title: Suppression of intraocular vascular endothelial growth factor during aflibercept treatment of age-related macular degeneration.
abstract: OBJECTIVE
  To determine the duration of suppression of aqueous humor concentrations of vascular endothelial growth factor (VEGF) in eyes with neovascular age-related macular degeneration (AMD) treated with aflibercept.
  
  
  METHODS
  Nonrandomized prospective clinical study.
  
  
  METHODS
  Twenty-seven eyes of 27 neovascular AMD patients receiving intravitreal aflibercept injections on a pro re nata regimen driven by spectral-domain optical coherence tomography (SD OCT) were included in this study. A total of 132 aqueous humor specimens were collected before intravitreal aflibercept injections and their VEGF-A concentrations assayed by multiplex bead analysis.
  
  
  RESULTS
  Mean aqueous humor VEGF concentrations before treatment initiation were 90.6 ± 37.1 pg/mL (range 23.4-190.3 pg/mL). Intravitreal injection of aflibercept suppressed the aqueous VEGF concentrations to below the lower limit of quantification (<4 pg/mL) in all patients. The mean duration of VEGF suppression below the lower limit of quantification was >71 ± 18 days. The earliest time after injection at which the VEGF concentration recovered to above the lower limit of quantification was 55 days in 1 patient and >56 days, the recommended aflibercept treatment interval, in 20 patients. The aqueous VEGF recovery status of 6 patients was uncertain after 56 days.
  
  
  CONCLUSIONS
  On average, VEGF concentrations in the aqueous humor were suppressed below the lower limit of quantification after intravitreal aflibercept injections for about 10 weeks. This aqueous suppression time suggests durable VEGF inhibition for most patients dosed with aflibercept every 8 weeks.
authors.affiliation: Department of Ophthalmology, University Hospital of Cologne, Cologne, Germany.
authors.forename: Sascha
authors.initials: S
authors.lastname: Fauser
authors.affiliation: Department of Ophthalmology, University Hospital of Cologne, Cologne, Germany.
authors.forename: Viktoria
authors.initials: V
authors.lastname: Schwabecker
authors.affiliation: Department of Ophthalmology, University Hospital of Cologne, Cologne, Germany. Electronic address: philmuether@mac.com.
authors.forename: Philipp S
authors.initials: PS
authors.lastname: Muether
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001082:Aqueous Humor / Q000378:metabolism*; D015415:Biomarkers / Q000378:metabolism; D005260:Female; D005451:Fluorescein Angiography; D005500:Follow-Up Studies; D005654:Fundus Oculi; D006801:Humans; D058449:Intravitreal Injections; D008268:Macular Degeneration / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D040262:Receptors, Vascular Endothelial Growth Factor / Q000008:administration & dosage / Q000037:antagonists & inhibitors* / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000008:administration & dosage*; D041623:Tomography, Optical Coherence; D016896:Treatment Outcome; D014792:Visual Acuity
chemical_list: D015415:Biomarkers; D011993:Recombinant Fusion Proteins; C533178:aflibercept; D040262:Receptors, Vascular Endothelial Growth Factor