title: Preclinical Development of an anti-5T4 Antibody-Drug Conjugate: Pharmacokinetics in Mice, Rats, and NHP and Tumor/Tissue Distribution in Mice.
abstract: The pharmacokinetics of an antibody (huA1)-drug (auristatin microtubule disrupting MMAF) conjugate, targeting 5T4-expressing cells, were characterized during the discovery and development phases in female nu/nu mice and cynomolgus monkeys after a single dose and in S-D rats and cynomolgus monkeys from multidose toxicity studies. Plasma/serum samples were analyzed using an ELISA-based method for antibody and conjugate (ADC) as well as for the released payload using an LC-MS/MS method. In addition, the distribution of the Ab, ADC, and released payload (cys-mcMMAF) was determined in a number of tissues (tumor, lung, liver, kidney, and heart) in two tumor mouse models (H1975 and MDA-MB-361-DYT2 models) using similar LBA and LC-MS/MS methods. Tissue distribution studies revealed preferential tumor distribution of cys-mcMMAF and its relative specificity to the 5T4 target containing tissue (tumor). Single dose studies suggests lower CL values at the higher doses in mice, although a linear relationship was seen in cynomolgus monkeys at doses from 0.3 to 10 mg/kg with no evidence of TMDD. Evaluation of DAR (drug-antibody ratio) in cynomolgus monkeys (at 3 mg/kg) indicated that at least half of the payload was still on the ADC 1 to 2 weeks after IV dosing. After multiple doses, the huA1 and conjugate data in rats and monkeys indicate that exposure (AUC) increases with increasing dose in a linear fashion. Systemic exposure (as assessed by Cmax and AUC) of the released payload increased with increasing dose, although exposure was very low and its pharmacokinetics appeared to be formation rate limited. The incidence of ADA was generally low in rats and monkeys. We will discuss cross species comparison, relationships between the Ab, ADC, and released payload exposure after multiple dosing, and insights into the distribution of this ADC with a focus on experimental design as a way to address or bypass apparent obstacles and its integration into predictive models.
authors.affiliation: Pharmacokinetics, Dynamics and Metabolism, Pfizer Inc. , Pearl River, New York 10965, United States.
authors.forename: Mauricio
authors.initials: M
authors.lastname: Leal
authors.affiliation: Pharmacokinetics, Dynamics and Metabolism, Pfizer Inc. , Groton, Connecticut 06340, United States.
authors.forename: JoAnn
authors.initials: J
authors.lastname: Wentland
authors.affiliation: Pharmacokinetics, Dynamics and Metabolism, Pfizer Inc. , Groton, Connecticut 06340, United States.
authors.forename: Xiaogang
authors.initials: X
authors.lastname: Han
authors.affiliation: Pharmacokinetics, Dynamics and Metabolism, Pfizer Inc. , Groton, Connecticut 06340, United States.
authors.forename: Yanhua
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Pharmacokinetics, Dynamics and Metabolism, Pfizer Inc. , Groton, Connecticut 06340, United States.
authors.forename: Brian
authors.initials: B
authors.lastname: Rago
authors.affiliation: Pharmacokinetics, Dynamics and Metabolism, Pfizer Inc. , Andover, Massachusetts 01810, United States.
authors.forename: Nicole
authors.initials: N
authors.lastname: Duriga
authors.affiliation: Pharmacokinetics, Dynamics and Metabolism, Pfizer Inc. , Andover, Massachusetts 01810, United States.
authors.forename: Franklin
authors.initials: F
authors.lastname: Spriggs
authors.affiliation: Pharmacokinetics, Dynamics and Metabolism, Pfizer Inc. , Groton, Connecticut 06340, United States.
authors.forename: Eugene
authors.initials: E
authors.lastname: Kadar
authors.affiliation: Pharmacokinetics, Dynamics and Metabolism, Pfizer Inc. , Groton, Connecticut 06340, United States.
authors.forename: Wei
authors.initials: W
authors.lastname: Song
authors.affiliation: Pharmacokinetics, Dynamics and Metabolism, Pfizer Inc. , Andover, Massachusetts 01810, United States.
authors.forename: James
authors.initials: J
authors.lastname: McNally
authors.affiliation: Pharmacokinetics, Dynamics and Metabolism, Pfizer Inc. , Andover, Massachusetts 01810, United States.
authors.forename: Quazi
authors.initials: Q
authors.lastname: Shakey
authors.affiliation: Pharmacokinetics, Dynamics and Metabolism, Pfizer Inc. , Groton, Connecticut 06340, United States.
authors.forename: Leslie
authors.initials: L
authors.lastname: Lorello
authors.affiliation: Oncology Research Unit, Pfizer Inc. , Pearl River, New York 10965, United States.
authors.forename: Judy
authors.initials: J
authors.lastname: Lucas
authors.affiliation: Oncology Research Unit, Pfizer Inc. , Pearl River, New York 10965, United States.
authors.forename: Puja
authors.initials: P
authors.lastname: Sapra
mesh_terms: D000818:Animals; D061067:Antibodies, Monoclonal, Humanized / Q000737:chemistry / Q000276:immunology / Q000493:pharmacokinetics*; D045744:Cell Line, Tumor; D005260:Female; D006801:Humans; D018796:Immunoconjugates / Q000737:chemistry / Q000276:immunology / Q000493:pharmacokinetics*; D008252:Macaca fascicularis; D008562:Membrane Glycoproteins / Q000276:immunology*; D051379:Mice; D008819:Mice, Nude; D009369:Neoplasms / Q000188:drug therapy; D009842:Oligopeptides / Q000737:chemistry / Q000276:immunology / Q000493:pharmacokinetics*; D051381:Rats; D017207:Rats, Sprague-Dawley; D014018:Tissue Distribution
chemical_list: D061067:Antibodies, Monoclonal, Humanized; D018796:Immunoconjugates; D008562:Membrane Glycoproteins; D009842:Oligopeptides; C513576:monomethylauristatin F; C063709:trophoblastic glycoprotein 5T4, human