title: A CD80-Biased CTLA4-Ig Fusion Protein with Superior In Vivo Efficacy by Simultaneous Engineering of Affinity, Selectivity, Stability, and FcRn Binding.
abstract: Affinity- and stability-engineered variants of CTLA4-Ig fusion molecules with enhanced pharmacokinetic profiles could yield improved therapies with the potential of higher efficacy and greater convenience to patients. In this study, to our knowledge, we have, for the first time, used in vitro evolution to simultaneously optimize CTLA4 affinity and stability. We selected for improved binding to both ligands, CD80 and CD86, and screened as dimeric Fc fusions directly in functional assays to identify variants with stronger suppression of in vitro T cell activation. The majority of CTLA4 molecules showing the largest potency gains in primary in vitro and ex vivo human cell assays, using PBMCs from type 1 diabetes patients, had significant improvements in CD80, but only modest gains in CD86 binding. We furthermore observed different potency rankings between our lead molecule MEDI5265, abatacept, and belatacept, depending on which type of APC was used, with MEDI5265 consistently being the most potent. We then created fusions of both stability- and potency-optimized CTLA4 moieties with human Fc variants conferring extended plasma t1/2In a cynomolgus model of T cell-dependent Ab response, the CTLA4-Ig variant MEDI5265 could be formulated at >100 mg/ml for s.c. administration and showed superior efficacy and significantly prolonged serum t1/2The combination of higher stability and potency with prolonged pharmacokinetics could be compatible with very infrequent, s.c. dosing while maintaining a similar level of immune suppression to more frequently and i.v. administered licensed therapies.
authors.affiliation: MedImmune, Cambridge CB21 6GH, United Kingdom.
authors.forename: Julie
authors.initials: J
authors.lastname: Douthwaite
authors.affiliation: MedImmune, Gaithersburg, MD 20878.
authors.forename: Jacques
authors.initials: J
authors.lastname: Moisan
authors.affiliation: MedImmune, Cambridge CB21 6GH, United Kingdom.
authors.forename: Cyril
authors.initials: C
authors.lastname: Privezentzev
authors.affiliation: Royal Free Campus, Institute of Immunity and Transplantation, University College London, London NW3 2PF, United Kingdom.
authors.forename: Blagoje
authors.initials: B
authors.lastname: Soskic
authors.affiliation: Department of Immunobiology, King's College London, London SE1 9RT, United Kingdom.|Faculty of Life Sciences and Medicine, King's College London, London SE1 9RT, United Kingdom.|National Institutes of Health Research Biomedical Research Centre at Guy's and St. Thomas' National Health Service Foundation Trust, London SE1 9RT, United Kingdom; and.
authors.forename: Shereen
authors.initials: S
authors.lastname: Sabbah
authors.affiliation: MedImmune, Cambridge CB21 6GH, United Kingdom.
authors.forename: Suzanne
authors.identifier: 0000-0002-4470-1680
authors.initials: S
authors.lastname: Cohen
authors.affiliation: MedImmune, Cambridge CB21 6GH, United Kingdom.
authors.forename: Andie
authors.identifier: 0000-0001-7465-8313
authors.initials: A
authors.lastname: Collinson
authors.affiliation: MedImmune, Cambridge CB21 6GH, United Kingdom.
authors.forename: Elizabeth
authors.identifier: 0000-0001-9581-0046
authors.initials: E
authors.lastname: England
authors.affiliation: MedImmune, Cambridge CB21 6GH, United Kingdom.
authors.forename: Catherine
authors.identifier: 0000-0003-3193-9320
authors.initials: C
authors.lastname: Huntington
authors.affiliation: MedImmune, Cambridge CB21 6GH, United Kingdom.
authors.forename: Ben
authors.identifier: 0000-0002-7523-5766
authors.initials: B
authors.lastname: Kemp
authors.affiliation: MedImmune, Gaithersburg, MD 20878.
authors.forename: Li
authors.initials: L
authors.lastname: Zhuang
authors.affiliation: MedImmune, Gaithersburg, MD 20878.
