Saponins for macular disease

Oral glycoside supplement (triterpenoid saponins) for early and intermediate stage age-related macular degeneration: an exploratory randomised placebo-controlled trial

Status

Active, not recruiting

Phases

Phase 2

Study type

Interventional

Source

ISRCTN

Registry ID

ISRCTN82949875

Enrollment

Registered

2024-04-02

Start date

2025-04-01

Completion date

Unknown

Last updated

2026-02-16

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Men and women with early or intermediate stage age-related macular degeneration (AMD) in the trial eye and any stage of AMD in the non-trial eye Eye Diseases

Interventions

Randomisation will take place at baseline visit 2 (up to 3 weeks after baseline visit 1) when eligibility has been confirmed. Randomisation will be by blocked randomisation stratified by site and age

Eligibility

Sex/Gender

All

Age

60 Years to 85 Years

Inclusion criteria

Inclusion criteria: Current participant inclusion criteria as of 25/07/2024: 1. Aged 60 to 85 years old (inclusive) 2. Able to provide informed consent and comply with the trial visit schedule 3. AMD in both eyes (of any stage) 4. Early or intermediate stage AMD (Beckman classification) in at least one eye Previous participant inclusion criteria: 1. Aged 55 to 85 years old (inclusive) 2. Able to provide informed consent and comply with the trial visit schedule 3. AMD in both eyes (of any stage) 4. Early or intermediate stage AMD (Beckman classification) in at least one eye

Exclusion criteria

Exclusion criteria: Current participant exclusion criteria as of 25/07/2024: 1. Ocular pathology in the study eye (or in either eye for genetic conditions or glaucoma), other than age-related macular degeneration, which may affect visual function 2. Intraocular pressure of 24 mmHg or greater 3. Grade <2 van Herick or history of allergic reaction to dilating eye drops 4. Unable to classify AMD grade 5. Lens opacity greater than grade 2 on any Lens Opacities Classification System III (LOCS III) criterion, or other media opacity/nystagmus that might interfere with quality retinal imaging 6. Diabetes 7. Vitamin A deficiency 8. Other significant systemic disease or medication known to affect visual or retinal function 9. Systemic illness that would compromise participation in a 1-year trial 10. Actively under treatment for cancer 11. Diagnosed with cancer with ocular involvement 12. Insufficient English language comprehension 13. A possible cognitive impairment as determined using an abridged Mini-Cog. This is defined as a score of less than 3. 14. Known or suspected seafood allergy 15. Photosensitive epilepsy 16. Currently treated with warfarin or other vitamin K antagonist 17. Participation in any other interventional trial within 30 days prior to entering this trial 18. Men who are planning a pregnancy with their partner or have partners who are women of childbearing potential 19. Taking supplements containing saponins (e.g. ginseng) 20. Unable to consume the IMP or placebo for a period of longer than 24 hours during the treatment window (for example a prolonged fast or repeated 24-hour fast) 21. Participants undergoing planned, forthcoming major surgical interventions Previous participant exclusion criteria: 1. Ocular pathology in the study eye (or in either eye for genetic conditions or glaucoma), other than age-related macular degeneration, which may affect visual function 2. Intraocular pressure of 24 mmHg or greater 3. Grade <2 van Herick or history of allergic reaction to dilating eye drops 4. Unable to classify AMD grade 5. Lens opacity greater than grade 2 on any Lens Opacities Classification System III (LOCS III) criterion, or other media opacity/nystagmus that might interfere with quality retinal imaging 6. Diabetes 7. Vitamin A deficiency 8. Other significant systemic disease or medication known to affect visual or retinal function 9. Systemic illness that would compromise participation in a 1-year trial 10. Actively under treatment for cancer 11. Diagnosed with cancer with ocular involvement 12. Insufficient English language comprehension 13. A possible cognitive impairment as determined using an abridged Mini-Cog. This is defined as a score of less than 3. 14. Known or suspected seafood allergy 15. Photosensitive epilepsy 16. Currently treated with warfarin or other vitamin K antagonist 17. Participation in any other interventional trial within 30 days prior to entering this trial 18. Women who are pregnant, lactating or planning a pregnancy, or men who have a partner who is planning a pregnancy 19. Taking supplements containing saponins (e.g. ginseng) 20. Unable to consume the IMP or placebo for a period of longer than 24 hours during the treatment window (for example a prolonged fast or repeated 24-hour fast) 21. Participants undergoing planned, forthcoming major surgical interventions

