CFR›Title 21›Chapter I›Part 316›Subpart E ContainsSection 316.40CorpusDaily eCFRDisplayed edition2026-04-15Last updated2026-04-15 Subpart E—Open Protocols for Investigations Sections 316.40 § 316.40 Treatment use of a designated orphan drug. Previous D Subpart D—Orphan-drug Exclusive Approval Next F Subpart F—Availability of Information