Simultaneous Dexamethasone Intravitreal Implant and Anti-VEGF Therapy for Neovascular Age-Related Macular Degeneration Resistant to Anti-VEGF Monotherapy

Abstract

Purpose:

To evaluate the efficacy of a dexamethasone intravitreal implant in combination with intravitreal anti-vascular endothelial growth factor (VEGF) agents for treatment-resistant neovascular age-related macular degeneration (nvAMD).

Methods:

This study was designed as a single-center, retrospective interventional case series. Consecutive patients with treatment-resistant nvAMD underwent simultaneous combined injection of anti-VEGF agent and dexamethasone intravitreal implant. Eighteen patients with mean age of 81.5 years were included. Patients received an average of 26.3 anti-VEGF injections before dual therapy, with a mean follow-up of 8.2 months after dual therapy.

Results:

Dual therapy produced a significant mean decrease in central foveal thickness (126.3 μm), compared to a mean increase in 29.9 μm when treated with anti-VEGF monotherapy (P = .0017). Patients also had a mean decrease in macular cube volume of −0.85 mm³ with dual therapy compared to anti-VEGF monotherapy (P = .0014). There was a moderate correlation between the number of prior anti-VEGF injections and the magnitude of anatomic response, suggesting that shorter disease duration may positively influence response to combined treatment. Although there was a slight trend toward improved mean visual acuity after dual therapy, these differences did not reach statistical significance. Nevertheless, with combination treatment, 33% of patients gained 1 or more lines of vision. Dual therapy resulted in a significantly lower number of required anti-VEGF injections (4.25 vs 5.33) and an increase in the anti-VEGF injection-free interval to 1.41 months from 1.12 months during the 6 months following dual therapy compared to the same interval before dual therapy. Dual therapy was well tolerated; 2 eyes developed mild intraocular pressure elevation effectively managed with topical therapy and 1 patient developed worsening cataract.

Conclusions:

Combined treatment of anti-VEGF with dexamethasone intravitreal implant is a viable alternative for treatment-resistant nvAMD and may reduce treatment burden. Earlier treatment with dual therapy may be beneficial to maximize anatomic and visual outcomes in these patients.