title: Intravitreal bevacizumab: safety of multiple doses from a single vial for consecutive patients.
abstract: OBJECTIVE
  To report the incidence of endophthalmitis after intravitreal injection of anti-vascular endothelial growth factor and the safety profile of multiple doses of bevacizumab from the same vial reused for multiple patients.
  
  
  METHODS
  Case series.
  
  
  METHODS
  A private hospital in Hong Kong.
  
  
  METHODS
  A systematic retrospective review of consecutive intravitreal anti-vascular endothelial growth factor injections between 5 June 2006 and 17 December 2010 at a single institute was conducted. Patients were identified from prospectively designed audit forms, and each patient's medical record was reviewed for any documented complications. Bevacizumab 1.25 mg/0.05 mL to 2.50 mg/0.1 mL was aspirated from the designated vial, with a maximum of 10 consecutive injections being aspirated from the same vial. The opened vial was then discarded without overnight storage. Ranibizumab was aspirated from the commercially available 1 mg/0.1 mL single-use vial.
  
  
  RESULTS
  A total of 1655 intravitreal anti-vascular endothelial growth factor injections into 392 eyes of 383 patients were evaluated during the study period. There were 1184 bevacizumab injections and 471 ranibizumab injections. There was one case of suspected endophthalmitis after ranibizumab injection, though culture of the vitreous tap was negative. The point prevalence of endophthalmitis was 0.06% (1/1655) for the total number of injections: 0.21% (1/471) after ranibizumab, and 0% after bevacizumab.
  
  
  CONCLUSIONS
  Although many centres aliquot multiple syringes from a single vial to be kept in a refrigerator for use, the current study shows that so long as proper sterile techniques are implemented, there were no cases of endophthalmitis from using the same vial, which was reused for a maximum of 10 consecutive injections. For intravitreal injection, bevacizumab costs approximately US$50 to US$100 per dose, as opposed to US$2000 per dose for ranibizumab. Sharing multiple doses of bevacizumab from a single vial can substantially reduce the cost of treatment.
authors.affiliation: Department of Ophthalmology, Tung Wah Eastern Hospital, Sheung Wan, Hong Kong.
authors.forename: Danny S
authors.initials: DS
authors.lastname: Ng
authors.forename: Alvin K H
authors.initials: AK
authors.lastname: Kwok
authors.forename: Clement W
authors.initials: CW
authors.lastname: Chan
authors.forename: Walton W T
authors.initials: WW
authors.lastname: Li
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D020533:Angiogenesis Inhibitors / Q000008:administration & dosage / Q000009:adverse effects* / Q000191:economics; D061067:Antibodies, Monoclonal, Humanized / Q000008:administration & dosage / Q000009:adverse effects* / Q000191:economics; D000068258:Bevacizumab; D004209:Disposable Equipment; D004340:Drug Contamination; D016527:Drug Costs; D004349:Drug Packaging; D004356:Drug Storage; D009877:Endophthalmitis / Q000139:chemically induced / Q000453:epidemiology*; D005260:Female; D006723:Hong Kong; D016304:Hospitals, Private; D006801:Humans; D015994:Incidence; D058449:Intravitreal Injections; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D000069579:Ranibizumab; D012189:Retrospective Studies; D042461:Vascular Endothelial Growth Factor A / Q000037:antagonists & inhibitors
chemical_list: D020533:Angiogenesis Inhibitors; D061067:Antibodies, Monoclonal, Humanized; D042461:Vascular Endothelial Growth Factor A; D000068258:Bevacizumab; D000069579:Ranibizumab