Phase I, pharmacokinetic, and pharmacodynamic study of AMG 479, a fully human monoclonal antibody to insulin-like growth factor receptor 1.
OBJECTIVE
To determine the maximum-tolerated dose (MTD) and to assess the safety, pharmacokinetics, and evidence of antitumor activity of AMG 479, a fully human monoclonal antibody to insulin-like growth factor receptor 1 (IGF-1R).


METHODS
Patients with advanced solid malignancies or non-Hodgkin's lymphoma received escalating doses of AMG 479 intravenously (IV) every 2 weeks (Q2W). Blood samples were assayed to determine pharmacokinetic parameters and IGF-1R occupancy on neutrophils; fluorodeoxyglucose-positron emission tomography scans were used to assess tumor metabolic effects.


RESULTS
Fifty-three patients received 312 infusions of AMG 479 Q2W. Overall, the most common grades 1 to 2 toxicities were fatigue, thrombocytopenia, fever, rash, chills, and anorexia. One dose-limiting toxicity (ie, grade 3 thrombocytopenia) occurred in a patient at 20 mg/kg during course 1; grade 3 thrombocytopenia (n = 8) and grade 3 transaminitis elevations (n = 1) also were reported but not in the escalation phase. The maximum-planned dose of 20 mg/kg was safely administered; thus, an MTD was not reached. High levels of neutrophil IGF-1R binding and increases from baseline in serum IGF-1 levels were observed in the 12- and 20-mg/kg cohorts. Tumor responses included one durable complete response (CR) and one unconfirmed partial response (PR) in two patients with Ewing/primitive neuroectodermal tumors and included one PR and one minor response in two patients with neuroendocrine tumors. The patients with Ewing/PNET who had a CR have remained disease free on therapy after 28 months.


CONCLUSIONS
AMG 479 can be administered safely at 20 mg/kg IV Q2W. The absence of severe toxicities, attainment of serum concentrations associated with high levels of IGF-1R binding on neutrophils, and provocative antitumor activity warrant additional studies of this agent.
South Texas Accelerated Research Therapeutics, San Antonio, TX 78229, USA. atolcher@start.stoh.com
Anthony W
AW
Tolcher
John
J
Sarantopoulos
Amita
A
Patnaik
Kyriakos
K
Papadopoulos
Chia-Chi
CC
Lin
Jordi
J
Rodon
Barbara
B
Murphy
Bruce
B
Roth
Ian
I
McCaffery
Kevin S
KS
Gorski
Brianne
B
Kaiser
Min
M
Zhu
Hongjie
H
Deng
Greg
G
Friberg
Igor
I
Puzanov
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000911:Antibodies, Monoclonal / Q000009:adverse effects / Q000493:pharmacokinetics / Q000494:pharmacology / Q000627:therapeutic use*; D061067:Antibodies, Monoclonal, Humanized; D005260:Female; D006801:Humans; D007262:Infusions, Intravenous; D008297:Male; D020714:Maximum Tolerated Dose; D008875:Middle Aged; D009369:Neoplasms / Q000188:drug therapy*; D009504:Neutrophils / Q000378:metabolism; D017526:Receptor, IGF Type 1 / Q000276:immunology* / Q000378:metabolism; D055815:Young Adult
D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; C545764:ganitumab; D017526:Receptor, IGF Type 1