Aflibercept vs. dexamethasone implant for recalcitrant diabetic macular edema in pseudophakic eyes – 1-year outcomes from a quazi-randomized study in India

Abstract

Purpose: To assess the safety and efficacy of intravitreal Aflibercept (IVA) versus dexamethasone (DEX) implant for treating recalcitrant diabetic macular edema (DME) in pseudophakic eyes at 1-year follow-up. Design: Retrospective comparative case series. Participants: Data of all patients diagnosed with DME between January 2019 and December 2021, who underwent 4-monthly doses of intravitreal ranibizumab but had persistent DME [central macular thickness (CMT) within 10% of baseline value] were extracted from a computerized database. Of these, only pseudophakic eyes that underwent either IVA or DEX implant and had at least 1-year follow-up were included for analysis. Methods: DEX implant was preferred before December 2020 and IVA after this time point. In the IVA group, patients were followed up every month while DEX were followed at least every 3 months. Reinjections were considered when vision dropped by at least 1 Snellen’s line or CMT increased by at least 10% from the previous visit in both groups. Main Outcome Measures: Comparison of change in vision and CMT at 1-year follow-up in DEX versus IVA groups. Results: Eighty-four eyes of 84 patients aged 54.4 + 4.4 years were included, 39 (46%) received DEX and 45 (54%) received IVA. Groups were comparable for baseline vision and CMT. Vision improved equally in both groups from 0.83 + 0.15 logMAR to 0.52 + 0.10 logMAR at 3 months (P < 0.01) and then stabilized till 1 year. However, eyes in the IVA group were 6.5 times more likely (Odds ratio = 6.45, 95% CI = 1.3 – 31.9) to achieve >3-line improvement in vision. The CMT reduction was also comparable between groups (-169 + 51 in DEX vs. -174 + 49 in IVA, P = 0.67). More eyes in the IVA group required >3 injections (91% vs. 69% in DEX, P = 0.01). The IOP was significantly higher at 6 and 9 months in the DEX group and 5 eyes (13%) required IOP lowering medications. Conclusion: In pseudophakic eyes with recalcitrant DME not responding to ranibizumab, switching to IVA or DEX implant results in equal visual improvement and CMT reduction. Though >3-line improvement occurs more frequently with IVA, this comes at the expense of a greater number of injections and follow-up visits.