Primary Intravitreal Bevacizumab (Avastin) for Diabetic Macular Edema. Results from the Pan-American Collaborative Retina Study Group at 6-Month Follow-up

Purpose: To report the 6-month anatomic and best-corrected visual acuity (BCVA) response after primary intravitreal bevacizumab (Avastin) in patients with diabetic macular edema (DME). Design: Interventional retrospective multicenter study at 6 centers from 6 countries of patients with DME. Participants: We reviewed the clinical records of 88 consecutive patients (110 eyes) with DME. Seventy-eight eyes of 64 consecutive patients with a minimum follow-up of 6 months and mean age of 59.7±9.3 years were included in this analysis. Intervention: Patients were treated with at least one intravitreal injection of 1.25 mg or 2.5 mg of bevacizumab and underwent Early Treatment Diabetic Retinopathy Study (ETDRS) BCVA testing, ophthalmoscopic examination, optical coherence tomography (OCT), and fluorescein angiography (FA) at baseline and follow-up visits. Repeated-measures analysis of variance was used to compare mean values. Main Outcome Measures: Changes in BCVA, OCT, and FA. Results: Mean follow-up was 6.31±0.81 months (range, 6-9). Sixteen (20.5%) eyes needed a second injection at a mean of 13.8 weeks (range, 4-28), and 6 eyes needed a third injection (7.7%) at a mean of 11.5 weeks (range, 5-20). The mean baseline BCVA was 0.87 (logarithm of the minimum angle of resolution), and the final mean BCVA was 0.6, a difference that was statistically significant (P<0.0001). Final BCVA analysis by subgroups demonstrated that 32 (41.1%) eyes remained stable, 43 (55.1%) improved ≥2 ETDRS lines of BCVA, and 3 (3.8%) decreased ≥2 ETDRS lines of BCVA. Mean central macular thickness at baseline by OCT was 387.0±182.8 μm and decreased to a mean of 275.7±108.3 at end of follow-up (P<0.0001). No ocular or systemic adverse events were observed. Conclusions: Primary intravitreal bevacizumab at doses of 1.25 to 2.5 mg seem to provide stability or improvement in VA, OCT, and FA in DME at 6 months. Follow-up is still short to make any specific treatment recommendations; however, the results appear promising. Evaluation in a multicenter randomized controlled clinical trial with longer follow-up is needed.