To report one year findings of trial comparing two doses of intravitreal ziv-aflibercept (IVZ) with intravitreal bevacizumab (IVB) for treatment of center-involving diabetic macular edema (DME).

In this clinical trial, eyes with DME were randomly assigned to 2.5mg intravitreal ziv-aflibercept (42 eyes), 1.25mg intravitreal ziv-aflibercept (42 eyes), and 1.25mg IVB injections (39 eyes), every 4 weeks for 3 loading injections and then every 4 weeks for IVB and every 8 weeks for ziv-aflibercept injections. The patients were followed up to 1 year with complete ophthalmologic examination and central macular thickness (CMT) measurement by optical coherence tomography.

While no significant difference was evident between two ziv-aflibercept groups at 1 year, best-corrected visual acuity (BCVA) change was significantly better in both ziv-aflibercept groups than the IVB group at final follow-up (P=0.007 for IVZ 2.5 mg and P=0.029 for IVZ 1.25 mg). Regarding CMT changes, there was no significant difference between two ziv-aflibercept groups; however, a significantly more reduction in CMT was observed in the ziv-aflibercept 2.5mg group in comparison to the IVB group at 1 year (P=0.029). Subgroup analysis disclosed no difference in BCVA outcomes at 1 year among the eyes with baseline BCVA >20/50 in ziv-aflibercept groups compared to the IVB group. In the eyes with baseline BCVA ≤20/50 nonetheless, the improvement was significantly better at 1 year in both ziv-aflibercept groups compared to the IVB group (P=0.002 for IVZ 2. 5 mg and P=0.001 for IVZ 1.25 mg).

The 1-year results of this trial disclosed more vision improvement of intravitreal ziv-aflibercept compared to intravitreal bevacizumab in the treatment of center-involving DME. This stronger effect of intravitreal ziv-aflibercept however, was detected in the eyes with initial worse level of vision (≤20/50).