The VEGF treatment of AMD switch study (The vTAS study)

Purpose: To evaluate the effect of aflibercept on anatomic and visual outcomes in patients with choroidal neovascularization (CNV) previously treated with intravitreal ranibizumab with persistent fluid on optical coherence tomography (OCT).

Design: Prospective, open-label study.

Methods: Eighteen patients (19 eyes) with CNV being treated with monthly ranibizumab, with persistent fluid on OCT, were switched to intravitreal aflibercept injections at intervals of up to 8 weeks. The primary outcome was the proportion of patients maintaining vision [<5 letter loss in visual acuity (VA)] at week 48. Secondary outcomes included the change in VA and central macular thickness (CMT) and the frequency of treatment necessary along with the safety of intravitreal aflibercept.

Results: Forty-eight weeks after switching to aflibercept, 16/19 eyes had maintained VA. There was a median increase in vision of 5 letters [interquartile range (IQR): 0, 15; P = 0.06)] and median CMT was reduced from 313 µm (IQR: 214, 334) to 258 µm (IQR: 200, 299; P = 0.02). After stratification by fluid location the reduction in CMT was statistically significant for eyes with intraretinal fluid (IRF) at baseline [median change, -25 µm (IQR: -14, -64); P = 0.01]. Macular volume within 6 mm of the fovea (CMTVol) was significantly reduced in eyes with subretinal fluid (SRF) [-0.20 mm³ (IQR: -1.45, -0.05); P = 0.03].

Conclusions: In this small cohort of eyes, switching to aflibercept seemed beneficial. The majority maintained or improved vision and eyes with IRF or SRF had significant reductions in macular edema. However, visual improvement was not always indicative of anatomical improvement.