This week, ASCRS led efforts to send a letter, in conjunction with the American Academy of Ophthalmology (AAO) and the American Society of Retina Specialists (ASRS), to the FDA. The letter included a list of bulk drug substances that should remain on the 503B Bulks List. The ASCRS FDA committee was involved in creating the list of bulk substances that are necessary for compounding certain ophthalmic drugs. The letter is in response to FDA’s draft guidance, “Evaluation of Bulk Substances Nominated for Use in Compounding Under Section 503B of the Federal Food, Drug, and Cosmetic Act,” which proposes only to include bulk drug substances on the 503B Bulks List if there is no FDA-approved drug available and there is a clinical need for the compounded drug. The ophthalmic community is concerned that this proposal may limit access to many ophthalmic compounded drugs from 503B outsourcing facilities because many FDA-approved drug products do not have the same strength, routes of administration, or formulation needed to treat ocular disease and, therefore, must be compounded from bulk substances. We encourage the FDA not to limit access to drugs produced in 503B outsourcing facilities with federal oversight that offer greater assurance of quality and included a list of bulk drug substances that should be on the 503B Bulks List. We will keep you updated.