Intravitreal Bevacizumab for Nonproliferative Diabetic Retinopathy

Study Overview
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Brief Summary
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In this randomized clinical trial, 100 eyes with nonproliferative diabetic retinopathy will be included and divided randomly into 2 groups: Intravitreal Bevacizumab group (50 eyes) that receive 6 bimonthly intravitreal bevacizumab, and control group (50 eyes) that undergo regular follow-up for Diabetic Retinopathy. Diabetic macular edema (DME) will be treated independently in all groups by intravitreal bevacizumab. Primary outcome will be the percentage of patients with progression of 2 or more stages through international diabetic retinopathy staging. The secondary measures will be changes in best corrected visual acuity (BCVA) and central macular thickness (CMT), and number of examinations and injection.

Official Title
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Efficacy and Safety of Intravitreal Bevacizumab for the Improvement of Severe Non-proliferative Diabetic Retinopathy Without DME: a Randomized Clinical Trial

Conditions
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Non-proliferative Diabetic Retinopathy

Intervention / Treatment
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* Drug: Intravitreal Bevacizumab IVB
* Other: Follow-up with regular examination for determination of DR progression


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Presence of severe NPDR with DRSS score more than 53 with or without diabetic macular edema Diagnosis of DM (type 1 or 2) with age more than 18 years' old Visual acuity from 20/25 to 20/40 according to Snellen chart examination or more than 69 letters according to ETDRS chart Exclusion Criteria: Presence of proliferative diabetic retinopathy features including vitreous hemorrhage or optic disc or retinal neovascularization History of retinal laser photocoagulation Tractional retinal detachment involving the macula Evidence of neovascularization of angle on examination Macular edema due to a cause other than DME Any ocular condition which may change visual acuity during the study History of intravitreal injection of anti-vascular endothelial growth factor agent in past 3 months History of any use of intravitreal corticosteroid History of major intra-ocular surgery except cataract surgery in the past 6 months History of thromboembolic every in the past 3 months

Ages Eligible for Study
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Minimum Age: 18 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: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Intravitreal Bevacizumab IVB group<br> | Drug: Intravitreal Bevacizumab IVB<br>* Intravitreal Bevacizumab IVB group (50 eyes) that receive 6 bimonthly IVBs within a period of 10 months following the enrollment<br>|
| Sham Comparator: undergo regular follow-up for Diabetic Retinopathy<br> | Other: Follow-up with regular examination for determination of DR progression<br>* regular examination for determination of DR progression<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Percentage of patients with equal or more than 2 stages of progression in diabetic retinopathy staging | Multiple fundus photographs interpreted by a single vitreoretinal surgeon who is blind to the study groups | 12 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Best corrected visual acuity | Best corrected visual acuity based on ETDRS letter scale and logMAR | 12 months | 
| Central retinal thickness | Central retinal thickness according to macular ocular coherence tomography | 12 months | 
| Number of visits | Number of visits in each time point | 12 months |