Cone Rescue in Retinitis Pigmentosa by the Treatment of Lycium Barbarum
Study Details
Study Description
Brief Summary
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.
| Condition or Disease | Intervention/Treatment | Phase |
|---|---|---|
|
N/A |
Detailed 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).
Study Design
Arms and Interventions
| Arm | Intervention/Treatment |
|---|---|
| Experimental: Lycium Barbarum Daily Lycium Barbarum dosage: 10g of granules for 12 months |
Dietary Supplement: Lycium Barbarum
Traditional Chinese Herbs
Other Names:
|
| Placebo Comparator: Placebo Placebo |
Dietary Supplement: Placebo
Placebo
|
Outcome Measures
Primary Outcome Measures
- ETDRS Visual Acuity (High Contrast) [12 months]
The high contrast visual acuity will be measured at the time point of baseline and 12 months. Visual acuity is to measure the eye's ability to resolve fine detail with full refractive error correction. The change of acuity (sec of arc) between 12-month time point and baseline will be provided to show the effect of interventions. The changes of the treatment group will be compared with the changes of the placebo group to illustrate the treatment effect of Lycium Barbarum.
Secondary Outcome Measures
- Visual Field Sensitivity [12 months]
Humphrey Visual Field Analyser will be used to measure the brightness sensitivity across the central 30 degree visual field at time point of baseline and 12 months. Visual field is to measure the size of the field of view and the sensitivity of the corresponding locations of the field of view. The change of sensitivity (dB) between 12-month time point and baseline will be provide to show the effects of interventions. The changes of the treatment group will be compared with the changes of the placebo group to illustrate the treatment effect of Lycium Barbarum
- Amplitudes of Flash Electroretinogram [12 months]
The cone responses from electroretinogram will be measured at the time point of baseline and 12 months. The cone response is related to the activity of the cone photoreceptor under light stimulation. The change of cone response b-wave amplitude (uV) between 12-month and baseline will be provided to show the effect of interventions. The b-wave amplitude is to measure the magnitude of electrical responses of cone cells in the retina. The changes of the treatment group will be compared with the changes of the placebo group to illustrate the treatment effect of Lycium Barbarum.
- Implicit Times of Flash Electroretinogram [12 months]
The cone responses from electroretinogram will be measured at the time point of baseline and 12 months. The cone response is related to the activity of the cone photoreceptor under light stimulation. The change of cone response b-wave implicit time (ms) between 12-month and baseline will be provided to show the effect of interventions. The b-wave implicit time is to measure the physiological changes of cone cells in the retina. The changes of the treatment group will be compared with the changes of the placebo group to illustrate the treatment effect of Lycium Barbarum.
Eligibility Criteria
Criteria
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
Contacts and Locations
Locations
| Site | City | State | Country | Postal Code | |
|---|---|---|---|---|---|
| 1 | The Hong Kong Polytechnic University | Hong Kong | Hong Kong |
Sponsors and Collaborators
- The Hong Kong Polytechnic University
- The University of Hong Kong
Investigators
- Principal Investigator: Henry HL Chan, PhD, The Hong Kong Polytechnic University
Study Documents (Full-Text)
None provided.More Information
Publications
None provided.- 01121876
Study Results
Participant Flow
| Recruitment Details | Recruited from a retinal disease patient association, Retina Hong Kong, and the Optometry Clinic at The Hong Kong Polytechnic University |
|---|---|
| Pre-assignment Detail | All the eligible subjects had the eye examination, including VA (ETDRS) charts, refractions, tonometry, external and internal ocular health assessments, fundus photo-documentation, Ganzfeld Electroretinogram, Humphrey Visual Field Analyser and Spectral-domain Optical Coherent Tomography |
| Arm/Group Title | Lycium Barbarum | Placebo |
|---|---|---|
| Arm/Group Description | Daily Lycium Barbarum dosage: 10g of granules for 12 months Lycium Barbarum: Traditional Chinese Herbs | Placebo Placebo: Placebo |
| Period Title: Overall Study | ||
| STARTED | 25 | 25 |
| COMPLETED | 23 | 19 |
| NOT COMPLETED | 2 | 6 |
Baseline Characteristics
| Arm/Group Title | Lycium Barbarum | Placebo | Total |
|---|---|---|---|
| Arm/Group Description | Daily Lycium Barbarum dosage: 10g of granules for 12 months Lycium Barbarum: Traditional Chinese Herbs | Placebo Placebo: Placebo | Total of all reporting groups |
| Overall Participants | 23 | 19 | 42 |
| Age (years) [Mean (Standard Deviation) ] | |||
| Mean (Standard Deviation) [years] |
50.4
(12.2)
|
48.4
(9.3)
|
49.4
(10.9)
|
| Sex: Female, Male (Count of Participants) | |||
| Female |
14
60.9%
|
14
73.7%
|
28
66.7%
|
| Male |
9
39.1%
|
5
26.3%
|
14
33.3%
|
| Region of Enrollment (participants) [Number] | |||
| Hong Kong |
23
100%
|
19
100%
|
42
100%
|
Outcome Measures
| Title | ETDRS Visual Acuity (High Contrast) |
|---|---|
