic retinopathy (DR), a leading cause of blindness.
Skyran’s preclinical data show that an eye drop formulation of this molecule delivers the active ingredient to the retina and can significantly reduce or halt retinal degeneration, thereby reducing or eliminating loss of sight caused by diabetic retinopathy.
PEDF is a 418-amino acid polypeptide in the serpin gene family secreted by the retinal cells.
The protein is widely recognized for its neuroprotective, anti-inflammatory, and anti-angiogenesis activities in the retina and other tissues and may be deficient in diabetic patients. Skyran has isolated a 17-mer minimum active region of PEDF and used a series of conservative peptide modification strategies to obtain several novel, more active PEDF mimetics.
Spx81-5, the lead PEDF mimetic, has increased biological activity over the native fragment.
Spx81-5 shows no evidence of toxicity in preliminary studies, and adopts a well-defined alpha helical structure making it a pharmaceutically attractive molecule. Skyran has formulated Spx81-5 for topical use as an eye drop that shows bioavailability in the Ins2Akita genetic mouse model of DR and in the non-human primate eye. Spx81-5 and several analogs are protected by U.S. patent 9,611,314, filed September 12, 2014 and issued April 4, 2017.
Spx81-5 Is Active When Delivered By Eye Drop
Immunolabeling studies show that Spx81-5 achieves widespread deposition in the mouse retinal. Additional studies demonstrate that Spx81-5 administered as an eye drop reaches significant levels in the monkey vitreous.