Phase I, prospective, interventional, open-label, multicenter clinical trial to evaluate the safety of intravitreal PRO-169 through the presence of serum anti-drug antibodies (ADAs) to bevacizumab.

Inclusion Criteria:

1. Age ≥ 18 years.
2. Diagnosis of type 1 or type 2 diabetes.
3. Ability to provide signed informed consent.
4. Ability and willingness to comply with scheduled visits, treatment plan, and other study procedures.
5. All subjects (male and female) who are biologically capable of having children must agree and commit to using a barrier or hormonal contraceptive method (by any route of administration) for the entire duration of the study and for 3 months after the last intravitreal injection.
6. Female subjects who are biologically capable of having children must have a negative urine pregnancy test at the screening visit.
7. Best-corrected visual acuity (BCVA) according to the ETDRS chart from 24 to 78 letters (approximate Snellen equivalent of 20/32 to 20/320).
8. Diabetic macular edema with central involvement evidenced by spectral domain optical coherence tomography (central macular thickness criterion > 300 µm for men and > 290 µm for women) within 8 days prior to inclusion. All measurements taken on a subject must be taken with an instrument of the same make and model throughout the study.
9. Meet characteristics that allow for adequate fundus examination (media transparency, adequate pupil dilation).
10. Glycosylated hemoglobin < 12% from a result no older than 3 months.

Exclusion Criteria:

1. Chronic kidney disease with renal failure (glomerular filtration rate [eGFR] <15 mL/min/1.73 m2) requiring dialysis or transplantation; according to the 2020 Clinical Practice Guideline for the Management of Diabetes in Chronic Kidney Disease from the Kidney Disease Improving Global Outcomes (KDIGO) organization.
2. Active proliferative diabetic retinopathy in the study eye, including rubeosis iridis, vitreous hemorrhage, or tractional retinal detachment visible during the screening visit.
3. Individuals who have required initiation of insulin therapy for glycemic control within 4 months prior to the screening visit.
4. Previous participation in clinical studies with investigational products, ocular or systemic (at least 30 days must have elapsed between the end of participation in a previous trial and inclusion in this study).
5. Known hypersensitivity or allergy to bevacizumab or any ingredient in the investigational product.
6. Poorly controlled blood pressure (average of 3 blood pressure readings in a seated position with ≥160 mmHg systolic or ≥100 mmHg diastolic) at the screening visit.
7. Myocardial infarction or other cardiovascular event (cerebrovascular disease, transient cerebral ischemia, or hospitalization for heart failure) during the 4 months prior to the screening visit, or subjects with active myocardial ischemia.
8. Systemic treatment with VEGF-related drugs within 4 months prior to the screening visit.
9. History of any rheumatological or collagen disease of autoimmune origin related to inflammatory processes such as: systemic lupus erythematosus, rheumatoid arthritis, ankylosing spondylitis, Behçet's disease, dermatomyositis, among others.
10. History of any disease that causes immunosuppression or immunodepression, except diabetes mellitus.
11. Concomitant use of immunosuppressive agents, immunotherapy, or monoclonal antibodies by any route of administration (other than intravitreal) in the 2 years prior to the screening visit or during the study period.
12. Subjects who have received intravitreal anti-VEGF treatment (aflibercept, ranibizumab, bevacizumab, faricimab, brolucizumab) in the study eye within 4 months prior to the screening visit.
13. Use of intraocular or periocular corticosteroids in the study eye within 4 months prior to the screening visit, or use of intravitreal corticosteroid implants at any time.
14. Use of anticoagulants or antiplatelet agents by any route of administration within 10 days prior to the screening visit or during the study period.
15. Women of childbearing potential who are pregnant, breastfeeding, or planning to become pregnant during the study period.
16. Allergy to fluorescein (topical or intravenous) or to anesthetic medications used during the injection procedure.
17. Subjects with non-diabetic macular edema.
18. Lens opacities that, according to the LOCS III (Lens Opacities Classification System) classification, exceed one or more of the following criteria: nuclear component > NO3C3 (opalescence/color), cortical component > C2, and posterior subcapsular component > P1.
19. History of eye surgery (cataract extraction, any intraocular surgery, aphakia, etc.) or panretinal photocoagulation within 3 months prior to the screening visit or planned within the study period.
20. Intraocular pressure greater than 21 mmHg in the selected eye, measured by Goldmann tonometry at the screening visit.
21. Presence of macular ischemia or significant perifoveal capillary loss (increase in foveal avascular zone greater than 350 µm) demonstrated by fluorescein retinal angiography (during the screening visit or in a study performed within 4 months prior to the screening visit).
22. History of YAG capsulotomy in the study eye within 30 days prior to the screening visit.
23. Evidence of external eye infections, intraocular inflammation, or significant ocular surface disease in either eye within 30 days prior to the screening visit.
24. History of uveitis in the study eye.
25. History of retinal detachment, vitrectomy, any type of filtering surgery, corneal transplant, or corneal dystrophy in the selected eye.
26. Advanced glaucoma or optic neuropathy in the selected eye.
27. Having only one functional eye (best corrected visual acuity of finger counting or less in the eye with the worst vision).
28. Having previously participated in this same study.
29. Being or having an immediate family member (e.g., parent/legal guardian or sibling) who is part of the research site staff or sponsor.
30. Subjects with conditions that make it difficult or impossible to draw blood, such as veins that are difficult to see or feel, venous thrombosis in the area where the sample is taken, severe edema, or any other criteria determined by the personnel responsible for performing this procedure.
31. Difficulty interpreting the optotypes on the ETDRS chart.