title: Identifying stabilizers of plasmid DNA for pharmaceutical use.
abstract: To better address the need for developing stable formulations of plasmid DNA-based biopharmaceuticals, 37 compounds from a generally regarded as safe library were examined for their potential use as stabilizers. A plasmid DNA-based therapeutic vaccine, BHT-DNA, was used as a model system. Initial studies were performed to compare the biophysical properties of BHT-DNA plasmid from bulk drug substance and finished drug product. An agarose gel electrophoresis-based assay was then employed in excipient compatibility studies for the drug product by monitoring supercoiled plasmid DNA content in various formulations. After incubation at 40 °C for 30 days, eight out of the 37 excipients tested were able to better retain the supercoil content compared to the control. Sodium citrate appeared to be the most effective stabilizer and its protective capability plateaued at an ionic strength of about 0.4. Several other excipients including malic acid, ethanol, and Pluronic F-68 were also identified as promising stabilizers for BHT-DNA plasmid DNA. Additionally, compounds, including ferrous chloride, ascorbic acid, human serum albumin, and PEG 1000, which significantly destabilized the supercoiled plasmid DNA were identified. These data may also be applicable to other plasmid DNA-based pharmaceuticals for storage stability improvement, due to chemical and structural similarities of these macromolecules.
authors.affiliation: Department of Pharmaceutical Chemistry, University of Kansas, Lawrence, Kansas 66047, USA.
authors.forename: Yuhong
authors.initials: Y
authors.lastname: Zeng
authors.forename: Joshua D
authors.initials: JD
authors.lastname: Ramsey
authors.forename: Robert
authors.initials: R
authors.lastname: King
authors.forename: Michael
authors.initials: M
authors.lastname: Leviten
authors.forename: Ruth
authors.initials: R
authors.lastname: Mcguire
authors.forename: David B
authors.initials: DB
authors.lastname: Volkin
authors.forename: Sangeeta B
authors.initials: SB
authors.lastname: Joshi
authors.forename: C Russell
authors.initials: CR
authors.lastname: Middaugh
mesh_terms: D002951:Citrates; D004247:DNA / Q000737:chemistry* / Q000627:therapeutic use; D004278:DNA, Superhelical / Q000737:chemistry / Q000627:therapeutic use; D004304:Dosage Forms; D004339:Drug Compounding; D004355:Drug Stability; D000431:Ethanol; D005079:Excipients; D057166:High-Throughput Screening Assays; D006801:Humans; D008293:Malates; D009994:Osmolar Concentration; D010957:Plasmids; D020442:Poloxamer; D000077559:Sodium Citrate; D019444:Vaccines, DNA / Q000737:chemistry* / Q000627:therapeutic use
chemical_list: D002951:Citrates; D004278:DNA, Superhelical; D004304:Dosage Forms; D005079:Excipients; D008293:Malates; D019444:Vaccines, DNA; D020442:Poloxamer; D000077559:Sodium Citrate; D000431:Ethanol; C030298:malic acid; D004247:DNA