Effect of derivatization of the bioavailability of ophthalmic steroids. Development of an in vitro method of evaluation.

An in vitro method for evaluating efficacy of ophthalmic steroid preparations was developed using bovine eyes. The method was tested using three derivatives of dexamethasone (alcohol, acetate, and sodium phosphate) and the results obtained were similar to those obtained in studies using live rabbits, although differences were noted. Bioavailability of the acetate was greatest; that of the sodium phosphate was the lowest. On the basis of this study, bovine eyes could be used as an alternative method for assessing ophthalmic steroid efficacy.