Glycosylated and non-glycosylated recombinant human granulocyte colony-stimulating factor (rhG-CSF)--what is the difference?

Med Oncol. 1998 Dec;15(4):229-33. doi: 10.1007/BF02787205.

Abstract

Two forms of recombinant human G-CSF (rhG-CSF) are available for clinical use: filgrastim is expressed in E coli and non-glycosylated, whereas lenograstim is derived from Chinese hamster ovary (CHO) cells and glycosylated. The function of the sugar chain, accounting for approximately 4% of the molecular weight of lenograstim (and native G-CSF), is not known. Glycosylation of the G-CSF molecule does not prolong its circulation half life. Lenograstim is more active than filgrastim (and research-use deglycosylated G-CSF) on a weight-by-weight basis in in vitro colony-forming and cell line assays. An international potency standard assigns a specific activity of 100,000 IU/microgram to filgrastim and 127,760 IU/microgram to lenograstim. Correspondingly, two randomised crossover studies in normal subjects, comparing mass equivalent doses of the two rhG-CSFs, have demonstrated a 25-30% higher concentration of blood stem cells (CD34+, CFU-GM) during lenograstim administration. No difference in side effects was observed. Results from a prospective, randomised, non-crossover trial in breast cancer patients suggest that bioequivalent doses of filgrastim and lenograstim have a similar effect on mobilisation of CD34+ cells and immature CD34+ cell subsets, respectively. Although comparisons outside the setting of stem cell mobilisation are lacking, the clinical relevance of the greater specific activity of lenograstim may thus be limited. The difference in potency between microgram identical doses of the two rhG-CSFs makes dosing in biological units (IU) rather than mass units (microgram) more appropriate.

Publication types

  • Comparative Study
  • Review

MeSH terms

  • Adjuvants, Immunologic / administration & dosage*
  • Adjuvants, Immunologic / adverse effects
  • Adjuvants, Immunologic / chemistry
  • Animals
  • Controlled Clinical Trials as Topic
  • Female
  • Filgrastim
  • Glycosylation
  • Granulocyte Colony-Stimulating Factor / administration & dosage*
  • Granulocyte Colony-Stimulating Factor / adverse effects
  • Granulocyte Colony-Stimulating Factor / chemistry
  • Humans
  • In Vitro Techniques
  • Lenograstim
  • Male
  • Neoplasms / drug therapy*
  • Randomized Controlled Trials as Topic
  • Recombinant Proteins / administration & dosage
  • Recombinant Proteins / adverse effects
  • Recombinant Proteins / chemistry

Substances

  • Adjuvants, Immunologic
  • Recombinant Proteins
  • Granulocyte Colony-Stimulating Factor
  • Lenograstim
  • Filgrastim