This is a 12-month, prospective, randomized controlled, multi-center, open-label, superiority designed study. Treatment-Naïve DME patient with inflammatory biomarkers, who meet the inclusion and exclusion criteria, will be recruited.

This study aims to provide the first direct comparative evidence within a Chinese cohort, evaluating the efficacy and safety of a combined DEX-I plus aflibercept therapy versus aflibercept monotherapy for DME. The investigation will focus on functional visual outcomes, anatomical improvements, and the respective safety profiles associated with each treatment regimen. Furthermore, the study will incorporate specific optical coherence tomography (OCT) biomarkers to refine patient selection, with the goal of enhancing the precision of identifying candidates for combination therapy.

It is hypothesized that the combination therapy, by concurrently targeting both VEGF-mediated and inflammatory pathways, may yield superior clinical outcomes compared to monotherapy.

Inclusion Criteria:

All of the following conditions must be met simultaneously:

1. Age ≥ 18 years, diagnosis of diabetes mellitus (type Ⅰor type Ⅱ).
2. With good glycaemic control and glycated haemoglobin ≤10.0%.
3. DR stage II-IV.
4. Treatment with aflibercept intravitreal injection is planned for center-involved diabetic macular edema (CI-DME) , Central macular thickness (CMT) ≥300 μm in the 1-mm-diameter zone around fovea with best corrected visual acuity(BCVA) <20/25.
5. Presence on OCT imaging of one or more of the following findings in the study eye(within 1000-μm-diameter of the center of the fovea): central macular thickness (CMT) ≥500μm, foveal intraretinal cystoid spaces ≥300μm in height or ≥250μm in width(large IRC), serous retinal detachment (SRD), Intraretinal hyperreflective dots (HRDs), Hard exudates (HEs).
6. No refractive interstitial clouding and pupillary constriction affecting fundus examination.

Exclusion Criteria:

1. Grade III and IV cataracts, or those with post-comorbid subcapsular cataracts,
2. Other macular degeneration such as Macular epiretinal membrane and Macular Hole, etc., or macular edema caused by other causes such as uveitis, retinal vein occlusion, etc.,
3. Combined with diabetic optic neuropathy,
4. Any prior use of an approved or investigational treatment for DME in the study eye such as anti-VEGF drugs or corticosteroids drugs etc.,
5. History of vitreoretinal surgery and/or including scleral buckling in the study eye,
6. Transscleral fixated IOLs and ruptured posterior lens capsule,
7. Active or suspected ocular and periocular infections,
8. Advanced glaucoma or uncontrolled glaucoma with anti-glaucoma drugs; Or a history of glucocorticoid-induced elevated intraocular pressure,
9. Systemic conditions such as asthma, severe hypertension, cerebrovascular accident or myocardial infarction, or other reasons for not being able to co-operate with the relevant examination,
10. Pregnant or lactating,
11. Patients with hypersensitivity to dexamethasone or to any other components of the product,
12. Patients are allergic to aflibercept or any of the ingredients Aflibercept Intravitreous Injection.