title: The effect of arginine glutamate on the stability of monoclonal antibodies in solution.
abstract: Finding excipients which mitigate protein self-association and aggregation is an important task during formulation. Here, the effect of an equimolar mixture of l-Arg and l-Glu (Arg·Glu) on colloidal and conformational stability of four monoclonal antibodies (mAb1-mAb4) at different pH is explored, with the temperatures of the on-set of aggregation (Tagg) and unfolding (Tm1) measured by static light scattering and intrinsic fluorescence, respectively. Arg·Glu increased the Tagg of all four mAbs in concentration-dependent manner, especially as pH increased to neutral. Arg·Glu also increased Tm1 of the least thermally stable mAb3, but without similar direct effect on the Tm1 of other mAbs. Raising pH itself from 5 to 7 increased Tm1 for all four mAbs. Selected mAb formulations were assessed under accelerated stability conditions for the monomer fraction remaining in solution after storage. The aggregation of mAb3 was suppressed to a greater extent by Arg·Glu than by Arg·HCl. Furthermore, Arg·Glu suppressed the aggregation of mAb1 at neutral pH such that the fraction monomer was near to that at the more typical formulation pH of 5.5. We conclude that Arg·Glu can suppress mAb aggregation with increasing temperature/pH and, importantly, under accelerated stability conditions at weakly acidic to neutral pH.
authors.affiliation: Manchester Institute of Biotechnology, University of Manchester, Manchester M1 7DN, UK; Faculty of Life Sciences, University of Manchester, Manchester M13 9PL, UK.
authors.forename: Priscilla
authors.initials: P
authors.lastname: Kheddo
authors.affiliation: MedImmune Ltd., Granta Park, Cambridge CB21 6GH, UK.
authors.forename: Malgorzata
authors.initials: M
authors.lastname: Tracka
authors.affiliation: MedImmune Ltd., Granta Park, Cambridge CB21 6GH, UK.
authors.forename: Jonathan
authors.initials: J
authors.lastname: Armer
authors.affiliation: Faculty of Life Sciences, University of Manchester, Manchester M13 9PL, UK.
authors.forename: Rebecca J
authors.initials: RJ
authors.lastname: Dearman
authors.affiliation: MedImmune Ltd., Granta Park, Cambridge CB21 6GH, UK.
authors.forename: Shahid
authors.initials: S
authors.lastname: Uddin
authors.affiliation: MedImmune Ltd., Granta Park, Cambridge CB21 6GH, UK.
authors.forename: Christopher F
authors.initials: CF
authors.lastname: van der Walle
authors.affiliation: Manchester Institute of Biotechnology, University of Manchester, Manchester M1 7DN, UK; Faculty of Life Sciences, University of Manchester, Manchester M13 9PL, UK. Electronic address: A.Golovanov@manchester.ac.uk.
authors.forename: Alexander P
authors.initials: AP
authors.lastname: Golovanov
mesh_terms: D000911:Antibodies, Monoclonal / Q000737:chemistry*; D004151:Dipeptides / Q000737:chemistry*; D005079:Excipients / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D007074:Immunoglobulin G / Q000737:chemistry*; D009994:Osmolar Concentration; D066329:Protein Aggregates; D011487:Protein Conformation; D055550:Protein Stability; D058767:Protein Unfolding; D012996:Solutions; D013696:Temperature
chemical_list: D000911:Antibodies, Monoclonal; D004151:Dipeptides; D005079:Excipients; D007074:Immunoglobulin G; D066329:Protein Aggregates; D012996:Solutions; C024362:arginine glutamate
keywords: Excipients; Physical characterization; Physical stability; Protein aggregation; mAbs formulation