title: Antibody-Drug Conjugates (ADCs) Derived from Interchain Cysteine Cross-Linking Demonstrate Improved Homogeneity and Other Pharmacological Properties over Conventional Heterogeneous ADCs.
abstract: Conventional antibody-drug conjugates (ADCs) are heterogeneous mixtures of chemically distinct molecules that vary in both drugs/antibody (DAR) and conjugation sites. Suboptimal properties of heterogeneous ADCs have led to new site-specific conjugation methods for improving ADC homogeneity. Most site-specific methods require extensive antibody engineering to identify optimal conjugation sites and introduce unique functional groups for conjugation with appropriately modified linkers. Alternative nonrecombinant methods have emerged in which bifunctional linkers are utilized to cross-link antibody interchain cysteines and afford ADCs containing four drugs/antibody. Although these methods have been shown to improve ADC homogeneity and stability in vitro, their effect on the pharmacological properties of ADCs in vivo is unknown. In order to determine the relative impact of interchain cysteine cross-linking on the therapeutic window and other properties of ADCs in vivo, we synthesized a derivative of the known ADC payload, MC-MMAF, that contains a bifunctional dibromomaleimide (DBM) linker instead of a conventional maleimide (MC) linker. The DBM-MMAF derivative was conjugated to trastuzumab and a novel anti-CD98 antibody to afford ADCs containing predominantly four drugs/antibody. The pharmacological properties of the resulting cross-linked ADCs were compared with analogous heterogeneous ADCs derived from conventional linkers. The results demonstrate that DBM linkers can be applied directly to native antibodies, without antibody engineering, to yield highly homogeneous ADCs via cysteine cross-linking. The resulting ADCs demonstrate improved pharmacokinetics, superior efficacy, and reduced toxicity in vivo compared to analogous conventional heterogeneous ADCs.
authors.affiliation: Igenica Biotherapeutics , 863A Mitten Road, Suite 100B, Burlingame, California 94010, United States.
authors.forename: Christopher R
authors.initials: CR
authors.lastname: Behrens
authors.affiliation: Igenica Biotherapeutics , 863A Mitten Road, Suite 100B, Burlingame, California 94010, United States.
authors.forename: Edward H
authors.initials: EH
authors.lastname: Ha
authors.affiliation: Igenica Biotherapeutics , 863A Mitten Road, Suite 100B, Burlingame, California 94010, United States.
authors.forename: Lawrence L
authors.initials: LL
authors.lastname: Chinn
authors.affiliation: Igenica Biotherapeutics , 863A Mitten Road, Suite 100B, Burlingame, California 94010, United States.
authors.forename: Simeon
authors.initials: S
authors.lastname: Bowers
authors.affiliation: Igenica Biotherapeutics , 863A Mitten Road, Suite 100B, Burlingame, California 94010, United States.
authors.forename: Gary
authors.initials: G
authors.lastname: Probst
authors.affiliation: Igenica Biotherapeutics , 863A Mitten Road, Suite 100B, Burlingame, California 94010, United States.
authors.forename: Maureen
authors.initials: M
authors.lastname: Fitch-Bruhns
authors.affiliation: Igenica Biotherapeutics , 863A Mitten Road, Suite 100B, Burlingame, California 94010, United States.
authors.forename: Jorge
authors.initials: J
authors.lastname: Monteon
authors.affiliation: Igenica Biotherapeutics , 863A Mitten Road, Suite 100B, Burlingame, California 94010, United States.
authors.forename: Amanda
authors.initials: A
authors.lastname: Valdiosera
authors.affiliation: Igenica Biotherapeutics , 863A Mitten Road, Suite 100B, Burlingame, California 94010, United States.
authors.forename: Abel
authors.initials: A
authors.lastname: Bermudez
authors.affiliation: Igenica Biotherapeutics , 863A Mitten Road, Suite 100B, Burlingame, California 94010, United States.
authors.forename: Sindy
authors.initials: S
authors.lastname: Liao-Chan
authors.affiliation: Igenica Biotherapeutics , 863A Mitten Road, Suite 100B, Burlingame, California 94010, United States.
