ANATOMIC AND PHARMACOKINETIC PROPERTIES OF INTRAVITREAL BEVACIZUMAB AND RANIBIZUMAB AFTER VITRECTOMY AND LENSECTOMY

Autor: Michelle M. Williams, Jillian Wang, Michael V. Knopp, George H. Hinkle, Mahmoud Abdel-Rasoul, Angela Jiang, Cedric Pratt, John B. Christoforidis
Rok vydání: 2013
Předmět:
Zdroj: Retina. 33:946-952
ISSN: 0275-004X
DOI: 10.1097/iae.0b013e3182753b12
Popis: To determine the anatomic characteristics and pharmacokinetic properties of intravitreally placed bevacizumab and ranibizumab after pars plana lensectomy or pars plana vitrectomy and to compare these with nonoperated control eyes in a rabbit model.Three groups of six Dutch-belted rabbits each underwent pars plana vitrectomy, pars plana lensectomy, or served as nonsurgical controls. Twelve days after surgery, 3 rabbits from each group underwent intravitreal injection in one eye with 1.25 mg/0.05 mL I-124-bevacizumab or 0.5 mg/0.05 mL I-124-ranibizumab. Serial imaging with integrated positron emission and computed tomography (PET/CT) were obtained on Days 0, 2, 5, 7, 14, 21, 28, and 35. Measured radioactivity emission in becquerels/milliliter was used to calculate the half-lives for each agent.The intravitreally placed radiolabeled agents were contained within the vitreous cavity for the duration of the study. The average clearance half-lives with standard error for bevacizumab and ranibizumab after correction for radioactive decay were, respectively, 4.22 ± 0.07 days and 2.81 ± 0.05 days in unoperated eyes, 2.30 ± 0.09 days (P0.0001) and 2.13 ± 0.05 days (P0.0001) after vitrectomy, and 2.08 ± 0.07 days (P = 0.0001) and 1.79 ± 0.05 days (P0.0001) after lensectomy.Intravitreal retention was longer for bevacizumab than ranibizumab within all study groups and was significantly reduced after vitrectomy and lensectomy for both agents. Consideration for more frequent intravitreal anti-vascular endothelial growth factor dosing regimens may be made for patients whose treated eyes have undergone previous vitrectomy or who are aphakic.
Databáze: OpenAIRE