Cone Rescue in Retinitis Pigmentosa by the Treatment of Lycium Barbarum

The Hong Kong Polytechnic University

Status

Completed

Conditions

Retinitis Pigmentosa

Treatments

Dietary Supplement: Lycium Barbarum

Dietary Supplement: Placebo

Study type

Interventional

Funder types

Other

Identifiers

NCT02244996

01121876

Details and patient eligibility

About

Objectives: To study the immediate effect and the persistent effect of Lycium barbarum (LB) treatment on retinal functions, especially the cone function, and retinal structure in patients with retinitis pigmentosa (RP) Design: Randomised controlled double-masked trial

Setting: Primary Care clinical trial

Participants: 120 RP subjects will be recruited from Ophthalmology department at The University of Hong Kong and the Retina Hong Kong. Interventions: Subjects will be randomly allocated to LB (treated with LB granules) or control (treated with placebo) groups for 1 year. After the 1st year, both groups will stop the treatment and all subjects will also have the same eye exam in 6-month period for the 2nd year.

Main outcome measures: The primary outcome is the total sensitivity scores of 30-2 & 60-4 programmes of Humphrey Visual Field Analysis (HVFA). The secondary outcomes are the b-wave amplitudes of Full-field Electroretinogram (ffERG) responses, the amplitudes of direct component and induced component of Multifocal Electroretinogram (mfERG), and the ETDRS visual acuity.

Full description

The study was a randomized controlled trial with a double-masked, placebo-controlled design. All the subjects were randomly allocated into either LB (treatment) group or placebo (control) group.

All the eligible subjects had the eye examination, including VA using the Early Treatment of Diabetic Retinopathy Study (ETDRS) chart, refractions, tonometry, external and internal ocular health assessments, and fundus photo-documentation. Three additional tests were conducted to investigate the functional and structural changes in the RP patients, including Ganzfeld Electroretinogram, Humphrey Visual Field Analyser (Zeiss, Dublin, USA) and Spectral-domain Optical Coherent Tomography (SD-OCT) (Heidelberg Engineering, USA).

Enrollment

50 patients

Sex

All

Ages

18 to 70 years old

Volunteers

No Healthy Volunteers

Inclusion criteria

Ocular conditions:

Retinitis pigmentosa;
best corrected VA LogMAR 0.20 or better;
Humphrey Visual Field Analysis (HVFA) 30-2 total mean defect > or = 250 Decibel;
Intra-ocular pressure (IOP) <21 mmHg;
van Herrick ratio < or = 0.5;
no other ocular diseases

Dietary conditions:

Fruit and vegetable intake <10 servings/day;
spinach or kale intake < or = serving/day;
dietary lutein intake < or = 5.4mg/day;
no intake of cod liver oil or omega-3 capsules;
dietary Lycium barbarum intake < or =10 fruits/week;
supplement intake < or = 5000 IU/day of Vit. A and < or = 30 IU/day of Vit. E;
alcoholic consumption < or = 3 beverages/day

Exclusion criteria

BMI > 40;
intake of any anticoagulants (especially Warfarin),
pregnant or planning to be pregnant;
smoking;
other clinically significant systemic diseases, eg. diabetes, liver disease and heart disease