sponsor withdrew funding

The purpose of this study is to specifically assess the effect of intravitreal aflibercept injections on the health of cells and the flow of blood through the retinal blood vessels by using advanced technology called adaptive optics.

Inclusion Criteria:

• Documented Type 1 or 2 diabetes mellitus who have moderately severe to severe NPDR (DRSS levels 47 or 53) as confirmed by 2 independent physician evaluators.
• Age ≥18 years
• Willingness and the ability to provide signed informed consent, comply with clinic visits and study-related procedure, and provide Health Insurance Portability and Accountability Act authorization
• BCVA of ≥ 73 letters, inclusive (≥20/40 approximate Snellen equivalent), using the ETDRS protocol at the initial testing distance of 4 meters (see the BCVA manual for additional details) on Day 1
• Sufficiently clear ocular media and adequate pupillary dilatation to allow acquisition of good quality CFPs (including ETDRS 7 modified fields or Optos ultra-widefield image to permit grading of diabetic retinopathy and assessment of the retina) and other imaging modalities, including AOSLO.
• No center-involved macular edema (defined as fluid within 1000 microns of the fovea)
• HbA1c of ≤10% within 2 months prior to the first injection visit date
• For men* and women** of childbearing potential: agreement to remain abstinent (refrain from heterosexual intercourse) or use acceptable contraceptive methods that result in a failure rate of <1% per year during the treatment period and for at least 3 months after the final dose of study treatment. Adequate contraceptive measures include stable use of oral contraceptives or other prescription pharmaceutical contraceptives for 2 or more menstrual cycles prior to screening; intrauterine device; bilateral tubal ligation; vasectomy; condom plus contraceptive sponge, foam, or jelly, or diaphragm plus contraceptive sponge, foam, or jelly. Contraception is not required for men with documented vasectomy. Postmenopausal women must be amenorrheic for at least 12 months in order not to be considered of childbearing potential. Pregnancy testing and contraception are not required for women with documented hysterectomy or tubal ligation.

Exclusion Criteria:

• Presence of DME threatening the center of the macula (within 1,000 microns of the foveal center) in the study eye
• Evidence of retinal neovascularization on clinical examination or FA
• Any prior focal or grid laser photocoagulation (within 1,000 microns of the foveal center) or any prior PRP in the study eye
• Any prior systemic anti-VEGF treatment or IVT anti-VEGF treatment in the study eye
• Any prior intraocular steroid injection in the study eye
• History of vitreoretinal surgery in the study eye
• Intraocular pressure (IOP) ≥25 mm Hg in the study eye
• Evidence of active infectious blepharitis, keratitis, scleritis, or conjunctivitis in either eye
• Any intraocular inflammation or infection in either eye within 3 months of the screening visit
• Current Anterior segment neovascularization, vitreous hemorrhage, or tractional retinal detachment visible at the screening assessments in the study eye
• Ocular media of insufficient quality to obtain fundus and optical coherence tomography (OCT), and adaptive optics images in the study eye
• Hemoglobin A1c (HbA1c) >12%, or if HbA1c is ≤12%, diabetes mellitus is uncontrolled in the opinion of the investigator
• Any concurrent ocular condition in the study eye which, in the opinion of the investigator, could either increase the risk to the patient beyond what is to be expected from standard procedures of IVT injections, or which otherwise may interfere with the injection procedure or with evaluation of efficacy or safety
• Uncontrolled blood pressure (defined as systolic >160 mm Hg or diastolic >95 mm Hg while patient is sitting)
• History of cerebrovascular accident or myocardial infarction within 6 months of day 1
• Renal failure, dialysis, or history of renal transplant
• Positive serum hCG/urine pregnancy test at the screening or baseline visit
• History of other disease, metabolic dysfunction, physical examination finding, or clinical laboratory finding giving reasonable suspicion of a disease or condition that contraindicates the use of an investigational drug or that might affect interpretation of the results of the study or render the patient at high risk for treatment complications
• Participation as a patient in any interventional ocular clinical study within the 12 weeks prior to day 1 of the study
• Sexually active men* or women of childbearing potential** who are unwilling to practice adequate contraception prior to the initial dose/start of the first treatment, during the study, and for at least 3 months after the last dose. Adequate contraceptive measures include stable use of oral contraceptives or other prescription pharmaceutical contraceptives for 2 or more menstrual cycles prior to screening; intrauterine device; bilateral tubal ligation; vasectomy; condom plus contraceptive sponge, foam, or jelly, or diaphragm plus contraceptive sponge, foam, or jelly. Contraception is not required for men with documented vasectomy.

Postmenopausal women must be amenorrheic for at least 12 months in order not to be considered of childbearing potential. Pregnancy testing and contraception are not required for women with documented hysterectomy or tubal ligation.