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Day Regimes of CONbercept on CytokinEs of PDR Patients Undergoing Vitrectomy - Trial (CONCEPT)

Phase 4
Conditions
VEGF Overexpression
Proliferative Diabetic Retinopathy
Interventions
Drug: IVC
Procedure: Blood and aqueous humor at the time of IVC
Procedure: IVC-sham
Procedure: Collect blood, aqueous humor, and initial vitreous at the time of surgery.
Registration Number
NCT03506750
Lead Sponsor
The First Affiliated Hospital with Nanjing Medical University
Brief Summary

Patients with proliferative diabetic retinopathy requiring surgical intervention will receive a pre-operative injection of Conbercept. Patients will be recruited into different groups according to variable time intervals (1 to 7 days) between intravitreous injection and surgery. At initial, pre-injection aqueous humor and blood sample will be collected in order to provide baseline VEGF-A, -B, placental growth factor (PIGF), and other cytokine levels. At the onset of the vitrectomy, a second aqueous humor, blood, and vitreous sample will be taken to obtain intra-operative levels of , VEGF-A, -B, PIGF, and other cytokine levels.

Detailed Description

Proliferative diabetic retinopathy (PDR), characterized by neovascularization and fibrous proliferation, is a severe and common complication of diabetes mellitus (DM). Persistent vitreous hemorrhage (VH) caused by neovascularization and tractional retinal detachment (TRD) caused by fibrous proliferation can lead to permanent vision loss or even blindness, which are the most common indications for surgical intervention.

As neovascularization is the basal pathophysiological change of PDR and vascular endothelial growth factor (VEGF) has been acknowledged as primary angiogenesis factor, the preoperative adjunctive use of VEGF blockade is rationally proposed. The anti-VEGF drugs have been reported to be effective in bringing about regression of retinal neovascularization, shortening surgical duration, avoiding risk of iatrogenic retinal hole and secondary operation for the recurrent VH.

Conbercept (KH902) is a newly developed anti-VEGF drug and has been applied in clinic. Because of its additional binding domain of VEGFR-2, conbercept can bind to all isoforms of VEGF-A, VEGF-B, and placental growth factor (PLGF). A number of studies have presented its high affinity in the treatment of fundus diseases such as wet age-related macular degeneration (wet-AMD), macular edema secondary to retinal vein occlusion\[8\] and diabetic retinopathy. Also, recent randomized controlled trials have shown its protective effect of conbercept for the surgical treatment of PDR.

Although the overwhelming clinical evidence supports the anti-VEGF drugs as the preoperative adjuncts for PDR, the optimal duration between anti-VEGF injection and surgical intervention has not yet reached a consensus. Longer duration is related to higher incidence of the development or progression of TRD. It might provide clues by investigation of the pattern of cytokine changes in humor aqueous, vitreous, and blood. No studies have been done to date in patients with PDR to quantify the reduction of intravitreal VEGF-A, -B, PLGF or other cytokines levels in these patients following intravitreal Conbercept injection or to evaluate the effects of VEGF or PIGF blockade on the neovascular regression and surgical outcome in patients with extensive diabetic proliferative neovascularization.

The goal of this study is to quantify the reduction of changes of VEGF-A, -B, PLGF levels in patients receiving r pre-operative intravitreal Conbercept after variable time intervals (1, 2, 3, 4, 5, 6, 7 days).

Recruitment & Eligibility

Status
UNKNOWN
Sex
All
Target Recruitment
200
Inclusion Criteria
  • 18 years or older
  • Type 1 or 2 diabetes
  • PDR patients requiring surgical intervention for complications of vitreous hemorrhage or traction retinal detachment and pre-operative IVC treatment.
  • women postmenopausal for 12 months before the study, surgically sterile, or not pregnant and on effective contraception.
Exclusion Criteria
  • previous retinal vein occlusion.
  • any intraocular surgery within the previous 12 months.
  • myopia of > or = to 8 diopters.
  • active ocular or periocular infection
  • treatment with an investigational agent for any condition 60 days prior to enrollment.
  • evidence of severe cardiac disease.
  • clinically significant peripheral vascular disease (previous surgery, amputation, or symptoms of claudication)
  • uncontrolled hypertension (treated systolic blood pressure > 155 mmHg or diastolic blood pressure > 95 mmHg)
  • stroke within the preceding 12 months.

