title: High-molecular-weight aggregates in repackaged bevacizumab.
abstract: OBJECTIVE
  The antivascular endothelial growth factor agents ranibizumab and bevacizumab are used to treat ocular neovascular diseases. There have been recent reports of sustained elevation of intraocular pressure after use of either agent, which we hypothesize could be because of high-molecular-weight aggregates.
  
  
  METHODS
  Enzyme-linked immunosorbent assay, size exclusion chromatography, and polyacrylamide gel electrophoresis were used to analyze repackaged bevacizumab syringes obtained from three outside compounding pharmacies and samples obtained directly from the original vial. Microflow imaging was used to examine particulate material within samples.
  
  
  RESULTS
  All syringes contained statistically similar amounts of protein, consisting of immunoglobulin (IgG) heavy and light chains (polyacrylamide gel electrophoresis). However, two of the three compounding pharmacies' batches had significantly less functional IgG in the solution (enzyme-linked immunosorbent assay). Additionally, the compounding pharmacies with the lowest IgG ( approximately 50%) also contained 10-fold the number of micron-sized particulate matter as measured by microflow imaging.
  
  
  CONCLUSIONS
  There are significant differences in IgG concentration measured from repackaged bevacizumab syringes. A trend exists for an increase in micron-sized protein aggregates with the decrease in IgG concentration. Large particulate matter within some samples may lead to obstruction of aqueous outflow and subsequent elevation in intraocular pressure. Additional studies are warranted to explore these findings.
authors.affiliation: Department of Ophthalmology, Rocky Mountain Lions Eye Institute, University of Colorado Denver, Aurora, Colorado 80045, USA. malik.kahook@gmail.com
authors.forename: Malik Y
authors.initials: MY
authors.lastname: Kahook
authors.forename: Lu
authors.initials: L
authors.lastname: Liu
authors.forename: Philip
authors.initials: P
authors.lastname: Ruzycki
authors.forename: Naresh
authors.initials: N
authors.lastname: Mandava
authors.forename: John F
authors.initials: JF
authors.lastname: Carpenter
authors.forename: J Mark
authors.initials: JM
authors.lastname: Petrash
authors.forename: David A
authors.initials: DA
authors.lastname: Ammar
mesh_terms: D020533:Angiogenesis Inhibitors / Q000737:chemistry*; D000911:Antibodies, Monoclonal / Q000737:chemistry*; D061067:Antibodies, Monoclonal, Humanized; D000068258:Bevacizumab; D002850:Chromatography, Gel; D004349:Drug Packaging; D004591:Electrophoresis, Polyacrylamide Gel; D004797:Enzyme-Linked Immunosorbent Assay; D007143:Immunoglobulin Heavy Chains / Q000032:analysis; D007147:Immunoglobulin Light Chains / Q000032:analysis; D046210:Microfluidic Analytical Techniques; D008970:Molecular Weight; D052638:Particulate Matter; D042461:Vascular Endothelial Growth Factor A / Q000037:antagonists & inhibitors*
chemical_list: D020533:Angiogenesis Inhibitors; D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D007143:Immunoglobulin Heavy Chains; D007147:Immunoglobulin Light Chains; D052638:Particulate Matter; D042461:Vascular Endothelial Growth Factor A; D000068258:Bevacizumab