Pharmacokinetics of intravitreal ranibizumab (Lucentis)

Ophthalmology. 2007 Dec;114(12):2179-82. doi: 10.1016/j.ophtha.2007.09.012.

Abstract

Purpose: To describe the pharmacokinetics of 0.5 mg of intravitreal ranibizumab (Lucentis) and to compare it with that of 1.25 mg of intravitreal bevacizumab (Avastin), using the same rabbit model.

Design: Experimental animal study.

Participants: Twenty-eight Dutch-belted rabbits.

Methods: One eye of each of 20 rabbits was injected with 0.5 mg of intravitreal ranibizumab. Both eyes of each of 4 rabbits were enucleated at days 1, 3, 8, 15, and 29. Ranibizumab concentrations were measured in aqueous fluid, whole vitreous, and serum. A further 8 rabbits were used to measure serum and fellow ranibizumab at additional time points of 3 and 8 hours.

Main outcome measures: Ranibizumab concentrations in the aqueous, vitreous, and serum.

Results: Although vitreous concentrations of ranibizumab declined in a monoexponential fashion with a half-life of 2.88 days, concentrations of >0.1 microg/ml ranibizumab were maintained in the vitreous humor for 29 days. Ranibizumab concentrations in the aqueous humor of the injected eye reached a peak concentration of 17.9 microg/ml, 3 days after drug administration. Elimination of ranibizumab from the aqueous humor paralleled that found in the vitreous humor, with a half-life value of 2.84 days. No ranibizumab was detected in the serum or the fellow eye.

Conclusion: In the rabbit, the vitreous half-life of 0.5-mg intravitreal ranibizumab is 2.88 days, shorter than the half-life of 1.25-mg intravitreal bevacizumab of 4.32 days. No ranibizumab was detected in the serum or the fellow uninjected eye; whereas small amounts of intravitreal bevacizumab have been detected in the serum and fellow uninjected eye.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Angiogenesis Inhibitors / pharmacokinetics*
  • Animals
  • Antibodies, Monoclonal / pharmacokinetics*
  • Antibodies, Monoclonal, Humanized
  • Aqueous Humor / metabolism*
  • Bevacizumab
  • Biological Availability
  • Half-Life
  • Male
  • Rabbits
  • Ranibizumab
  • Tissue Distribution
  • Vascular Endothelial Growth Factor A / antagonists & inhibitors
  • Vitreous Body / metabolism*

Substances

  • Angiogenesis Inhibitors
  • Antibodies, Monoclonal
  • Antibodies, Monoclonal, Humanized
  • VEGFA protein, human
  • Vascular Endothelial Growth Factor A
  • Bevacizumab
  • Ranibizumab