title: Preclinical pharmacokinetics and safety of Sym004: a synergistic antibody mixture directed against epidermal growth factor receptor.
abstract: OBJECTIVE
  Sym004 is a novel therapeutic antibody mixture product comprising two unmarketed monoclonal antibodies (mAb) targeting the epidermal growth factor receptor (EGFR). In previous preclinical proof-of-concept studies, Sym004 was shown to elicit superior cancer cell growth inhibition activities compared with marketed anti-EGFR mAbs. This article describes the design and results of the preclinical safety program conducted to support early clinical development of Sym004.
  
  
  METHODS
  Tissue cryosections from various species were stained with Sym004 to evaluate tissue cross reactivity. The pharmacokinetics of Sym004 were evaluated in a mouse xenograft model and in Cynomolgus monkeys. Monkeys received once weekly intravenous infusions of Sym004 in the range 2 to 24 mg/kg for 6 to 8 weeks. Cetuximab (a marketed anti-EGFR mAb) and the individual antibodies comprising Sym004 were included in the repeat-dose toxicity studies at single-dose level.
  
  
  RESULTS
  Sym004 had a staining pattern similar to cetuximab in tissue panels from both human and non-human primates. Once weekly dosing of Sym004 to Cynomolgus monkeys did not cause accumulation, whereas administration of the individual antibodies resulted in prolonged half-life and accumulation. In direct comparisons with cetuximab, Sym004 did not induce any distinct or novel adverse findings in the animals. However, an early onset of pronounced, reversible, and anticipated anti-EGFR-mediated pharmacologic effects, such as skin rash, dehydration, and liquid feces, was observed. Only minor adverse effects were recorded in animals treated with the individual antibodies comprising Sym004.
  
  
  CONCLUSIONS
  Sym004 was well tolerated and did not induce any unexpected toxicities. The preclinical safety data enabled initiation of the ongoing clinical development.
authors.affiliation: Symphogen A/S, Lyngby, Denmark. nsk@symphogen.com
authors.forename: Niels Jørgen Østergaard
authors.initials: NJ
authors.lastname: Skartved
authors.forename: Helle Jane
authors.initials: HJ
authors.lastname: Jacobsen
authors.forename: Mikkel Wandahl
authors.initials: MW
authors.lastname: Pedersen
authors.forename: Pernille Foged
authors.initials: PF
authors.lastname: Jensen
authors.forename: Jette Wagtberg
authors.initials: JW
authors.lastname: Sen
authors.forename: Thomas Kjærsgaard
authors.initials: TK
authors.lastname: Jørgensen
authors.forename: Adam
authors.initials: A
authors.lastname: Hey
authors.forename: Michael
authors.initials: M
authors.lastname: Kragh
mesh_terms: D000818:Animals; D000888:Antibodies, Anti-Idiotypic / Q000276:immunology; D000911:Antibodies, Monoclonal / Q000008:administration & dosage / Q000493:pharmacokinetics* / Q000633:toxicity; D000970:Antineoplastic Agents / Q000008:administration & dosage / Q000493:pharmacokinetics* / Q000633:toxicity; D045744:Cell Line, Tumor; D003429:Cross Reactions / Q000276:immunology; D066246:ErbB Receptors / Q000037:antagonists & inhibitors*; D005260:Female; D006168:Guinea Pigs; D006801:Humans; D008252:Macaca fascicularis; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D011817:Rabbits; D051381:Rats; D023041:Xenograft Model Antitumor Assays
chemical_list: D000888:Antibodies, Anti-Idiotypic; D000911:Antibodies, Monoclonal; D000970:Antineoplastic Agents; C569270:futuximab; D066246:ErbB Receptors