{description: Accesses the subject FormularyDrug (MedicationKnowledge) reference of a FormularyItem, package_name: hl7.fhir.us.davinci-drug-formulary, name: USDFBasicSubject, type: reference, package_version: 2.0.1, class: unknown, kind: null, url: 'http://hl7.org/fhir/us/davinci-drug-formulary/SearchParameter/Basic-subject', version: 2.0.1}