Certain neovascular AMD patients may benefit from second-line aflibercept therapy
Neovascular age-related macular degeneration (nvAMD) patients with inadequate response to initial bevacizumab therapy may benefit from an early switch to aflibercept therapy, which has been demonstrated to improve best corrected visual acuity (BCVA) and reduce central subfield thickness (CST).
In the Aflibercept as a Second Line Therapy for Neovascular Age Related Macular Degeneration in Israel (ASLI), three monthly intravitreal aflibercept 2 mg injections were administered, followed by two bimonthly injections and a final examination at week 28 (with an optional injection allowed at week 20) to 47 eyes of 46 patients (mean age 76 years). All eyes had incomplete response to between three and nine prior bevacizumab injections (mean, 5.5).
At week 28, the mean visual acuity improved from 60.3 Early Treatment Diabetic Retinopathy Study letters at baseline to 63.1 letters (p=0.02). Moreover, the CST decreased from 409 microns at baseline to 330 microns at week 4 (p=0.0002) and 277 microns at week 28 (p=0.00002).
Prior bevacizumab injections ranged between three and five in 22 eyes (mean, 5.1 injections) and between six and nine in 25 eyes (mean, 7.32±1.2). CST decreased from baseline in both groups at week 28 (p=0.0004 and p=0.0007, respectively). More than half of the eyes (75 percent) required the optional additional aflibercept injection at week 20.
Antivascular endothelial growth factor (VEGF) compounds, administered intravitreally, have been shown to have favourable effect on the short- and intermediate-term outcome of nvAMD. Compared with bevacizumab and ranibizumab, aflibercept has higher binding affinity for VEGF-A by binding to placental growth factors 1 and 2 and VEGF-B, researchers noted.
In addition, aflibercept has a longer half-life in the vitreous as compared with ranibizumab. [Angiogenesis 2012;15:171–185; Invest Ophthalmol Vis Sci 2003;44:3186–3193]
The present data suggest that aflibercept improves anatomical and visual outcome in nvAMD eyes with incomplete response to first-line bevacizumab therapy.
“Majority of eyes required monthly second-line aflibercept therapy during the first 6 months to preserve a fluid-free macula,” researchers said. “Magnitude of anatomical and visual response may be similar regardless whether second-line therapy is commenced after few months of first-line therapy or later. Yet, final outcome may depend on the initial visual acuity.”