title: Theory based analysis of anti-inflammatory effect of infliximab on Crohn's disease.
abstract: Tumor necrosis factor (TNF)-alpha, a primary mediator of inflammatory responses, is increased in patients with active Crohn's disease (CD) and considered to play an important role in the regulation of inflammation in CD. Infliximab (IFX) is a chimeric murine-human monoclonal IgG1 antibody that targets TNF-alpha and is used as a therapeutic agent for CD. Although that dosage regimen has been established through clinical trial experience, it has not been analyzed theoretically. We analyzed of sequential changes of the Crohn's disease activity index (CDAI) using a pharmacokinetic-pharmacodynamic model integrating the pharmacokinetics of IFX and turnover rate of TNF-alpha. The time course effects of IFX derived from the present model were matched to reported data regarding CDAI ratios, and we found that the clinical effect of IFX reached a maximum value 2 to 4 weeks after administration and was maintained for the next several weeks. Our results suggested that the standard dosage regimen of IFX is theoretically appropriate. Further, based on the results of various dosage regimens, a second administration of IFX 2 weeks after the first dose was shown to achieve remission in the early stage of active CD, when IFX was given as a repeated treatment.
authors.affiliation: Department of Clinical Evaluation of Drug Efficacy, School of Pharmacy, Tokyo University of Pharmacy and Life Science, Japan.
authors.forename: Yoko
authors.initials: Y
authors.lastname: Furuya
authors.forename: Takeshi
authors.initials: T
authors.lastname: Ozeki
authors.forename: Risa
authors.initials: R
authors.lastname: Takayanagi
authors.forename: Haruko
authors.initials: H
authors.lastname: Yokoyama
authors.forename: Kiyoshi
authors.initials: K
authors.lastname: Okuyama
authors.forename: Yasuhiko
authors.initials: Y
authors.lastname: Yamada
mesh_terms: D000465:Algorithms; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000008:administration & dosage / Q000493:pharmacokinetics / Q000627:therapeutic use*; D000911:Antibodies, Monoclonal / Q000008:administration & dosage / Q000493:pharmacokinetics / Q000627:therapeutic use*; D003424:Crohn Disease / Q000188:drug therapy* / Q000473:pathology; D006801:Humans; D000069285:Infliximab; D015233:Models, Statistical; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D000911:Antibodies, Monoclonal; D014409:Tumor Necrosis Factor-alpha; D000069285:Infliximab