An ocular composition can include a polymer matrix and an antibiotic dispersed in the polymer matrix. The polymer matrix can contain a thiolated hyaluronic acid moiety cross-linked to a second moiety. The composition can be configured for placement in or on an eye of a subject to provide controlled release of the antibiotic to the eye. A method of treating or preventing an ocular disease can include providing an ocular composition and applying the ocular composition to a surface of an eye of a subject to provide controlled release of the antibiotic to the eye. The ocular composition can include a polymer matrix and an antibiotic dispersed in the polymer matrix. The polymer matrix can include a thiolated hyaluronic acid moiety cross-linked to a second moiety.
