title: Development of a stable virus-like particle vaccine formulation against Chikungunya virus and investigation of the effects of polyanions.
abstract: Chikungunya virus (CHIKV) is an alphavirus that infects millions of people every year, especially in the developing world. The selective expression of recombinant CHIKV capsid and envelope proteins results in the formation of self-assembled virus-like particles (VLPs) that have been shown to protect nonhuman primates against infection from multiple strains of CHIKV. This study describes the characterization, excipient screening, and optimization of CHIKV VLP solution conditions toward the development of a stable parenteral formulation. The CHIKV VLPs were found to be poorly soluble at pH 6 and below. Circular dichroism, intrinsic fluorescence, and static and dynamic light scattering measurements were therefore performed at neutral pH, and results consistent with the formation of molten globule structures were observed at elevated temperatures. A library of generally recognized as safe excipients was screened for their ability to physically stabilize CHIKV VLPs using a high-throughput turbidity-based assay. Sugars, sugar alcohols, and polyanions were identified as potential stabilizers and the concentrations and combinations of select excipients were optimized. The effects of polyanions were further studied, and while all polyanions tested stabilized CHIKV VLPs against aggregation, the effects of polyanions on conformational stability varied.
authors.affiliation: Department of Pharmaceutical Chemistry, Macromolecule and Vaccine Stabilization Center, University of Kansas, Lawrence, Kansas, 66047.
authors.forename: Ryan M
authors.initials: RM
authors.lastname: Kramer
authors.forename: Yuhong
authors.initials: Y
authors.lastname: Zeng
authors.forename: Neha
authors.initials: N
authors.lastname: Sahni
authors.forename: Lisa A
authors.initials: LA
authors.lastname: Kueltzo
authors.forename: Richard M
authors.initials: RM
authors.lastname: Schwartz
authors.forename: Indresh K
authors.initials: IK
authors.lastname: Srivastava
authors.forename: Lindsey
authors.initials: L
authors.lastname: Crane
authors.forename: Sangeeta B
authors.initials: SB
authors.lastname: Joshi
authors.forename: David B
authors.initials: DB
authors.lastname: Volkin
authors.forename: C Russell
authors.initials: CR
authors.lastname: Middaugh
mesh_terms: D018354:Alphavirus Infections / Q000517:prevention & control / Q000821:virology; D000818:Animals; D065632:Chikungunya Fever; D002646:Chikungunya virus / Q000737:chemistry*; D002942:Circular Dichroism; D005079:Excipients / Q000737:chemistry*; D008027:Light; D009994:Osmolar Concentration; D010316:Particle Size; D000071228:Polyelectrolytes; D011108:Polymers / Q000737:chemistry*; D055550:Protein Stability; D012542:Scattering, Radiation; D058425:Vaccines, Virus-Like Particle / Q000737:chemistry*
chemical_list: D005079:Excipients; D000071228:Polyelectrolytes; D011108:Polymers; D058425:Vaccines, Virus-Like Particle
keywords: particle size; physical stability; physicochemical properties; preformulation; protein formulation; spectroscopy; stabilization; thermal analysis; vaccines