Evaluation of Doxycycline Verses Placebo for the Treatment of Severe Nonproliferative or Mild or Moderate Proliferative Diabetic Retinopathy

Study Overview
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Brief Summary
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This 24 month randomized research study will evaluate whether doxycycline can 1) slow the deterioration or improve retinal function and/or 2) induce regression, or slow progression, of diabetic retinopathy in participants over 18 years of age with type 1 or type 2 diabetes with severe non-proliferative or early proliferative diabetic retinopathy.

Detailed Description
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The objectives of this proof-of-concept study are to investigate whether doxycycline can 1) slow the deterioration or improve retinal function and/or 2) induce regression, or slow progression, of diabetic retinopathy. The tests will be performed in the Ophthalmology Departments of the Penn State College of Medicine and Glostrup Hospital, Copenhagen, Denmark. The 24 month proof-of-concept clinical study will involve a prospective, randomized, double-masked clinical trial including 60 adult patients with type 1 or type 2 diabetes who have severe non-proliferative diabetic retinopathy (ETDRS level 53E) or mild or moderate proliferative diabetic retinopathy (retinal and /or optic disk neovascularization less than the high-risk ETDRS level 61 or 65), neovascularization of the disc or neovascularization elsewhere >1/2 disc area and in whom panretinal photocoagulation is not imminently required in the ophthalmologist's judgment. Systemic Exclusion Criteria: unstable medical status (e.g. glycemic control, blood pressure, cardiovascular disease) in the opinion of investigator significant renal disease (defined as a serum creatinine > 2.5 mg/dL), systolic blood pressure > 180 mm Hg or diastolic blood pressure > 110 mm Hg history of headaches associated with tetracycline therapy history of pseudotumor cerebri pregnancy; for women of child-bearing potential, a serum pregnancy test will be performed. lactating or intending to become pregnant during the study period (at least 24 months) sexually active women of child-bearing potential not actively practicing birth control by using a medically accepted device or therapy (that is, intrauterine device, hormonal contraceptive, or barrier devices) during the study period (at least 24 months); since doxycycline may interfere with the effectiveness of hormonal contraceptives, sexually active women of child-bearing potential who use a hormonal contraceptive will be required to use a second form of contraception to safeguard against contraceptive failure while participating in the study known allergy/intolerance to doxycycline or any ingredient in the study drug or placebo (e.g. cellulose, hypromellose, iron oxide, methacrylic acid copolymer, polyethylene glycol, polysorbate 80, sugar spheres, talc, titanium dioxide, and triethyl citrate) patients taking phenytoin, barbiturates or carbamazepine, with gastroparesis, with a history of gastrectomy, gastric bypass surgery or otherwise deemed achlorhydric or with a BMI > 30 kg/m2 will also be excluded because of altered doxycycline pharmacokinetics and/or bioavailability patients taking strontium, acitretin or tretinoin will be excluded due to the potential for serious drug interactions with doxycycline patients with abnormal ALT or AST at baseline will be referred to their primary care physician for medical clearance for participation in this study

Official Title
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Evaluation of Effect of Doxycycline Verses Placebo on Diabetic Retinopathy Progression and Retinal Function in Patients With Severe Non-proliferative or Mild or Moderate (Non-high-risk) Proliferative Diabetic Retinopathy

Conditions
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Diabetic Retinopathy

