The ZIPANGU study assessed the efficacy and safety of
ranibizumab as a one loading dose + pro re
nata (one + PRN) regimen with/without focal/grid
laser among treatment-naïve patients suffering from
macular edema (ME) following
branch retinal vein occlusion (BRVO). ZIPANGU was a phase IV, prospective, randomized, open-label, active-controlled, 12-month, two-arm, multicenter study. Treatment-naïve patients with
visual impairment (19-73 letters) caused by ME, defined as central subfield thickness (CSFT) > 300 µm, due to BRVO were randomly assigned to
ranibizumab monotherapy (n = 29) or combination
therapy (ranibizumab + focal/grid short-pulse
laser, n = 30). The primary endpoint was the number of
ranibizumab injections. Secondary endpoints were mean changes in best-corrected visual acuity (BCVA) and CSFT, and safety. There were no statistically significant differences in the mean number of
ranibizumab injections between monotherapy (4.3
injections) vs. combination (4.1
injections)
therapy, or in CSFT. BCVA improvement in the monotherapy arm (22.0 letters) was better than the combination
therapy arm (15.0 letters) (p = 0.035). Overall, both regimens appeared to be safe and well tolerated. One + PRN
ranibizumab is safe and efficacious in treatment-naïve patients with ME secondary to BRVO. A conjunctive
laser treatment did not lead to better functional outcomes or fewer
ranibizumab injections.