Comparison of Interval Variation and Dosage in Preoperative Bevacizumab and Ziv-Aflibercept Administration in Proliferative Diabetic Retinopathy Undergoing Vitrectomy

Summary

Participation Requirements

Description

Severe vision loss in patients with proliferative diabetic retinopathy (PDR) frequently results from complications related to neovascularization and fibrovascular proliferation. Patients with PDR are typically considered candidates for pars plana vitrectomy (PPV) when non-clearing vitreous hemorrhag...

Severe vision loss in patients with proliferative diabetic retinopathy (PDR) frequently results from complications related to neovascularization and fibrovascular proliferation. Patients with PDR are typically considered candidates for pars plana vitrectomy (PPV) when non-clearing vitreous hemorrhaging, tractional retinal detachment (TRD) development or extensive fibrovascular proliferation occur. Visual prognosis is guarded in patients undergoing PPV with these advanced presentations of PDR because of the high rate of both intra-operative and postoperative complications. Intra-operative bleeding may result in poor visualization during PPV that increases total surgery time and ultimately leads to surgical failure, while recurrent/persistent postoperative vitreous hemorrhage may occur as high as 75% and hinder visual rehabilitation and monitoring of further disease progression. Preoperative administration of bevacizumab (Avastin; Genentech, Inc, South San Francisco, California, USA), a full-length recombinant humanized monoclonal antibody targeting vascular endothelial growth factor (VEGF), has been reported in prospective clinical trials to decrease the overall surgery time, lower the rate of intra-operative complications, and reduce the occurrence of postoperative hemorrhaging in PDR patients with active neovascularization and/or extensive fibrovascular proliferation undergoing PPV. Furthermore, two meta-analysis studies examining published randomized controlled trials support the use of intravitreal bevacizumab (IVB) as a preoperative adjunct. Although IVB is widely used as a preoperative adjunct in patients with PDR undergoing PPV, little clinical data is available regarding the optimal timing of preoperative IVB administration or the most effective dose. In this randomized clinical study, we attempt to elucidate the most appropriate interval and dose for the administration of preoperative IVB in patients with PDR undergoing PPV for non-clearing vitreous hemorrhaging, TRD or extensive fibrovascular proliferation. Ziv-aflibercept (Zaltrap, Regeneron) is a recombinant fusion protein that acts as a soluble decoy receptor and binds to VEGF-A, VEGF-B, and placental growth factor, similar to aflibercept (Eylea, Regeneron, Tarrytown, NY), which is FDA approved for intravitreal administration to treat various retinal diseases. At the dose of 1.25 mg/0.05 mL, ziv-aflibercept has been reported to safely and effectively treat neovascular macular degeneration and diabetic macular edema, similar in efficacy to bevacizumab. Presently, there are no reports regarding the effectiveness of preoperative ziv-aflibercept administration prior to PPV for PDR. In this randomized clinical trial, we also evaluate the effectiveness of ziv-aflibercept to bevacizumab, and attempt to elucidate the most appropriate interval for the administration of preoperative ziv-aflibercept in patients with PDR undergoing PPV for non-clearing vitreous hemorrhaging, TRD or extensive fibrovascular proliferation.

Tracking Information