RT Journal Article SR Electronic T1 Generation and Activity of a Humanized Monoclonal Antibody That Selectively Neutralizes the Epidermal Growth Factor Receptor Ligands Transforming Growth Factor-α and Epiregulin JF Journal of Pharmacology and Experimental Therapeutics JO J Pharmacol Exp Ther FD American Society for Pharmacology and Experimental Therapeutics SP 330 OP 343 DO 10.1124/jpet.113.210765 VO 349 IS 2 A1 Catherine B. Beidler A1 Ramona J. Petrovan A1 Elaine M. Conner A1 Jeffrey S. Boyles A1 Derek D. Yang A1 Shannon M. Harlan A1 Shaoyou Chu A1 Bernice Ellis A1 Amita Datta-Mannan A1 Robert L. Johnson A1 Anja Stauber A1 Derrick R. Witcher A1 Matthew D. Breyer A1 Josef G. Heuer YR 2014 UL http://jpet.aspetjournals.org/content/349/2/330.abstract AB At least seven distinct epidermal growth factor (EGF) ligands bind to and activate the EGF receptor (EGFR). This activation plays an important role in the embryo and in the maintenance of adult tissues. Importantly, pharmacologic EGFR inhibition also plays a critical role in the pathophysiology of diverse disease states, especially cancer. The roles of specific EGFR ligands are poorly defined in these disease states. Accumulating evidence suggests a role for transforming growth factor α (TGFα) in skin, lung, and kidney disease. To explore the role of Tgfa, we generated a monoclonal antibody (mAb41) that binds to and neutralizes human Tgfa with high affinity (KD = 36.5 pM). The antibody also binds human epiregulin (Ereg) (KD = 346.6 pM) and inhibits ligand induced myofibroblast cell proliferation (IC50 values of 0.52 and 1.12 nM for human Tgfa and Ereg, respectively). In vivo, a single administration of the antibody to pregnant mice (30 mg/kg s.c. at day 14 after plug) or weekly administration to neonate mice (20 mg/kg s.c. for 4 weeks) phenocopy Tgfa knockout mice with curly whiskers, stunted growth, and expansion of the hypertrophic zone of growth plate cartilage. Humanization of this monoclonal antibody to a human IgG4 antibody (LY3016859) enables clinical development. Importantly, administration of the humanized antibody to cynomolgus monkeys is absent of the skin toxicity observed with current EGFR inhibitors used clinically and no other pathologies were noted, indicating that neutralization of Tgfa could provide a relatively safe profile as it advances in clinical development.