Clinical trial NCT04283162: Using Calcium Dobesilate to Treat Chinese Patients With Mild to Moderate Non-proliferative Diabetic Retinopathy
Official title: Efficacy of Calcium Dobesilate in Treating Chinese Patients With Mild to Moderate Non-proliferative Diabetic Retinopathy (CALM-DR): a Single-blind, Multicenter, Cluster-randomized, Controlled Trial
Study type: INTERVENTIONAL
Overall status: UNKNOWN
Phase: PHASE4
Conditions: Diabetic Retinopathy
Keywords: calcium dobesilate
mild to moderate non-proliferative diabetic retinopathy
cluster-randomized controlled trial
Lead sponsor: Zhongda Hospital
Sponsor class: OTHER
First posted: 2020-02-25
Enrollment: 1200
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: TREATMENT

Brief summary: Calcium dobesilate has been recommended to treat diabetic retinopathy due to its potential in protecting against retinal vascular damage. However, there was limited evidence exploring its efficacy in combating diabetic retinopathy progression. This study, a single-blind, multicenter, cluster-randomized, controlled superiority trial, was designed to evaluate whether calcium dobesilate could prevent diabetic retinopathy progression into an advanced stage among Chinese patients with mild to moderate non-proliferative diabetic retinopathy.

Detailed description: A total of 1,200 patients with mild to moderate non-proliferative diabetic retinopathy will be enrolled and randomly assigned at a ratio of 1:1 into the control group (that is, conventional treatment group) and the intervention group (that is, conventional treatment plus calcium dobesilate \[500 mg, 3 times per day\] for 12 months). The severity of diabetic retinopathy will be assessed by the Early Treatment Diabetic Retinopathy Study scale.

Eligibility criteria: Inclusion Criteria:

* Being diagnosed with mild to moderate diabetic retinopathy
* Being older than 18 years
* Being willing to attend this trial.

Exclusion Criteria:

* Being allergic hypersensitive to experimental drugs or comparator drugs
* Having alanine aminotransferase or aspartate aminotransferase ≥2 times higher than the upper limit of normal value, or total bilirubin ≥1.5 times higher than the upper limit of normal value upon the exclusion of mild fatty liver disease
* Having severe renal insufficiency (defined as an estimated glomerular filtration rate ≤30 mL/min/1.73 m\^2)
* Having malignant tumor and some other life-threatening diseases
* Being in pregnancy, expecting pregnancy, or breast feeding
* Being with unstable conditions, such as: uncontrolled high blood pressure (e.g., blood pressure \>180/100 mmHg); hemoglobin A1c \>8.0% or uncontrolled high blood glucose or hypoglycemia; acute cardiovascular events like unstable angina, congestive heart failure, stroke, transient ischemic attack, or myocardial infarction within the previous 3 months; uncontrolled infection; and diabetic ketoacidosis or hyperosmolar state in the past 1 month
* Being with glaucoma, cataracts, or other opacities that may interfere with retinal examination and fundus photography
* Receiving laser treatment, cryo-coagulation, or vitrectomy
* Taking drugs such as diabetic retinopathy or traditional Chinese medicine that may help to improve micro-vascular function in the past 2 weeks
* Receiving vascular endothelial growth factor therapy in the past 4 months or will be judged to take vascular endothelial growth factor therapy because of disease progression
* Having attended other clinical trials in the past 1 month, being attending some clinical trials, or some other conditions that were judged unfit for this trial by investigators

Primary outcomes:
measure: The rate of the progression of diabetic retinopathy
timeFrame: from baseline to the end of treatment (12 months later)
Secondary outcomes:
measure: Changes in eyesight
timeFrame: 3-month, 6-month, and 12-month from baseline
measure: Changes in the numbers, location, and types of the retinal lesions
timeFrame: 3-month, 6-month, and 12-month from baseline
measure: Changes in the retinal blood vessel diameter and arteriovenous ratio
timeFrame: 3-month, 6-month, and 12-month from baseline
measure: Changes in metabolic biomarkers such as HbA1c
timeFrame: 3-month, 6-month, and 12-month from baseline
Other outcomes:
Locations:
city: Nanjing
country: China
facility: Department of Endocrinology, Zhongda Hospital, Institute of Diabetes, Southeast University
state: Jiangsu
Study officials:
affiliation: Zhongda Hospital
name: Zilin Sun, Ph.D.
role: PRINCIPAL_INVESTIGATOR
References:
citation: Hu H, Liu J, Wang D, Qiu S, Yuan Y, Wang F, Wen L, Song Q, Sun ZL. Efficacy of calcium dobesilate in treating Chinese patients with mild-to-moderate non-proliferative diabetic retinopathy (CALM-DR): protocol for a single-blind, multicentre, 24-armed cluster-randomised, controlled trial. BMJ Open. 2021 May 28;11(5):e045256. doi: 10.1136/bmjopen-2020-045256.