title: Optimizing storage stability of lyophilized recombinant human interleukin-11 with disaccharide/hydroxyethyl starch mixtures.
abstract: Optimal storage stability of a protein in a dry formulation depends on the storage temperature relative to the glass transition temperature (T(g)) of the dried formulation and the structure of the dried protein. We tested the hypothesis that optimizing both protein structure and T(g)--by freeze-drying recombinant human interleukin-11 (rhIL-11) with mixtures of disaccharides and hydroxyethyl starch (HES)--would result in increased storage stability compared with the protein lyophilized with either disaccharide or hydroxyethyl starch alone. The secondary structure of the protein in the dried solid was analyzed immediately after lyophilization and after storage at elevated temperatures by infrared spectroscopy. After rehydration, aggregation was monitored by size exclusion chromatography. Oxidation levels and cleavage products were quantified by reversed-phase chromatography. For the formulation with HES alone, which has a relatively high T(g), storage stability of rhIL-11 was poor, because HES failed to inhibit lyophilization-induced unfolding. The sugar formulations inhibited unfolding, and had intermediate T(g) values and storage stabilities. Addition of hydroxyethyl starch to sucrose or trehalose increased T(g) without affecting the capacity of the sugar to inhibit protein unfolding during lyophilization. Optimal storage stability of lyophilized rhIL-11 was achieved by using a mixture of disaccharide and polymeric carbohydrates.
authors.affiliation: Center for Pharmaceutical Biotechnology, School of Pharmacy, University of Colorado Health Sciences Center, Denver, CO 80262, USA.
authors.forename: William
authors.initials: W
authors.lastname: Garzon-Rodriguez
authors.forename: Rebecca L
authors.initials: RL
authors.lastname: Koval
authors.forename: Suchart
authors.initials: S
authors.lastname: Chongprasert
authors.forename: Sampathkumar
authors.initials: S
authors.lastname: Krishnan
authors.forename: Theodore W
authors.initials: TW
authors.lastname: Randolph
authors.forename: Nicholas W
authors.initials: NW
authors.lastname: Warne
authors.forename: John F
authors.initials: JF
authors.lastname: Carpenter
mesh_terms: D004187:Disaccharides / Q000032:analysis / Q000737:chemistry*; D004355:Drug Stability; D004356:Drug Storage; D005612:Freeze Drying / Q000379:methods; D006801:Humans; D006895:Hydroxyethyl Starch Derivatives / Q000032:analysis / Q000737:chemistry*; D017370:Interleukin-11 / Q000032:analysis / Q000737:chemistry*; D011994:Recombinant Proteins / Q000032:analysis / Q000737:chemistry
chemical_list: D004187:Disaccharides; D006895:Hydroxyethyl Starch Derivatives; D017370:Interleukin-11; D011994:Recombinant Proteins