Long-term anti-angiogenic activity of intravitreal ellipsoid particles for NVAMD Niranjan B. Pandey, Ph.D. - PI Aleksander S. Popel, Ph.D. - Co-I Jordan J. Green Ph.D. - Co-I Peter A. Campochiaro M.D. - Co-I of subaward Project Summary: Current therapies for wet age-related macular degeneration (AMD) target vascular endothelial growth factors (VEGFA, and placental growth factor PlGF). These include Ranibizumab and Aflibercept. Ranibizumab targets all forms of VEGFA while aflibercept also targets both forms of PlGF. However these drugs do not improve visual acuity in 60-65% of AMD patients, suggesting that other non-VEGF/PlGF pathways are active in these patients. Ranibizumab is administered intravitreally monthly while aflibercept is administered bimonthly after 3 months of monthly injections. Monthly injections increase the risk of infections and are burdensome to patients. Recently, patients have shown their desire to switch to fewer injections by the rapid pace with which aflibercept is making inroads into the AMD market compared to ranibizumab. Finally ranibizumab and aflibercept, although effective, do not cause regression of existing neovasculature, only inhibition of the growth of new vasculature, thus limiting their efficacy. Thus, there is an unmet medical need to target patients that do not respond to current therapies, to extend the time between intravitreal administrations even more to achieve cost savings and reduce side effects, and for agents that can reverse the symptoms of the disease in patients. We propose to develop a peptide therapeutic that could fulfill this medical need. We have developed an innovative prolate ellipsoid microrparticle (microtorpedo) that can encapsulate a wide variety of payloads and is expected to be long-lived in the eye because of its particular polymeric design and its phagocytosis-resistant shape. The anti-angiogenic peptide can block angiogenesis in the presence of VEGF and non-VEGF growth factors. Here we propose to combine these two technologies to design and fabricate a microtorpedo packaged with our lead anti-angiogenic biomimetic peptide derived from the ?5 fibril of collagen IV. We present data showing potent efficacy of the peptide in 2 widely used mouse models of AMD and data showing that a close analog of the peptide causes regression of the neovasculature and shows promising inhibition of retinal detachment. Our therapeutic microtorpedo which has been designed for a long half-life in vivo will solve all 3 problems we set out to solve: they will relese peptide over a period of 6 months thus reducing the frequency of intravitreal injections from 12 times a year to 2 times a year, the released peptide will inhibit multiple angiogenic signaling pathways simultaneously because of its mechanism of action, and the peptide will also cause regression of the existing neovasculature thus potentially reversing symptoms of the disease. Any new drug introduced into this space should perform better than aflibercept in head-to-head in vivo models to be commercially viable;thus we propose to test our therapeutic compared to aflibercept in all of our in vivo studies.
This project will design and evaluate new biodegradable ellipsoid microparticles encapsulating an anti-angiogenic peptide for the treatment of neovascular (wet) age-related macular degeneration (NVAMD). This peptide is effective for inhibiting NVAMD in the mouse, causing regression of neovasculature, and inhibiting neovascular permeability. The novel ellipsoid shape of the particles will allow them to persist and release the active therapeutic over many months.
|Silva, Raquel Lima E; Kanan, Yogita; Mirando, Adam C et al. (2017) Tyrosine kinase blocking collagen IV-derived peptide suppresses ocular neovascularization and vascular leakage. Sci Transl Med 9:|