Intravitreal Conbercept For Branch Retinal Vein Occlusion induced Macular Edema: One Initial Injection Versus Three Monthly Injections

Abstract

Objective To compare the efficacy of one initial intravitreal injection of conbercept (IVC) versus three monthly IVCs in patients with macular edema (ME) after branch retinal vein occlusion (BRVO). Both options were followed by a pro re nata (PRN) retreatment regimen.Methods This study retrospectively investigated and followed 49 patients with acute ME secondary to BRVO for over a year. 24 subjects received one initial injection (1+PRN group); while, 25 received three monthly injections (3+PRN group). The functional and anatomic outcomes were assessed during each follow-up.Results The general characteristics of the 49 subjects were as follows: mean [SD] age, 56.12 [12.54] years; 28 [57.1%] female; 30 [61.2%] non-ischemic form. Both groups showed a stable gain in visual acuity (VA) with similar logMAR (mean ± SD) (1+PRN group 0.308±0.431, 3+PRN group 0.345±0.366) during the first 12 months. Additionally, both groups exhibited a significant reduction in central foveal thickness (CFT) with no statistically significant difference between them (1+PRN group 220.5 μm ±219.9 μm , 3+PRN group 230.2 μm ±220 μm ). Both treatment groups had similar improvements in logMAR and anatomic outcomes over time. The stratified analysis showed that patients with the non-ischemic form and those with the ischemic form had similar improvements in VA (0.351±0.387 VS 0.289±0.417, P =0.601) during the 12 months follow-ups. The number of injections was lower in the 1+PRN group (4.0±1.7) than in the 3+PRN group (4.6±1.2) ( P =0.155). No adverse effects or unexpected safety issues were reported in either group.Conclusions Conpercept yielded stronger improvements in VA and CFT among patients with BRVO induced ME，independent of their retinal ischemia status. The results showed that the 3+PRN regimens do not lead to better functional outcomes or lower treatment needs in clinical practice as compared to the 1+PRN regimen.

Analysis On Short-Term Change of Macular Function and The Correlates After Intravitreal Conbercept for CRVO-ME

“…[2] reported that the functions of retinal ganglion cells and cone cells did not change in a short time after bevacizumab was used in AMD, high myopia CNV, PDR, and RVO.Rohit Shetty [14] came to a different conclusion, research showed that mf-ERG increased slightly to moderately in a short time after intravitreal injection of bevacizumab, but it was not directly related to the best corrected visual acuity and the improvement of retinal thickness in fovea maculae.Compared with monoclonal antibody drugs such as ranibizumab.Conbercept, however as a fusion protein, can bind to the extracellular domain 2 of VEGF receptor 1 and the extracellular domains 3 and 4 of VEGF receptor 2. [15] This study showed that conbercept had the same or even better effect in RVO-ME patients. The conclusion of this study was consistent with Rohit Shetty's, after treatment, the macular function was signi cantly improved at one week and two months compared with the baseline, which con rmed that conbercept had no toxic effect on cones and inner retinal cells in a short time.The rst and second rings of mf-ERG re ects the fovea and inner retinal function within 10°.…”