A recent study published in BMJ Open Ophthalmology sought to evaluate the long-term effects of anti-vascular endothelial growth factor (anti-VEGF) therapy for the treatment of neovascular age-related macular degeneration (nAMD).
Give me some background first.
Pro re nata (PRN) and treat and extend (T&E) regimens in anti-VEGF therapy were developed as more flexible regimens for treating nAMD.
The goal: to decrease potentially unnecessary injections and clinic visits—a major distinction from fixed monthly and bimonthly injection methods.
While previous randomized controlled trials (RCTs) have displayed a short-term efficacy for nAMD, the long-term effects have yet to be explored.
Now talk about the study.
The retrospective study evaluated 10 years of anti-VEGF intravitreal injections (IVIs) that used a PRN treatment regimen.
Data was collected from 3,844 treatment-naïve eyes (of 3,008 nAMD patients) with a total of 50,146 IVIs (87% bevacizumab) administered dating from 2008-2020. Further, the median baseline age was 80 years old.
What was being measured?
Outcome measures included:
- Mean change in visual acuity (VA) from baseline
- Proportion of eyes gaining ≥5 letters
- Proportion of eyes with stable vision (within 15 letters of baseline)
- VA ≥20/40 (Snellen) and VA ≤20/200 (Snellen)
- Number of annual visits
- Number of annual IVIs
Findings?
Outcomes were measured at benchmark years 1, 2, 3, 5, 7, and 10, respectively.The proportions of eyes within 15 letters of baseline were 88%, 87%, 82%, 80%, 76%, and 72%, respectively.
Per the study authors, “The mean baseline VA was 55 Early Treatment Diabetic Retinopathy Study (ETDRS) letters and the mean change in VA from baseline was +2, +2, ±0, –2, −2, and −4 ETDRS letters at year 1, 2, 3, 5, 7 and 10, respectively.”
What about the annual number of IVIs and visits?
Annual intravitreal injections had a median of 6 at years 1 through 7 and a median of 5 at year 10. The median of total annual visits was:
- 10 at Year 1
- 9 at Years 2 to 7
- 8 at Year 10
VA was shown to be maintained up to 10 years, with a median of 6 annual IVIs and 3 to 4 annual non-injection visits.
Any limitations?
The study authors noted, given the real-world setting, high drop-out rates and patient selection bias with longer follow-up times.
Further, only a small percentage (8%) of participants completed the study follow-up.
See the complete list here.
Expert opinion?
The authors stated that, “VA gains were most beneficial in eyes with lower baseline VA and mean VA was maintained long-term with PRN regimen if patient adherence was sufficient."
However, they advised that further research is needed to investigate optimal real-world treatment regimens for international comparability and personalized patient care.
Take home.
The use of anti-VEGF therapy to treat nAMD may benefit VA maintenance in the long-term—in addition to short-term using PRN regimen—particularly in a real-world setting.