authors.forename: Tiffany
authors.initials: T
authors.lastname: Wong
authors.affiliation: Igenica Biotherapeutics , 863A Mitten Road, Suite 100B, Burlingame, California 94010, United States.
authors.forename: Jonathan
authors.initials: J
authors.lastname: Melnick
authors.affiliation: Igenica Biotherapeutics , 863A Mitten Road, Suite 100B, Burlingame, California 94010, United States.
authors.forename: Jan-Willem
authors.initials: JW
authors.lastname: Theunissen
authors.affiliation: Igenica Biotherapeutics , 863A Mitten Road, Suite 100B, Burlingame, California 94010, United States.
authors.forename: Mark R
authors.initials: MR
authors.lastname: Flory
authors.affiliation: Igenica Biotherapeutics , 863A Mitten Road, Suite 100B, Burlingame, California 94010, United States.
authors.forename: Derrick
authors.initials: D
authors.lastname: Houser
authors.affiliation: Igenica Biotherapeutics , 863A Mitten Road, Suite 100B, Burlingame, California 94010, United States.
authors.forename: Kristy
authors.initials: K
authors.lastname: Venstrom
authors.affiliation: Igenica Biotherapeutics , 863A Mitten Road, Suite 100B, Burlingame, California 94010, United States.
authors.forename: Zoia
authors.initials: Z
authors.lastname: Levashova
authors.affiliation: Igenica Biotherapeutics , 863A Mitten Road, Suite 100B, Burlingame, California 94010, United States.
authors.forename: Paul
authors.initials: P
authors.lastname: Sauer
authors.affiliation: Igenica Biotherapeutics , 863A Mitten Road, Suite 100B, Burlingame, California 94010, United States.
authors.forename: Thi-Sau
authors.initials: TS
authors.lastname: Migone
authors.affiliation: Igenica Biotherapeutics , 863A Mitten Road, Suite 100B, Burlingame, California 94010, United States.
authors.forename: Edward H
authors.initials: EH
authors.lastname: van der Horst
authors.affiliation: Igenica Biotherapeutics , 863A Mitten Road, Suite 100B, Burlingame, California 94010, United States.
authors.forename: Randall L
authors.initials: RL
authors.lastname: Halcomb
authors.affiliation: Igenica Biotherapeutics , 863A Mitten Road, Suite 100B, Burlingame, California 94010, United States.
authors.forename: David Y
authors.initials: DY
authors.lastname: Jackson
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000737:chemistry / Q000494:pharmacology*; D000970:Antineoplastic Agents / Q000737:chemistry / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects; D015153:Blotting, Western; D049109:Cell Proliferation / Q000187:drug effects; D003432:Cross-Linking Reagents; D003545:Cysteine / Q000737:chemistry*; D005260:Female; D005434:Flow Cytometry; D005455:Fluorescent Antibody Technique; D027261:Fusion Regulatory Protein-1 / Q000276:immunology; D006801:Humans; D018796:Immunoconjugates / Q000737:chemistry / Q000494:pharmacology*; D008175:Lung Neoplasms / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D008297:Male; D051379:Mice; D016688:Mice, Inbred NOD; D016513:Mice, SCID; D051381:Rats; D017207:Rats, Sprague-Dawley; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000037:antagonists & inhibitors; D000068878:Trastuzumab / Q000737:chemistry / Q000494:pharmacology*; D014407:Tumor Cells, Cultured; D023041:Xenograft Model Antitumor Assays
chemical_list: D000911:Antibodies, Monoclonal; D000970:Antineoplastic Agents; D003432:Cross-Linking Reagents; D003545:Cysteine; D027261:Fusion Regulatory Protein-1; D018796:Immunoconjugates; D018719:Erb-b2 Receptor Tyrosine Kinases; D000068878:Trastuzumab
keywords: ADC; CD98; DAR; Her2; MMAF; antibody−drug conjugate; auristatin; bifunctional; conjugation; cysteine; dibromomaleimide; disulfide; hinge; homogeneous; interchain; linker; maleimide; site-specific; trastuzumab