Diabetic Macular Edema Treated with Intravitreal Aflibercept Injection After Treatment with Other Anti-VEGF Agents (SWAP-TWO Study) – 12-month interim analysis

Abstract

Purpose : Anti-vascular endothelial growth factor (VEGF) agents have become first-line treatment for diabetic macular edema (DME). There is a lack of well-designed, prospective, clinical trials that have evaluated the effect of switching anti-VEGF agents on DME outcomes. The purpose of this prospective study is to report the 12-month outcomes of patients with DME previously treated with other anti-VEGF agents who are transitioned to intravitreal aflibercept (IAI) on a fixed dosing regimen.

Methods : This prospective study included 20 patients presenting with DME who were previously treated with ranibizumab or bevacizumab. Initially, all patients were treated with IAI 2 mg (0.05 mL) every 4 weeks until optical coherence tomography (OCT) demonstrated no evidence of fluid (defined as lack of subretinal fluid; central subfield thickness (CST) of less than 320 µm; extrafoveal cystoid macular edema (CME); or foveal CME with foveal depression present or with fovea flat). Patients then received a fixed dosing schedule of IAI 2 mg once every 8 weeks through 24 months with a planned interim analysis at 12 months. Mean absolute change from baseline CST at 12 months was measured by OCT. Other outcomes analyzed included mean change from baseline in ETDRS visual acuity, anatomic parameters, and OCT angiography (OCTA) capillary perfusion density (CPD) in the superficial and deep capillary layers after transition to IAI therapy.

Results : The mean age of patients was 63.7 (range, 45-78). The average number of injections prior to enrollment was 4.25. At baseline, best corrected visual acuity (BCVA) was 70.0 letters, average CST on OCT was 419.7 µm +/-92.0, and foveal avascular zone (FAZ) area was 0.29 mm³ +/-0.12. Superficial and deep CPD were 46.0% +/-4.2 and 50.8% +/-4.3 at baseline, respectively. At 12-months, BCVA increased by +3.7 (p=0.099). Average CST on OCT improved to 287.2 µm +/-80.2 (p<0.001). FAZ area increased to 0.33 mm³ +/-0.15 (p=0.10). Superficial CPD decreased to 43.6 % +/-4.8 (p=0.040) and deep CPD decreased to 47.6 % +/-4.8 (p=0.049).

Conclusions : Patients previously undergoing anti-VEGF therapy with ranibizumab or bevacizumab who were transitioned to a fixed dosing regimen of IAI demonstrated significant continued anatomic improvements in CST through 12 months. CPD values decreased significantly in both superficial and deep layers.

This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.