title: Switching from pro re nata to treat-and-extend regimen improves visual acuity in patients with neovascular age-related macular degeneration.
abstract: OBJECTIVE
  To evaluate the visual outcome after transitioning from a pro re nata (PRN) intravitreal injection regimen to a treat-and-extend (TAE) regimen for patients with neovascular age-related macular degeneration (AMD).
  
  
  METHODS
  A retrospective review of patients who were switched from a PRN regimen with intravitreal injections of bevacizumab, ranibizumab or aflibercept to a TAE regimen. The best corrected visual acuity (BCVA), central retinal thickness (CRT) and type of medication used at baseline, at the time of changing treatment regimen and at the end of the study were analysed.
  
  
  RESULTS
  Twenty-one eyes of 21 patients met the inclusion criteria. Prior to the switch, the patients received a mean of 13.8 injections (median, 10; range, 3-39 injections) with the PRN regimen for 44 months (range, 3-100 months), which improved the visual acuity in five patients (24%). After a mean of 6.1 injections (median, 5; range, 3-14 injections) with the TAE regimen over 8 months (range, 2-16 months), the visual acuity improved in 12 patients (57%). The improvement in visual acuity during treatment with the TAE regimen was statistically significant (p = 0.005). The proportion of patients with a visual acuity of 0.2 or better was significantly higher after treatment with the TAE regimen than after treatment with the PRN regimen (p = 0.048). No significant differences in CRT were found between the two treatment regimens.
  
  
  CONCLUSIONS
  Even after prolonged treatment and a high number of intravitreal injections, switching AMD patients from a PRN regimen to a strict TAE regimen significantly improves visual acuity.
authors.affiliation: Department of Ophthalmology, Haukeland University Hospital, Bergen, Norway.|Department of Ophthalmology, Division Lillehammer, Innlandet Hospital Trust, Lillehammer, Norway.
authors.forename: Line
authors.initials: L
authors.lastname: Kvannli
authors.affiliation: Department of Ophthalmology, Haukeland University Hospital, Bergen, Norway.|Department of Clinical Medicine, Section of Ophthalmology, University of Bergen, Bergen, Norway.
authors.forename: Jørgen
authors.initials: J
authors.lastname: Krohn
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D020533:Angiogenesis Inhibitors / Q000008:administration & dosage; D000068258:Bevacizumab / Q000008:administration & dosage*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D058449:Intravitreal Injections; D008297:Male; D008875:Middle Aged; D000069579:Ranibizumab / Q000008:administration & dosage*; D040262:Receptors, Vascular Endothelial Growth Factor / Q000008:administration & dosage*; D011993:Recombinant Fusion Proteins / Q000008:administration & dosage*; D012160:Retina / Q000473:pathology*; D012189:Retrospective Studies; D013997:Time Factors; D041623:Tomography, Optical Coherence; D016896:Treatment Outcome; D042461:Vascular Endothelial Growth Factor A / Q000037:antagonists & inhibitors; D014792:Visual Acuity; D057135:Wet Macular Degeneration / Q000175:diagnosis / Q000188:drug therapy* / Q000503:physiopathology
chemical_list: D020533:Angiogenesis Inhibitors; D011993:Recombinant Fusion Proteins; D042461:Vascular Endothelial Growth Factor A; C533178:aflibercept; D000068258:Bevacizumab; D040262:Receptors, Vascular Endothelial Growth Factor; D000069579:Ranibizumab
keywords: age-related macular degeneration; anti-VEGF therapy; pro re nata; treat-and-extend; treat-and-observe