Preliminary Efficacy Analysis of Early Combination Therapy with Intravitreal Aflibercept and Dexamethasone Implant for Diabetic Macular Edema

Purpose To evaluate the differences in preliminary clinical efficacy and safety between intravitreal aflibercept monotherapy and early combination therapy with aflibercept and dexamethasone implant (DEX-I) for diabetic macular edema (DME). Methods Prospective study. Fifty-nine patients (59 eyes) diagnosed with DME at the Ophthalmology Department of Dalian Third People's Hospital between March 2024 and December 2024 were enrolled. Patients were divided into an aflibercept monotherapy group (30 patients, 30 eyes) and an aflibercept combined with DEX implant group (29 patients, 29 eyes). The monotherapy group received intravitreal injections of aflibercept (2mg/0.05ml) every 4 weeks for 4 doses, followed by a pro re nata (PRN) regimen until week 24. The combination group received an initial intravitreal injection of aflibercept (2mg/0.05ml) combined with DEX-I (0.7mg) in the same session. From week 4 to week 12, they received monthly aflibercept injections (2mg/0.05ml), followed by a PRN regimen until week 24. Before treatment, all patients underwent best-corrected visual acuity (BCVA) assessment using the ETDRS chart (letters recorded), slit-lamp examination, intraocular pressure (IOP) measurement, indirect ophthalmoscopy, spectral-domain optical coherence tomography (SD-OCT), and optical coherence tomography angiography (OCTA). After treatment, patients in both groups were assessed every 4 weeks ± 7 days until week 24. Results Compared to the monotherapy group, the combination group showed a significantly greater mean increase in BCVA from baseline to week 12 (P < 0.05). The mean BCVA increase from baseline to week 24 was also greater in the combination group (P = 0.094). The proportion of eyes gaining ≥ 15 letters from baseline at week 12 was 58.62% in the combination group versus 30% in the monotherapy group (P < 0.05). Compared to baseline, both groups showed statistically significant reductions in central retinal thickness (CRT) at all follow-up time points (P < 0.001 for all). The difference in CRT reduction between the monotherapy and combination groups was statistically significant at 20 weeks post-injection (P < 0.05). Conclusions Compared to aflibercept monotherapy, early combination therapy with aflibercept and DEX-I resulted in faster visual acuity improvement, greater reduction in central macular thickness, and reduced edema fluctuation in the early treatment phase for DME.