The present invention relates to hydrogel prodrug compositions comprising cross-linked hyaluronic acid (HA), or a derivative or a salt thereof, wherein the cross-linker system comprises a biodegradable spacer, wherein the cross-linked HA comprises a conjugated drug-linker, and wherein the linker is capable of releasing the drug under physiological conditions. The present invention further relates to methods for preparing the hydrogel prodrug compositions. The present invention further relates to methods for treating an ocular condition using the hydrogel compositions.本發明係關於水凝膠前藥組合物,其包含交聯化的玻尿酸(HA)或其衍生物或鹽,其中交聯劑系統包含可生物降解之間隔基,其中交聯化的HA包含結合型藥物-連接子,且其中連接子能夠在生理學條件下釋放藥物。本發明亦係關於用於製備水凝膠前藥組合物之方法。本發明亦係關於使用水凝膠組合物治療眼部病狀之方法。