Preclinical Pharmacokinetics and Safety of Sym004: A Synergistic Antibody Mixture Directed against Epidermal Growth Factor Receptor

• Published in: Clinical cancer research Vol. 17; no. 18; pp. 5962 - 5972
• Main Authors: SKARTVED, Niels Jørgen Østergaard, JACOBSEN, Helle Jane, PEDERSEN, Mikkel Wandahl, JENSEN, Pernille Foged, SEN, Jette Wagtberg, JORGENSEN, Thomas Kjærsgaard, HEY, Adam, KRAGH, Michael
• Format: Journal Article
• Language: English
• Published: Philadelphia, PA American Association for Cancer Research 15.09.2011
• Subjects: Animals; Antibodies, Anti-Idiotypic - immunology; Antibodies, Monoclonal - administration & dosage; Antibodies, Monoclonal - pharmacokinetics; Antibodies, Monoclonal - toxicity; Antineoplastic agents; Antineoplastic Agents - administration & dosage; Antineoplastic Agents - pharmacokinetics; Antineoplastic Agents - toxicity; Biological and medical sciences; Cell Line, Tumor; Cross Reactions - immunology; Female; Guinea Pigs; Humans; Macaca fascicularis; Male; Medical sciences; Mice; Mice, Inbred BALB C; Mice, Nude; Pharmacology. Drug treatments; Rabbits; Rats; Receptor, Epidermal Growth Factor - antagonists & inhibitors; Xenograft Model Antitumor Assays; Growth factor receptor; Antibody; Toxicity; Preclinical trial; Safety; Pharmacokinetics; Mixture; Epidermal growth factor receptor
• ISSN: 1078-0432; 1557-3265
• DOI: 10.1158/1078-0432.ccr-11-1209

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. 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. 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. Sym004 was well tolerated and did not induce any unexpected toxicities. The preclinical safety data enabled initiation of the ongoing clinical development.