ABSTRACT
Protein drugs that neutralize vascular endothelial growth factor (VEGF), such as aflibercept or ranibizumab, rescue vision in patients with retinal vascular diseases. Nonetheless, optimal visual outcomes require intraocular injections as frequently as every month. Here we report a method to extend the intravitreal half-life of protein drugs as an alternative to either encapsulation or chemical modifications with polymers. We combine a 97-amino-acid peptide of human origin that binds hyaluronan, a major macromolecular component of the eye's vitreous, with therapeutic antibodies and proteins. When administered to rabbit and monkey eyes, the half-life of the modified proteins is increased â¼3-4-fold relative to unmodified proteins. We further show that prototype long-acting anti-VEGF drugs (LAVAs) that include this peptide attenuate VEGF-induced retinal changes in animal models of neovascular retinal disease â¼3-4-fold longer than unmodified drugs. This approach has the potential to reduce the dosing frequency associated with retinal disease treatments.
Subject(s)
Bevacizumab/administration & dosage , Ranibizumab/administration & dosage , Receptors, Vascular Endothelial Growth Factor/administration & dosage , Recombinant Fusion Proteins/administration & dosage , Retinal Diseases/drug therapy , Angiogenesis Inhibitors/administration & dosage , Angiogenesis Inhibitors/chemistry , Angiogenesis Inhibitors/pharmacokinetics , Animals , Bevacizumab/chemistry , Bevacizumab/pharmacokinetics , Disease Models, Animal , Female , Half-Life , Humans , Hyaluronic Acid/chemistry , Intravitreal Injections , Macaca fascicularis , Male , Rabbits , Ranibizumab/chemistry , Ranibizumab/pharmacokinetics , Receptors, Vascular Endothelial Growth Factor/chemistry , Recombinant Fusion Proteins/chemistry , Recombinant Fusion Proteins/pharmacokinetics , Retinal Diseases/metabolismABSTRACT
The number of therapeutic antibodies approved by regulatory agencies as novel drugs and the number of antibodies in development has increased significantly. The modular nature of antibody structure has enabled researchers to more predictably design therapeutic antibodies by choosing appropriate functional features most appropriate for a given antibody target and clinical indication. Advances in recombinant antibody technologies have allowed the routine generation of antibodies that can satisfy stringent drug design criteria, such as low immunogenicity, high affinity, target specificity, and commercially viable manufacturing methods. Engineering design opportunities exist for both the variable and the constant regions that encompass, in addition to antigen specificity and affinity, effector functions that mediate immune complex clearance or pharmacokinetics. These are discussed in the context of relevant in vivo and in vitro technologies, such as human IgG transgenic mice, phage display, and biologics manufacturing. Finally, therapeutic antibodies are compared with traditional drugs with respect to target class, selectivity, route of administration, intellectual property issues, and lead discovery and optimization.
