Intravitreal Conbercept After Vitrectomy

Study Overview
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Brief Summary
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To evaluate the safety and efficacy of intravitreal conbercept after vitrectomy for the management of early-stage proliferative diabetic retinopathy (PDR). Hypothesis: intravitreal conbercept therapy may promote functional and anatomic recovery from PDR. intravitreal conbercept therapy may be a useful and safe method for improving visual outcomes of surgery for early-stage PDR.

Detailed Description
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The drug conbercept (an anti-vascular endothelial growth factors) was recently made available for management of early prolific diabetic retinopathy, but its safety and efficacy still require study. Therefore, the aim is to evaluate the safety and efficacy of intravitreal conbercept after vitrectomy for the management of early proliferative diabetic retinopathy.The patients were randomly assigned (25 eyes each group) to either treatment group and control after they provided informed consent. The treatment group received intravitreal conbercept (10 mg/mL, 0.5 mg) immediately after surgery, while the control group did not. At the time of study enrollment, physical examinations, best-corrected visual acuity (BCVA), intraocular pressure and central retinal thickness will be measured and fundoscopy be performed. The patients are going to be followed up for at least 6 months via BCVA measurement, fundoscopy, OCT, physical examinations and postoperative complications

Official Title
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Safety and Efficacy of Intravitreal Conbercept Injection After Vitrectomy for the Treatment of Early Proliferative Diabetic Retinopathy

Conditions
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Early Proliferative Diabetic Retinopathy

Intervention / Treatment
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* Drug: Conbercept


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: We enrolled 50 eyes from 50 patients that were affected by VH as a consequence of early active PDR. Patients with non-clearing VH and fibrocellular proliferation without TRD who underwent PPV at Tianjin Medical University Eye Hospital were included in the study. Exclusion Criteria: A history of previous PPV; Severe intraoperative complications Postoperative silicone oil tamponade; Menstruation; Stroke, a thromboembolic event, or myocardial infarction in the previous months contraindicating the withdrawal of anti-platelet and anti-coagulant medications.

Ages Eligible for Study
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Minimum Age: 28 Years
Maximum Age: 80 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Conbercept<br>intravitreal conbercept (10 mg/mL, 0.5 mg) immediately after surgery | Drug: Conbercept<br>* Three-port 25-G PPV was performed in all patients using a Constellation system. Patients in the treatment group received an intravitreal injection of conbercept (10 mg/mL, 0.5 mg) using a sterile technique after 25-G vitrectomy.<br>|
| No Intervention: control group<br>Pars plana vitrectomy alone | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| best corrected visual acuity | BCVA using a Landolt C acuity chart method | baseline to 24 weeks post-surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| postoperative complications | postoperative complications | baseline to 24 weeks post-surgery | 
| central retinal thickness | Optical coherence tomography (OCT) is an established medical imaging technique that uses light to capture micrometer-resolution, one-dimensional images | baseline to 24 weeks post-surgery |