Comparison of intravitreal injection of conbercept and triamcinolone acetonide for macular edema secondary to branch retinal vein occlusion

AIM: To compare the safety and efficacy of the intravitreal injection of conbercept (IVC) and triamcinolone acetonide (IVTA) for macular edema (ME) secondary to branch retinal vein occlusion (BRVO). METHODS: A prospective, randomized clinical study. Patients with ME secondary to BRVO were randomly assigned to either IVC group or IVTA group at a ratio of 2:1 and a 12-month follow-up was performed. The efficacy outcome measures included the mean changes and differences in best corrected visual acuity (BCVA) and the central retinal thickness (CRT). The safety profiles and the mean retreatment intervals were also compared. RESULTS: There was no statistically significant difference of baseline between the two groups (IVC group, n=36; IVTA group, n=17). At 12mo, the BCVA letters improved by 27.31 +/- 18.36 in the IVC group, and 13.53 +/- 11.37 in the IVTA group (P=0.0004). CRT reduction was 253.33 +/- 163.69 and 150.24 +/- 134.32 mu m, respectively (P=0.0034). The mean BCVA in the IVC group was superior to that of the IVTA group for months 6-12 (P<0.01). The mean CRT at 9 and 12mo were thinner in the IVC group compared to the IVTA group (P<0.01). The mean retreatment interval in the IVC group was longer than that in the IVTA group (97.40 +/- 36.27d vs 68.71 +/- 36.38d, P=0.0030). One eye in the IVC group and seven eyes in the IVTA group developed elevated intraocular pressure (IOP; P=0.0012). The proportion of eyes with cataract new-onset or progression were 19.44% in the IVC group and 64.71% in the IVTA group (P=0.0012). CONCLUSION: IVC could maintain or improve BCVA and reduce CRT for a longer time and have longer retreatment interval than IVTA. In addition, patients treated with IVTA are more susceptible to IOP elevation and cataract progression.