Intervention / Treatment
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* Drug: doxycycline monohydrate
* Drug: placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: age ≥ 18 years old diagnosis of type 1 or type 2 diabetes mellitus have a hemoglobin A1c less than 11% at pre-qualification visit able and willing to give informed consent best-corrected ETDRS visual acuity in study eye ≥ 49 letters (20/100) severe non-proliferative diabetic retinopathy (ETDRS level 53E) or retinal and/or optic disk neovascularization less than the high-risk characteristics defined by the Diabetic Retinopathy Study (ETDRS level61- 65), and in whom panretinal photocoagulation is not imminently required in the ophthalmologist's judgment able to perform reliable visual field and dark adaptation testing central subfield thickness on OCT of ≤ 275microns foveal fixation present in each eye (assessed by fundus photography using an internal fixation pointer or assessed by the investigator) media clarity and pupil dilation sufficient for high-quality fundus photographs and fluorescein angiograms Exclusion Criteria: high-risk neovascularization in study eye prior panretinal photocoagulation in the study eye focal/grid laser photocoagulation in the macula within the past 15 weeks in the study eye intraocular pressure > 22mmHg by Goldmann Tonometry in the study eye history of pars plana vitrectomy in the study eye vitreous or pre-retinal hemorrhage in the study eye systemic or intravitreal anti-VEGF agent to the study eye or the fellow eye within the past 3 months peribulbar steroid injection to the study eye or the fellow eye within the past 6 months intravitreal triamcinolone acetonide to the study eye within the past 4 months expectation by the investigator that retinal photocoagulation or other treatment for diabetic retinopathy (e.g. focal/grid laser to study eye, intravitreal triamcinolone acetonide to study eye, intravitreal anti-VEGF agent to study or fellow eye, ruboxistaurin or systemic anti-VEGF agent for diabetic macular edema) will be administered in the subsequent 24 months an ocular condition (other than diabetes) is present in the study eye that, in the opinion of the investigator, might alter visual acuity during the course of the study (e.g. retinal vein occlusion, uveitis or other ocular inflammatory disease, neovascular glaucoma, Irvine-Gass Syndrome, etc) anticipated need for cataract surgery in the study eye in the subsequent 24 months in the opinion of the investigator history of major ocular surgery (including cataract surgery, scleral buckle, any intraocular surgery, etc) in the study eye within prior 6 months or anticipated within the subsequent 24 months following randomization aphakia in the study eye history of YAG capsulotomy performed in the study eye within 2 months prior to randomization

Ages Eligible for Study
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Minimum Age: 18 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 |
| --- | --- |
| Experimental: Doxycycline Monohydrate<br>stratified equally to doxycycline monohydrate 50mg taken once daily for 24 months | Drug: doxycycline monohydrate<br>* 50mg once daily for 24 months<br>* Other names: doxycycline;|
| Placebo Comparator: Placebo<br>stratified equally to placebo taken once daily for 24 months | Drug: placebo<br>* placebo taken once daily for 24 months<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Dark Adaptation, Rod Intercept | Change in dark adaptation is measured as dark adaptation time at baseline measured in minutes minus dark adaptation time measured at 24 months | Baseline and 24 months | 
| Change in Photopic Visual Field | Change in photopic visual fields between baseline and 24 months | Baseline and 24 months | 
| Change in Frequency Doubling Perimetry (FDP) | Change in Frequency Doubling Perimetry (FDP) from baseline, shown as mean and foveal (center of retina) scores | 24 months | 
| Change in Early Treatment Diabetic Retinopathy Study (ETDRS) | Change in ETDRS visual acuity letter score from baseline. ETDRS is measured on a scale of 0 to 70 where 0 means inability to see anything on the chart and 70 is normal (20/20) acuity. | Baseline and 24 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Central Subfield Thickness | Change in central subfield thickness from baseline | Baseline and 24 months | 
| Change in Macular Volume | Change in macular volume from baseline | 24 months | 
| Change in Central Retinal Artery Equivalent (CRAE) Diameter | Change in Central Retinal Artery Equivalent (CRAE) diameter from baseline | 24 months | 
| Change in Central Retinal Vein Equivalent (CRVE) Diameter | Change in Central Retinal Vein Equivalent (CRVE) diameter from baseline | 24 months | 
| Change in Arteriovenous Ratio Diameter | Change in arteriovenous ratio diameter from baseline | 24 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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diabetic retinopathy, diabetes, diabetic eye studies, neovascularization