Dosing Study of Ranibizumab for Diabetic Retinal and Macular Edema

• Mean number of injections. [ Time Frame: 12 months ] [ Designated as safety issue: No ]
  The average number of intravitreal ranibizumab injections in each arm of the study will be recorded.
• Mean change in spectral domain optical coherence tomography (SD-OCT) central foveal thickness (CFT). [ Time Frame: 12 months ] [ Designated as safety issue: No ]
  Evaluate the average change in the swelling from diabetic macular edema measured with the optical coherence tomography machine.
• Percentage of patients with best corrected visual acuity (BCVA) Snellen-equivalent of 20/40 or better. [ Time Frame: 12 months ] [ Designated as safety issue: No ]
  The percentage of patients with 20/40 vision as assessed by the number of letters read correctly on the ETDRS eye chart at a starting test distance of 20 feet.
• Percentage of patients anatomically "dry." [ Time Frame: 3, 6, and 12 months. ] [ Designated as safety issue: No ]
  Spectral domain OCT will be used to check the patients' central foveal thickness at each visit and the percentage with "dry" maculas at months 3,6, and 12 based on spectral domain OCT measurements per the study protocol will be recorded.
• Number of participants with adverse events as a measure of safety and tolerability. [ Time Frame: 12 months ] [ Designated as safety issue: Yes ]
  To evaluate the safety and tolerability of ranibizumab for diabetic macular edema by recording local and systemic adverse events.

This study is to see whether treating diabetic retinal swelling with ranibizumab injections into the eye monthly is better than treating diabetic retinal swelling with ranibizumab injections into the eye less frequently.

This is a prospective randomized study comparing two groups of patients with diabetic macular edema. One group will receive injections of ranibizumab monthly and the other group will have the option to receive injections of ranibizumab less frequently. That is eligible to receive the injections less frequently will have fewer injections given if the patients in that group are doing well.

• Diabetic Retinopathy
• Macular Edema

• Active Comparator: Monthly Ranibizumab
  Patients randomized to the Monthly Ranibizumab arm of the study will be administered intravitreal injections each month for their diabetic macular edema for the duration of the study.
  Intervention: Drug: Ranibizumab
• Experimental: Treat and Extend Ranibizumab
  Patients randomized to this arm of the study will receive intravitreal injections of ranibizumab until their maculae are anatomically "dry," at which point the evaluation and injection interval will be extended.
  Intervention: Drug: Ranibizumab

Inclusion Criteria:

• Ability to provide written informed consent and comply with study assessments for the full duration of the study
• Age > 18 years
• Patient related considerations
• Phakic or pseudophakic patients with a known history of diabetes will be eligible.
• Women of reproductive age will be required to take a urine pregnancy test prior to administration of the study drug.
• Disease related considerations:
• Patients will have met standard, accepted diagnostic criteria for diabetes and will be currently treated with at least one systemic antihyperglycemic or insulin medication.
• Patients will have a BCVA ETDRS Snellen-equivalent less than or equal to 20/40
• Central foveal thickness on SD-OCT of >300um

Exclusion Criteria:

• Pregnancy (positive pregnancy test) or lactation Premenopausal women not using adequate contraception. The following are considered effective means of contraception: surgical sterilization or use of oral contraceptives, barrier contraception with either a condom or diaphragm in conjunction with spermicidal gel, an IUD, or contraceptive hormone implant or patch.
• Any other condition that the investigator believes would pose a significant hazard to the subject if the investigational therapy were initiated
• Participation in another simultaneous medical investigation or trial
• Foveal ischemia on IVFA
• Intraocular surgery less than 6 months ago
• Epiretinal membrane of clinical significance
• Prior vitrectomy
• Uncontrolled glaucoma
• Macular or peripheral laser within 90 Days from Day 0 injection
• Intravitreal steroid injection within 90 days from Day 0 injection
• Intravitreal or systemic anti-VEGF within 30 days from Day 0 injection