The purpose of this study is to evaluate the safety, pharmacokinetics, pharmacodynamics, and pilot efficacy of multiple ascending dose levels of AKB-9778 given as subcutaneous injections daily for 28 days in patients with diabetic macular edema (DME).

Inclusion Criteria:

The following is an abbreviated list of inclusion criteria:

• Adults between 18 to 80 years of age, inclusive
• Diagnosis of diabetes mellitus (type 1 or type 2)
• Decrease in vision determined to be primarily the result of DME in the study eye
• Definite Retinal thickening due to diffuse DME involving the center of the macula in the study eye
• Mean central subfield thickness of at least 325 µm by OCT in the study eye
• Early Treatment Diabetic Retinopathy Study (ETDRS) letter score BCVA ≤ 70 (20/40) in the study eye

Exclusion Criteria:

The following is an abbreviated list of exclusion criteria:

• Hemoglobin A1C (HbA1C) ≥ 11.5%

• History of any of the following in the study eye (however, the following are not exclusionary in the fellow eye):

  1. Panretinal scatter photocoagulation (PRP) or focal laser within 12 weeks prior to Screening
  2. Prior pars plana vitrectomy within 12 weeks prior to Screening
  3. Any ocular surgery within 12 weeks prior to Screening
  4. YAG capsulotomy within 7 days prior to Screening
  5. Prior intravitreal, subtenon, or periocular steroid therapy within 3 months prior to Screening or prior treatment with intravitreal anti-VEGF treatment within 1 month of Screening