A Phase 2 Study to Evaluate the Efficacy and Safety of ENN0403 in Subjects with DME

Inclusion Criteria:

1. Provide written informed consent;

2. Aware of the entire study process and requirements, understands the importance ofmedication compliance and completing all assessments on time throughout the study,and agrees to strictly follow the protocol and study procedures, includingrestrictions on drug combination during the study;

3. Diagnosis of type 1 or type 2 diabetes mellitus and HbA1c≤10.0% with regular usehypoglycemic drugs and stable glycemic control 1 month before screening (at thediscretion of the investigator);

4. The decrease of BCVA is mainly caused byDiabetic Macular Edema in the study eye;

5. BCVA letter score of ≤ 73 (Snellen 20/40) and ≥ 24 (Snellen 20/320) at screeningvisit and at baseline. If both eyes meet the inclusion criteria, the study eye willbe determined by the investigator from a medical perspective. ( If both eyes meetthe inclusion criteria，the eye with poor baseline vision will be selected as thestudy eye; If the BCVA number is the same, choose the eye with the thicker CRT asthe study eye) ；

6. Optical Coherence Tomography (OCT) foveal CRT at screening measuring ≥300 μm.

Exclusion Criteria:

1. Study eye with any eye disease or medical history other than DME that causes or maycause irreversible vision loss;

2. Study eye had glaucoma filtration surgery in the past or may have the surgery duringthe study;

3. Study eye had previously undergone vitreoretinal surgery;

4. Study eye received intraocular hormone drugs within 6 months prior to baseline orperiocular or systemic hormone drugs within 3 months prior to baseline;

5. Any eye received intraocular injection of VEGF within 3 months prior to baseline;

6. History of idiopathic or autoimmune uveitis in any eye;

7. Uncontrolled glaucoma in any eye (defined as IOP ≥25 mmHg after treatment withanti-glaucoma drugs)

8. History of allergy to the investigational drug or any ingredient, or to anyingredient used during the treatment;

9. Use of any other investigational drug or device within 3 months or 5 half-livesprior to baseline (whichever is longer);

10. Other factors considered inappropriate for inclusion in this study at the discretionof the investigator.