title: Highly potent VEGF-A-antagonistic DARPins as anti-angiogenic agents for topical and intravitreal applications.
abstract: The next-generation ophthalmic anti-VEGF therapeutics must aim at being superior to the currently available agents with regard to potency and improved drug delivery, while still being stable and safe to use at elevated concentrations. We show here the generation of a set of highly potent VEGF-A antagonistic DARPins (designed ankyrin repeat proteins) delivering these properties. DARPins with single-digit picomolar affinity to human VEGF-A were generated using ribosome display selections. Specific and potent human VEGF-A binding was confirmed by ELISA and endothelial cell sprouting assays. Cross-reactivity with VEGF-A of several species was confirmed by ELISA. Intravitreally injected DARPin penetrated into the retina and reduced fluorescein extravasation in a rabbit model of vascular leakage. In addition, topical DARPin application was found to diminish corneal neovascularization in a rabbit suture model, and to suppress laser-induced neovascularization in a rat model. Even at elevated doses, DARPins were safe to use. The fact that several DARPins are highly active in various assays illustrates the favorable class behavior of the selected binders. Anti-VEGF-A DARPins thus represent a novel class of highly potent and specific drug candidates for the treatment of neovascular eye diseases in both the posterior and the anterior eye chamber.
authors.affiliation: Universitäts-Augenklinik Freiburg, Freiburg, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Stahl
authors.forename: Michael T
authors.initials: MT
authors.lastname: Stumpp
authors.forename: Anja
authors.initials: A
authors.lastname: Schlegel
authors.forename: Savira
authors.initials: S
authors.lastname: Ekawardhani
authors.forename: Christina
authors.initials: C
authors.lastname: Lehrling
authors.forename: Gottfried
authors.initials: G
authors.lastname: Martin
authors.forename: Maya
authors.initials: M
authors.lastname: Gulotti-Georgieva
authors.forename: Denis
authors.initials: D
authors.lastname: Villemagne
authors.forename: Patrik
authors.initials: P
authors.lastname: Forrer
authors.forename: Hansjürgen T
authors.initials: HT
authors.lastname: Agostini
authors.forename: H Kaspar
authors.initials: HK
authors.lastname: Binz
mesh_terms: D000287:Administration, Topical; D020533:Angiogenesis Inhibitors / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D000818:Animals; D017089:Ankyrin Repeat; D001808:Blood Vessels / Q000187:drug effects / Q000254:growth & development; D020256:Choroidal Neovascularization / Q000188:drug therapy / Q000473:pathology; D004195:Disease Models, Animal; D004353:Drug Evaluation, Preclinical; D005123:Eye / Q000098:blood supply / Q000187:drug effects / Q000473:pathology; D061307:Human Umbilical Vein Endothelial Cells / Q000187:drug effects / Q000378:metabolism; D006801:Humans; D058449:Intravitreal Injections; D051379:Mice; D009883:Ophthalmic Solutions / Q000494:pharmacology / Q000627:therapeutic use; D011485:Protein Binding / Q000187:drug effects; D011817:Rabbits; D051381:Rats; D011914:Rats, Inbred BN; D011994:Recombinant Proteins / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D042461:Vascular Endothelial Growth Factor A / Q000037:antagonists & inhibitors* / Q000378:metabolism
chemical_list: D020533:Angiogenesis Inhibitors; D009883:Ophthalmic Solutions; D011994:Recombinant Proteins; D042461:Vascular Endothelial Growth Factor A