Effect of Sch 55700, a humanized monoclonal antibody to human interleukin-5, on eosinophilic responses and bronchial hyperreactivity

Arzneimittelforschung. 1999 Sep;49(9):779-90. doi: 10.1055/s-0031-1300502.


This report describes the development and the biology of Sch 55700, a humanized monoclonal antibody to human IL-5 (hIL-5). Sch 55700 was synthesized using CDR (complementarity determining regions) grafting technology by incorporating the antigen recognition sites for hIL-5 onto consensus regions of a human IgG4 framework. In vitro, Sch 55700 displays high affinity (Kd = 20 pmol/l) binding to hIL-5, inhibits the binding of hIL-5 to Ba/F3 cells (IC50 = 0.5 nmol/l) and blocks IL-5 mediated proliferation of human erythroleukemic TF-1 cells. In allergic mice, Sch 55700 (0.1-10 mg/kg, i.p. or i.m.) inhibits the influx of eosinophils in the lungs, demonstrates long duration of activity and the anti-inflammatory activity of this compound is additive with oral prednisolone. In allergic guinea pigs, Sch 55700 (0.03-30 mg/kg i.p.) inhibits both the pulmonary eosinophilia and airway hyperresponsiveness and at 30 mg/kg, i.p. inhibited allergic, but not histamine-induced bronchoconstriction. In allergic rabbits, Sch 55700 blocks cutaneous eosinophilia. Sch 55700 (0.1-1 mg/kg i.p.) also blocks the pulmonary eosinophilia and neutrophilia caused by tracheal injection of hIL-5 in guinea pigs. In allergic cynomolgus monkeys, a single dose of Sch 55700 (0.3 mg/kg i.v.) blocks the pulmonary eosinophilia caused by antigen challenge for up to six months. Sch 55700 is, therefore, a potent antibody against IL-5 in vitro and in a variety of species in vivo that could be used to establish the role of IL-5 in human eosinophilic diseases such as asthma.

MeSH terms

  • Animals
  • Antibodies, Monoclonal / biosynthesis
  • Antibodies, Monoclonal / pharmacology*
  • Binding, Competitive
  • Bronchial Hyperreactivity / immunology
  • Bronchial Hyperreactivity / pathology*
  • Cell Division / drug effects
  • Cell Line
  • Cloning, Molecular
  • Eosinophilia / immunology
  • Eosinophilia / pathology
  • Eosinophils / drug effects*
  • Eosinophils / immunology
  • Eosinophils / pathology
  • Humans
  • Immunoglobulin G / immunology
  • Interleukin-5 / immunology*
  • Interleukin-5 / metabolism
  • Kinetics
  • Leukocyte Count
  • Lung / immunology
  • Lung / pathology
  • Macaca fascicularis
  • Mice
  • Mice, Inbred Strains
  • Neutrophils / pathology
  • Rabbits
  • Rats
  • Skin / immunology
  • Skin / pathology


  • Antibodies, Monoclonal
  • Immunoglobulin G
  • Interleukin-5