Rheumatoid Arthritis: Davis HM

Mascelli MA, Zhou H, Sweet R, Getsy J, Davis HM, Graham M, Abernethy D. · Centocor R and D, 200 Great Valley Parkway, Malvern, PA 19355, USA. · J Clin Pharmacol. · Pubmed #17379759 No free full text.

Abstract: Currently, 14 intact, unconjugated, monoclonal antibodies (Mabs) are approved for therapeutic use in the United States, and more than 100 Mabs are presently undergoing clinical development or regulatory review. Mabs are large molecular weight glycoproteins that embody structural, biochemical, and pharmacologic properties distinct from other biologics or chemically synthesized compounds. Early therapeutic Mabs were murine proteins, and clinical testing of these agents revealed serious immune-mediated toxicities. The side effect profile of murine Mab therapeutic agents restricted the clinical development of these agents to indications with high morbidity and/or mortality (ie, oncology, graft vs host rejection). Advances in genetic engineering and protein expression technologies resulted in the development of Mabs composed either predominately (ie, mouse/human chimeric, "humanized") or completely (ie, "fully human" Mabs) of the human amino acid sequence. The production of chimeric, humanized, and fully human Mabs significantly reduced the immune-mediated toxicities and expanded the utility for these agents in numerous therapeutic areas, particularly in chronic disorders requiring either long-term administration (ie, rheumatoid arthritis) or treatment upon the flare up of disease (Crohn's disease, psoriasis). This review provides an overview of the molecular, biochemical, and pharmacokinetic properties and clinical development history of Mabs and details how these factors currently affect the scope and design of early clinical development strategies for these drug candidates. Emphasis is placed on the criteria for selecting appropriate subject populations for phase I testing of Mabs.

Zhou H, Jang H, Fleischmann RM, Bouman-Thio E, Xu Z, Marini JC, Pendley C, Jiao Q, Shankar G, Marciniak SJ, Cohen SB, Rahman MU, Baker D, Mascelli MA, Davis HM, Everitt DE. · Clinical Pharmacology & Experimental Medicine, Centocor Research & Development, 200 Great Valley Parkway, Malvern, PA 19355, USA. · J Clin Pharmacol. · Pubmed #17322150 No free full text.

Abstract: Golimumab is a fully human antitumor necrosis factor alpha (TNF-alpha) monoclonal antibody that is being developed for intravenous and subcutaneous administration. To assess the pharmacokinetics and safety of the intravenous formulation of golimumab, 36 adult subjects with rheumatoid arthritis were randomly assigned to receive a single infusion of placebo or golimumab (0.1, 0.3, 1, 3, 6, or 10 mg/kg). Serum concentrations of golimumab were determined using a validated enzyme-linked immunosorbent assay method. In addition to the noncompartmental analysis and compartmental modeling, a population pharmacokinetics analysis using NONMEM was also conducted. Both the maximum serum concentration and the area under the serum concentrationtime curve appeared to increase in a dose-proportional manner. The median half-life ranged from 7 to 20 days. A 2-compartment population pharmacokinetic model adequately described the pharmacokinetics of golimumab. The following pharmacokinetic parameters (typical value [% coefficient of variation]) were estimated from the population pharmacokinetic model: clearance (CL: 0.40 [10.1%] L/d), volume of distribution in the central compartment (V(c): 3.07 [6.4%] L), intercompartmental clearance (Q: 0.42 [15.5%] L/d), and volume of distribution in the peripheral compartment (V(p): 3.68 [11.8%] L). Interindividual variability of the pharmacokinetic parameters was quantified for CL (44.3%), V(c) (25.5%), Q (44.6%), and V(p) (44.6%). Residual variability was estimated to be 15.0%. Body weight was found to be an important covariate on V(c). Golimumab was generally well tolerated. The pharmacokinetics of golimumab appeared to be linear over the dose range evaluated in this study.

Horninger D, Eirikis E, Pendley C, Giles-Komar J, Davis HM, Miller BE. · Department of Clinical Pharmacology and Experimental Medicine, Centocor, Inc., 145 King of Prussia Road, Radnor, PA 19087, USA. · J Pharm Biomed Anal. · Pubmed #15967298 No free full text.

Abstract: A quantitative, one-step, competitive electrochemiluminescence (ECL)-based immunoassay for the determination of a fully human, anti-TNFalpha monoclonal antibody in human serum has been developed. A biotinylated, mouse anti-variable region-specific antibody and a ruthenium-labeled anti-TNFalpha antibody were the only specific reagents needed to develop the assay. A single incubation step of 2 h followed by ECL detection was used. The assay was capable of measuring the analyte in neat serum over approximately a 1600-fold range with higher concentrations measured following a single dilution. Assay accuracy, precision, and reproducibility were suitable to support pharmacokinetic studies of the analyte. This competitive assay format offers an alternative approach to the development of immunoassays for the measurement of macromolecules in complex matrices to support preclinical and clinical studies.