The invention relates, in part, to compositions and methods that utilize a peptide tag that binds to hemagglutanin (HA). The HA tag can be linked to a molecule such as a protein or nucleic acid which, when administered to the eye, results in an increase in ocular half-life and/or mean residence time, and or a decrease in ocular clearance of the protein or nucleic acid. The invention also encompasses methods for treating ocular disease, including retinal vascular disease, by administering a protein or nucleic acid linked to an HA peptide tag.本發明部分地係關於利用結合至血球凝集素(HA)之肽標籤之組合物及方法。該HA標籤可連接至諸如蛋白質或核酸等分子,該蛋白質或核酸當投與眼睛時,會導致該蛋白質或核酸之眼半衰期及/或平均滯留時間延長及/或眼清除率降低。本發明亦涵蓋藉由投與連接至HA肽標籤之蛋白質或核酸來治療包括視網膜血管疾病之眼部疾病之方法。