authors.forename: Suzanne
authors.identifier: 0000-0001-9666-7499
authors.initials: S
authors.lastname: Hudak
authors.affiliation: MedImmune, Cambridge CB21 6GH, United Kingdom.
authors.forename: D Gareth
authors.initials: DG
authors.lastname: Rees
authors.affiliation: MedImmune, Gaithersburg, MD 20878.
authors.forename: Debbie
authors.initials: D
authors.lastname: Goldberg
authors.affiliation: MedImmune, Gaithersburg, MD 20878.
authors.forename: Chris
authors.initials: C
authors.lastname: Barton
authors.affiliation: MedImmune, Mountain View, CA 94043.
authors.forename: Linda
authors.identifier: 0000-0002-4974-6503
authors.initials: L
authors.lastname: Chang
authors.affiliation: MedImmune, Mountain View, CA 94043.
authors.forename: Inna
authors.initials: I
authors.lastname: Vainshtein
authors.affiliation: MedImmune, Mountain View, CA 94043.
authors.forename: Meina
authors.initials: M
authors.lastname: Liang
authors.affiliation: MedImmune, Gaithersburg, MD 20878.
authors.forename: Laurie
authors.initials: L
authors.lastname: Iciek
authors.affiliation: MedImmune, Cambridge CB21 6GH, United Kingdom.
authors.forename: Philip
authors.initials: P
authors.lastname: Ambery
authors.affiliation: Department of Immunobiology, King's College London, London SE1 9RT, United Kingdom.|Faculty of Life Sciences and Medicine, King's College London, London SE1 9RT, United Kingdom.|National Institutes of Health Research Biomedical Research Centre at Guy's and St. Thomas' National Health Service Foundation Trust, London SE1 9RT, United Kingdom; and.
authors.forename: Mark
authors.initials: M
authors.lastname: Peakman
authors.affiliation: MedImmune, Cambridge CB21 6GH, United Kingdom.
authors.forename: Tristan J
authors.identifier: 0000-0002-3652-8232
authors.initials: TJ
authors.lastname: Vaughan
authors.affiliation: Department of Immunobiology, King's College London, London SE1 9RT, United Kingdom.|Faculty of Life Sciences and Medicine, King's College London, London SE1 9RT, United Kingdom.|National Institutes of Health Research Biomedical Research Centre at Guy's and St. Thomas' National Health Service Foundation Trust, London SE1 9RT, United Kingdom; and.
authors.forename: Tim I M
authors.identifier: 0000-0002-6973-5377
authors.initials: TI
authors.lastname: Tree
authors.affiliation: Royal Free Campus, Institute of Immunity and Transplantation, University College London, London NW3 2PF, United Kingdom.
authors.forename: David M
authors.identifier: 0000-0001-6506-3115
authors.initials: DM
authors.lastname: Sansom
authors.affiliation: MedImmune, Gaithersburg, MD 20878.
authors.forename: Michael A
authors.initials: MA
authors.lastname: Bowen
authors.affiliation: MedImmune, Cambridge CB21 6GH, United Kingdom.
authors.forename: Ralph R
authors.identifier: 0000-0001-5571-3102
authors.initials: RR
authors.lastname: Minter
authors.affiliation: MedImmune, Cambridge CB21 6GH, United Kingdom; jermutusl@medimmune.com.
authors.forename: Lutz
authors.initials: L
authors.lastname: Jermutus
mesh_terms: D000069594:Abatacept / Q000737:chemistry / Q000494:pharmacology*; D000818:Animals; D018122:B7-1 Antigen / Q000276:immunology; D051940:B7-2 Antigen; D015195:Drug Design; D004355:Drug Stability; D006801:Humans; D007166:Immunosuppressive Agents / Q000737:chemistry / Q000494:pharmacology*; D011485:Protein Binding / Q000276:immunology
chemical_list: D018122:B7-1 Antigen; D051940:B7-2 Antigen; D007166:Immunosuppressive Agents; D000069594:Abatacept