title: "Treat and extend" dosing of intravitreal antivascular endothelial growth factor therapy for type 3 neovascularization/retinal angiomatous proliferation.
abstract: OBJECTIVE
  The purpose of this study was to analyze long-term outcomes for the treatment of type 3 neovascularization/retinal angiomatous proliferation using a "Treat and Extend" dosing regimen for antivascular endothelial growth factor therapy.
  
  
  METHODS
  This was a retrospective analysis of visual acuity and optical coherence tomography data of 11 eyes of 10 consecutive patients with newly diagnosed type 3 neovascularization/retinal angiomatous proliferation treated with intravitreal bevacizumab and/or ranibizumab with at least a 12-month follow-up. Three monthly injections were followed by continued treatment at intervals increasing by 2 weeks per visit, to a maximum of 10 weeks, unless clinical or optical coherence tomography evidence of persistent or recurrent fluid was present, in which case, the interval was shortened.
  
  
  RESULTS
  Mean baseline Snellen visual acuity was 20/80, improved to 20/40 at 1 month, and was maintained throughout the 36-month period (n = 11 at 12 months, n = 10 at 24 months, and n = 8 at 36 months) (P < 0.04, paired t-test). The mean center point optical coherence tomography thickness decreased from 320 microm to 180-230 microm, and was maintained during the study period (P < 0.02). The mean number of injections was seven in the first year, six in the second year, and seven in the third year.
  
  
  CONCLUSIONS
  "Treat and Extend" antivascular endothelial growth factor dosing in type 3 neovascularization/retinal angiomatous proliferation delivers promising outcomes at a reduced burden for the patient and health care system compared with monthly and optical coherence tomography-guided dosing regimens.
authors.affiliation: LuEsther T Mertz Retinal Research Center, Manhattan Eye, Ear and Throat Hospital, New York, NY, USA.
authors.forename: Michael
authors.initials: M
authors.lastname: Engelbert
authors.forename: Sandrine A
authors.initials: SA
authors.lastname: Zweifel
authors.forename: K Bailey
authors.initials: KB
authors.lastname: Freund
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D020533:Angiogenesis Inhibitors / Q000008:administration & dosage*; D000911:Antibodies, Monoclonal / Q000008:administration & dosage; D061067:Antibodies, Monoclonal, Humanized; D000068258:Bevacizumab; D020256:Choroidal Neovascularization / Q000175:diagnosis / Q000188:drug therapy* / Q000503:physiopathology; D005260:Female; D005451:Fluorescein Angiography; D006801:Humans; D007267:Injections; D008268:Macular Degeneration / Q000175:diagnosis / Q000188:drug therapy* / Q000503:physiopathology; D008297:Male; D000069579:Ranibizumab; D015861:Retinal Neovascularization / Q000175:diagnosis / Q000188:drug therapy* / Q000503:physiopathology; D012189:Retrospective Studies; D041623:Tomography, Optical Coherence; D016896:Treatment Outcome; D042461:Vascular Endothelial Growth Factor A / Q000037:antagonists & inhibitors*; D014792:Visual Acuity / Q000502:physiology; D014822:Vitreous Body
chemical_list: D020533:Angiogenesis Inhibitors; D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D042461:Vascular Endothelial Growth Factor A; D000068258:Bevacizumab; D000069579:Ranibizumab