title: Biowaiver monographs for immediate release solid oral dosage forms: quinidine sulfate.
abstract: Literature data are reviewed relevant to the decision to allow a waiver of in vivo bioequivalence (BE) testing for the approval of new multisource and reformulated immediate release (IR) solid oral dosage forms containing quinidine sulfate. Quinidine sulfate's solubility and permeability, its therapeutic use and index, pharmacokinetics, excipient interactions and reported BE/bioavailability (BA) problems were taken into consideration. The available data are not fully conclusive, but do suggest that quinidine sulfate is highly soluble and moderately to highly permeable and would likely be assigned to BCS Class I (or at worst BCS III). In view of the inconclusiveness of the data and, more important, quinidine's narrow therapeutic window and critical indication, a biowaiver based approval of quinidine containing dosage forms cannot be recommended for either new multisource drug products or for major postapproval changes (variations) to existing drug products.
authors.affiliation: Institute of Pharmacy, Department of Biopharmaceutics and Pharmaceutical Technology, Johannes Gutenberg-University, Mainz, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Grube
authors.forename: P
authors.initials: P
authors.lastname: Langguth
authors.forename: H E
authors.initials: HE
authors.lastname: Junginger
authors.forename: S
authors.initials: S
authors.lastname: Kopp
authors.forename: K K
authors.initials: KK
authors.lastname: Midha
authors.forename: V P
authors.initials: VP
authors.lastname: Shah
authors.forename: S
authors.initials: S
authors.lastname: Stavchansky
authors.forename: J B
authors.initials: JB
authors.lastname: Dressman
authors.forename: D M
authors.initials: DM
authors.lastname: Barends
mesh_terms: D000284:Administration, Oral; D000889:Anti-Arrhythmia Agents / Q000008:administration & dosage* / Q000737:chemistry / Q000493:pharmacokinetics* / Q000627:therapeutic use; D000962:Antimalarials / Q000008:administration & dosage* / Q000737:chemistry / Q000493:pharmacokinetics* / Q000627:therapeutic use; D001682:Biological Availability; D004304:Dosage Forms; D017277:Drug Approval; D005079:Excipients; D006801:Humans; D010539:Permeability; D011802:Quinidine / Q000008:administration & dosage* / Q000737:chemistry / Q000493:pharmacokinetics* / Q000627:therapeutic use; D012995:Solubility; D013810:Therapeutic Equivalency
chemical_list: D000889:Anti-Arrhythmia Agents; D000962:Antimalarials; D004304:Dosage Forms; D005079:Excipients; D011802:Quinidine