Unballoted STU Update of HL7 FHIR® Implementation Guide: DaVinci Payer Data Exchange US Drug Formulary, Release 1 STU2.1 – US Realm
Learn more at https://www.hl7.org/implement/standards/product_brief.cfm?product_id=517 or see the specification at http://hl7.org/fhir/us/davinci-drug-formulary/STU2.1