Intravitreal aflibercept alone versus combination with dexamethasone phosphate for diabetic macular edema: A randomized phase-2 clinical trial

To compare the short-term (3-month) outcomes of intravitreal aflibercept injections versus intravitreal aflibercept combined with dexamethasone sodium phosphate in treating diabetic macular edema. In this Phase-2 clinical trial, 16 eyes of 16 participants with diabetic macular edema were randomly assigned to one of 2 groups. Participants in the aflibercept monotherapy group received 2 mg of intravitreal aflibercept (0.05 mL), while those in the combination therapy group received 2 mg of intravitreal aflibercept (0.05 mL) plus 0.04 mg dexamethasone sodium phosphate (0.01 mL). Identical injections were repeated after 30 and 60 days. The primary outcome was the change in central macular thickness, as measured by optical coherence tomography, from baseline to 1 month after the last injection. Secondary outcomes included changes in best-corrected visual acuity and intraocular pressure over the same period. The mean baseline central macular thickness was 444 ± 86 μm in the combination therapy group and 394 ± 96 μm in the aflibercept monotherapy group (p=0.293). By day 90, the mean reduction in central macular thickness was significantly greater in the combination therapy group (176 ± 129 μm) compared to the aflibercept monotherapy group (54 ± 49 μm; p=0.034). Best-corrected visual acuity also improved significantly more in the combination therapy group, with a median gain of 0.31 ± 0.16 LogMAR, whereas the aflibercept monotherapy group experienced a minimal change (-0.06 ± 0.13 LogMAR; p=0.020). Intraocular pressure remained stable in both groups, with no significant difference (p=0.855). None of the participants developed elevated intraocular pressure (>21 mmHg) or required ocular hypotensive medications. No significant ocular or systemic adverse events were reported. The addition of dexamethasone sodium phosphate to the standard intravitreal aflibercept regimen for diabetic macular edema can improve short-term structural and functional outcomes. Brazilian Clinical Trials Registry (RBR-7468j4q).