Prospective study evaluating the predictability of need for retreatment with intravitreal ranibizumab for age-related macular degeneration

Graefes Arch Clin Exp Ophthalmol. 2013 Mar;251(3):697-704. doi: 10.1007/s00417-012-2090-9. Epub 2012 Jun 26.


Purpose: To investigate the rhythm and predictability of the need for retreatment with intravitreal injections of ranibizumab for neovascular age-related macular degeneration (nAMD).

Methods: This prospective study enrolled 39 patients with treatment-naïve nAMD. After three loading doses of intravitreal ranibizumab, patients underwent an intensified follow-up for 12 months (initially weekly, then with stepwise increases to every 2 weeks and to monthly after each injection). Patients were retreated on an as-needed basis if any fluid or increased central retinal thickness (CRT) (>50 μm) was found on spectral domain optical coherence tomography (OCT). Statistical analysis included patients who received at least two retreatments (five injections).

Results: A mean of 7.5 injections (range 0-12) were given between months 3 and 15. The mean visual acuity increased by 13.1 and 12.6 ETDRS letters at months 12 and 15 respectively. Two or more injection-retreatment intervals were found in 31 patients. The variability of their intra-individual intervals up to 14 weeks was small (SD 0-2.13 weeks), revealing a high regularity of the retreatment rhythm. The SD was correlated with the mean interval duration (r = 0.89, p < 0.001). The first interval was a good predictor of the following intervals (regression coefficient =0.81). One retreatment criterion was stable in 97 % of patients (cysts or subretinal fluid).

Conclusion: The results of this study demonstrate a high intra-individual predictability of retreatment need with ranibizumab injections for nAMD. These findings may be helpful for developing individualized treatment plans for maintained suppression of disease activity with a minimum of injections and visits.

MeSH terms

  • Aged
  • Aged, 80 and over
  • Angiogenesis Inhibitors / therapeutic use*
  • Antibodies, Monoclonal, Humanized / therapeutic use*
  • Female
  • Fluorescein Angiography
  • Follow-Up Studies
  • Humans
  • Intravitreal Injections
  • Male
  • Middle Aged
  • Prospective Studies
  • Ranibizumab
  • Retreatment
  • Tomography, Optical Coherence
  • Vascular Endothelial Growth Factor A / antagonists & inhibitors
  • Visual Acuity
  • Wet Macular Degeneration / diagnosis*
  • Wet Macular Degeneration / drug therapy*


  • Angiogenesis Inhibitors
  • Antibodies, Monoclonal, Humanized
  • VEGFA protein, human
  • Vascular Endothelial Growth Factor A
  • Ranibizumab