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
IVC-4dayBlood and aqueous humor at the time of IVCpatients with proliferative diabetic retinopathy receiving IVC 4 days before surgery
IVC-2dayIVCpatients with proliferative diabetic retinopathy receiving IVC 2 days before surgery
IVC-2dayCollect blood, aqueous humor, and initial vitreous at the time of surgery.patients with proliferative diabetic retinopathy receiving IVC 2 days before surgery
IVC-3dayIVCpatients with proliferative diabetic retinopathy receiving IVC 3 days before surgery
IVC-4dayIVCpatients with proliferative diabetic retinopathy receiving IVC 4 days before surgery
IVC-1dayBlood and aqueous humor at the time of IVCpatients with proliferative diabetic retinopathy receiving IVC 1 days before surgery
IVC-1dayCollect blood, aqueous humor, and initial vitreous at the time of surgery.patients with proliferative diabetic retinopathy receiving IVC 1 days before surgery
IVC-2dayBlood and aqueous humor at the time of IVCpatients with proliferative diabetic retinopathy receiving IVC 2 days before surgery
IVC-7dayCollect blood, aqueous humor, and initial vitreous at the time of surgery.patients with proliferative diabetic retinopathy receiving IVC 7 days before surgery
IVC-shamIVC-shampatients with proliferative diabetic retinopathy receiving sham IVC
IVC-1dayIVCpatients with proliferative diabetic retinopathy receiving IVC 1 days before surgery
IVC-3dayCollect blood, aqueous humor, and initial vitreous at the time of surgery.patients with proliferative diabetic retinopathy receiving IVC 3 days before surgery
IVC-4dayCollect blood, aqueous humor, and initial vitreous at the time of surgery.patients with proliferative diabetic retinopathy receiving IVC 4 days before surgery
IVC-5dayBlood and aqueous humor at the time of IVCpatients with proliferative diabetic retinopathy receiving IVC 5 days before surgery
IVC-5dayCollect blood, aqueous humor, and initial vitreous at the time of surgery.patients with proliferative diabetic retinopathy receiving IVC 5 days before surgery
non-DRCollect blood, aqueous humor, and initial vitreous at the time of surgery.patients with other retinopathy (idiopathic macular hole or epiretinal membrane)
IVC-3dayBlood and aqueous humor at the time of IVCpatients with proliferative diabetic retinopathy receiving IVC 3 days before surgery
IVC-5dayIVCpatients with proliferative diabetic retinopathy receiving IVC 5 days before surgery
IVC-6dayIVCpatients with proliferative diabetic retinopathy receiving IVC 6 days before surgery
IVC-6dayCollect blood, aqueous humor, and initial vitreous at the time of surgery.patients with proliferative diabetic retinopathy receiving IVC 6 days before surgery
IVC-7dayBlood and aqueous humor at the time of IVCpatients with proliferative diabetic retinopathy receiving IVC 7 days before surgery
IVC-shamCollect blood, aqueous humor, and initial vitreous at the time of surgery.patients with proliferative diabetic retinopathy receiving sham IVC
IVC-6dayBlood and aqueous humor at the time of IVCpatients with proliferative diabetic retinopathy receiving IVC 6 days before surgery
IVC-7dayIVCpatients with proliferative diabetic retinopathy receiving IVC 7 days before surgery
Primary Outcome Measures
NameTimeMethod
Changes of intraocular VEGF and PLGF of patients with proliferative diabetic retinopathy post-IVC (intravitreous injection of Conbercept).1-7 days
Secondary Outcome Measures
NameTimeMethod
Changes of intraocular and serum profibrotic cytokines in patients with proliferative diabetic retinopathy post-IVC.1-7 days
Effect of IVC on intraoperative complication of surgerySurgery day

Record the intraoperative complication: bleeding and iatrogenic retinal hole when surgically removing the proliferative membranes.

Effect of IVC on regression of neovascularization on vitreous fibrovascular membrane with optic coherence tomography angiography (OCTA)1 to 7 days

OCTA monitor the changes of neovascularization on vitreous fibrovascular membrane after IVC and before surgery

Changes of intraocular and serum inflammatory cytokines in patients with proliferative diabetic retinopathy post-IVC.1-7 days
Effect of IVC on surgery time of surgerySurgery day

surgery time of vitrectomy

Effect of IVC on postoperative complications1 to12 months

Record number of patient with vitreous re-bleeding and iris neovascularization postoperatively.

Changes of serum angiogenesis-related pro-cytokines in patients with proliferative diabetic retinopathy1-7 days
Vitreous concentration of Conbercept1-7 days

Detection of Vitreous concentration of the drug of Conbercept (Conbercept is a kind of fusion protein)

Effect of IVC on postoperative visual acuity1 to12 months

Best-corrected visual acuity postoperatively

Trial Locations

Locations (1)

First Affiliated Hospital of Nanjing Medical University

🇨🇳

Nanjing, Jiangsu, China

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