Provided is a method of identifying Hsp90 inhibitors with substantially less ocular toxicity or with substantially improved ocular toxicity profile. The method comprises measuring the respective concentrations of an Hsp90 inhibitor in the retina and plasma at certain time points following the administration of the Hsp90 inhibitor in a subject, and determining the concentration ratio of the Hsp90 inhibitor between retina and plasma, where a certain ratio is indicative that the Hsp90 inhibitor has substantially less ocular toxicity. The method also includes identifying an Hsp90 inhibitor with substantially less ocular toxicity, or with a substantially improved ocular toxicity profile, by determining the elimination rate of the Hsp90 inhibitor from the retina following administration of the Hsp90 inhibitor, where a certain elimination rate is indicative that the Hsp90 inhibitor will induce substantially less ocular toxicity.
