A Randomized Controlled Trial of Conbercept Pretreatment before Vitrectomy in Proliferative Diabetic Retinopathy

Abstract

Purpose. To determine the efficacy and safety of preoperative intravitreal conbercept (IVC) injection before vitrectomy for proliferative diabetic retinopathy (PDR). Methods. 107 eyes of 88 patients that underwent pars plana vitrectomy (PPV) for active PDR were enrolled. All patients were assigned randomly to either preoperative IVC group or control group. Follow-up examinations were performed for three months after surgery. The primary bioactivity measures were severity of intraoperative bleeding, incidence of early and late recurrent VH, vitreous clear-up time, and best-corrected visual acuity (BCVA) levels. The secondary safety measures included intraocular pressure, endophthalmitis, rubeosis, tractional retinal detachment, and systemic adverse events. Results. The incidence and severity of intraoperative bleeding were significantly lower in IVC group than in the control group. The average vitreous clear-up time of early recurrent VH was significantly shorter in IVC group compared with that in control group. There was no significant difference in vitreous clear-up time of late recurrent VH between the two groups. Patients that received pretreatment of conbercept had much better BCVA at 3 days, 1 week, and 1 month after surgery than control group. Moreover, both patients with improved BCVA were greater in IVC group than in control group at each follow-up. Conclusions. Conbercept pretreatment could be an effective adjunct to vitrectomy in accelerating postoperative vitreous clear-up and acquiring stable visual acuity restoration for PDR.

Figure 1

Chart showing participants flow. IVC: intravitreal conbercept; PPV: pars plana vitrectomy; SO: silicone oil.

Figure 2

Bar graph showing incidence of early and late recurrent VH with or without conbercept pretreatment after surgery. Subgroup pairwise analysis showed significant differences in early recurrent VH incidence between preoperative IVC group and control group. However, there was no statistically significant difference in late recurrent VH in both groups (P < 0.001, P = 0.732, resp.). VH: vitreous hemorrhage; IVC: intravitreal conbercept.

Figure 3

Graph showing vitreous clear-up time of early and late recurrent vitreous hemorrhage in participants with or without conbercept pretreatment. Subgroup pairwise analysis showed significant differences between IVC group and control group in early recurrent VH clear-up time (P < 0.001), but no statistical differences in late recurrent VH clear-up time between the two groups (P > 0.05). VH: vitreous hemorrhage; IVC: intravitreal conbercept.

Figure 4

Bar graph showing best-corrected visual acuity levels in participants with or without conbercept pretreatment preoperatively and at 3 days, 1 week, 1 month, and 3 months after surgery. Subgroup pairwise analysis showed significant differences of visual acuity levels at 3 days (P = 0.025), 1 week (P = 0.012), and 1 month (P = 0.047) after surgery between preoperative IVC group and control group. However, there was no statistically significant difference at 3 months (P = 0.114) after surgery between the two groups. Compared with the preoperative period, visual acuity levels had a significant increase at 3 months after surgery in both groups (P < 0.001, P = 0.010, resp.). IVC: intravitreal conbercept; pre-op: preoperative; post-op: postoperative.