| Description | The high contrast visual acuity will be measured at the time point of baseline and 12 months. Visual acuity is to measure the eye's ability to resolve fine detail with full refractive error correction. The change of acuity (sec of arc) between 12-month time point and baseline will be provided to show the effect of interventions. The changes of the treatment group will be compared with the changes of the placebo group to illustrate the treatment effect of Lycium Barbarum. |
| Time Frame | 12 months |
Outcome Measure Data
| Analysis Population Description |
|---|
| [Not Specified] |
| Arm/Group Title | Lycium Barbarum | Placebo |
|---|---|---|
| Arm/Group Description | Daily Lycium Barbarum dosage: 10g of granules for 12 months Lycium Barbarum: Traditional Chinese Herbs | Placebo Placebo: Placebo |
| Measure Participants | 23 | 19 |
| Mean (Standard Deviation) [log unit] |
-0.02
(0.09)
|
0.11
(0.17)
|
| Title | Visual Field Sensitivity |
|---|---|
| Description | Humphrey Visual Field Analyser will be used to measure the brightness sensitivity across the central 30 degree visual field at time point of baseline and 12 months. Visual field is to measure the size of the field of view and the sensitivity of the corresponding locations of the field of view. The change of sensitivity (dB) between 12-month time point and baseline will be provide to show the effects of interventions. The changes of the treatment group will be compared with the changes of the placebo group to illustrate the treatment effect of Lycium Barbarum |
| Time Frame | 12 months |
Outcome Measure Data
| Analysis Population Description |
|---|
| [Not Specified] |
| Arm/Group Title | Lycium Barbarum | Placebo |
|---|---|---|
| Arm/Group Description | Daily Lycium Barbarum dosage: 10g of granules for 12 months Lycium Barbarum: Traditional Chinese Herbs | Placebo Placebo: Placebo |
| Measure Participants | 23 | 19 |
| Mean (Standard Deviation) [dB] |
0.32
(2.93)
|
-0.16
(0.94)
|
| Title | Amplitudes of Flash Electroretinogram |
|---|---|
| Description | The cone responses from electroretinogram will be measured at the time point of baseline and 12 months. The cone response is related to the activity of the cone photoreceptor under light stimulation. The change of cone response b-wave amplitude (uV) between 12-month and baseline will be provided to show the effect of interventions. The b-wave amplitude is to measure the magnitude of electrical responses of cone cells in the retina. The changes of the treatment group will be compared with the changes of the placebo group to illustrate the treatment effect of Lycium Barbarum. |
| Time Frame | 12 months |
Outcome Measure Data
| Analysis Population Description |
|---|
| [Not Specified] |
| Arm/Group Title | Lycium Barbarum | Placebo |
|---|---|---|
| Arm/Group Description | Daily Lycium Barbarum dosage: 10g of granules for 12 months Lycium Barbarum: Traditional Chinese Herbs | Placebo Placebo: Placebo |
| Measure Participants | 23 | 19 |
| Mean (Standard Deviation) [uV] |
2.75
(9.17)
|
-4.00
(7.38)
|
| Title | Implicit Times of Flash Electroretinogram |
|---|---|
| Description | The cone responses from electroretinogram will be measured at the time point of baseline and 12 months. The cone response is related to the activity of the cone photoreceptor under light stimulation. The change of cone response b-wave implicit time (ms) between 12-month and baseline will be provided to show the effect of interventions. The b-wave implicit time is to measure the physiological changes of cone cells in the retina. The changes of the treatment group will be compared with the changes of the placebo group to illustrate the treatment effect of Lycium Barbarum. |
| Time Frame | 12 months |
Outcome Measure Data
| Analysis Population Description |
|---|
| [Not Specified] |
| Arm/Group Title | Lycium Barbarum | Placebo |
|---|---|---|
| Arm/Group Description | Daily Lycium Barbarum dosage: 10g of granules for 12 months Lycium Barbarum: Traditional Chinese Herbs | Placebo Placebo: Placebo |
| Measure Participants | 23 | 19 |
| Mean (Standard Deviation) [msec] |
-1.33
(5.03)
|
-1
(6.69)
|
Adverse Events
| Time Frame | 12 months | |||
|---|---|---|---|---|
| Adverse Event Reporting Description | Self reporting | |||
| Arm/Group Title | Lycium Barbarum | Placebo | ||
| Arm/Group Description | Daily Lycium Barbarum dosage: 10g of granules for 12 months Lycium Barbarum: Traditional Chinese Herbs | Placebo Placebo: Placebo | ||
All Cause Mortality |
||||
| Lycium Barbarum | Placebo | |||
| Affected / at Risk (%) | # Events | Affected / at Risk (%) | # Events | |
| Total | 0/23 (0%) | 0/19 (0%) | ||
Serious Adverse Events |
||||
| Lycium Barbarum | Placebo | |||
| Affected / at Risk (%) | # Events | Affected / at Risk (%) | # Events | |
| Total | 0/23 (0%) | 0/19 (0%) | ||
Other (Not Including Serious) Adverse Events |
||||
| Lycium Barbarum | Placebo | |||
| Affected / at Risk (%) | # Events | Affected / at Risk (%) | # Events | |
| Total | 0/23 (0%) | 0/19 (0%) | ||
Limitations/Caveats
More Information
Certain Agreements
Principal Investigators are NOT employed by the organization sponsoring the study.
There is NOT an agreement between Principal Investigators and the Sponsor (or its agents) that restricts the PI's rights to discuss or publish trial results after the trial is completed.
Results Point of Contact
| Name/Title | Dr. Henry Chan |
|---|---|
| Organization | Hong Kong Polytechnic University |
| Phone | 85227667937 |
| henryhl.chan@polyu.edu.hk |
- 01121876