Design outcomes

Primary

Measure	Time frame
The feasibility of a subsequent fully powered trial, assessed using: 1. Recruitment: the proportion of those contacted who are randomised will be tabulated to give an idea of the feasibility of recruitment into a trial in this population 2. Retention: to assess retention over 4 and 12 months. Participants will be contacted by the researchers monthly during the 4-month treatment period. Participants will be sent reminders prior to their 4- and 12-month appointments. The proportion of those randomised who provide complete follow-up clinical data at each timepoint by arm will be tabulated. 3. Adherence to treatment. Participants will be given a tablet diary to complete over the 4-month treatment period (from baseline) and will receive monthly ‘compliance’ phone calls from the researchers to be ‘reminded’ to take their medication. The diary will be returned at 4 months, visit 1. The proportion of participants who adhered to the treatment regimen will be tabulated. The proportion of tablets taken per patient will also be tabulated by arm, assessed from tablet counts. 4. Acceptability of the intervention: an end-of-trial participant questionnaire at 12 months, visit 1, to assess the acceptability of the IMP and trial procedures and for participants to be able to speak about their experiences whilst taking part in the trial 5. Feasibility of the eligibility assessment process: the proportion of participants with all required information to determine eligibility from baseline visit 1 to baseline visit 2: the time taken and the percentage of people who the researchers think are eligible, i.e. who complete baseline visit 1, but who are, on the basis of GP feedback, later ruled out from baseline visit 2 and the study 6. Feasibility of collecting the outcome data: levels of data completeness will be tabulated for each follow-up timepoint for each outcome measure with confidence intervals by arm 7. Serious adverse events (SAEs) including comparative rates between arms. The num	—

Measure

Time frame

The feasibility of a subsequent fully powered trial, assessed using: 1. Recruitment: the proportion of those contacted who are randomised will be tabulated to give an idea of the feasibility of recruitment into a trial in this population 2. Retention: to assess retention over 4 and 12 months. Participants will be contacted by the researchers monthly during the 4-month treatment period. Participants will be sent reminders prior to their 4- and 12-month appointments. The proportion of those randomised who provide complete follow-up clinical data at each timepoint by arm will be tabulated. 3. Adherence to treatment. Participants will be given a tablet diary to complete over the 4-month treatment period (from baseline) and will receive monthly ‘compliance’ phone calls from the researchers to be ‘reminded’ to take their medication. The diary will be returned at 4 months, visit 1. The proportion of participants who adhered to the treatment regimen will be tabulated. The proportion of tablets taken per patient will also be tabulated by arm, assessed from tablet counts. 4. Acceptability of the intervention: an end-of-trial participant questionnaire at 12 months, visit 1, to assess the acceptability of the IMP and trial procedures and for participants to be able to speak about their experiences whilst taking part in the trial 5. Feasibility of the eligibility assessment process: the proportion of participants with all required information to determine eligibility from baseline visit 1 to baseline visit 2: the time taken and the percentage of people who the researchers think are eligible, i.e. who complete baseline visit 1, but who are, on the basis of GP feedback, later ruled out from baseline visit 2 and the study 6. Feasibility of collecting the outcome data: levels of data completeness will be tabulated for each follow-up timepoint for each outcome measure with confidence intervals by arm 7. Serious adverse events (SAEs) including comparative rates between arms. The num

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Secondary

Measure	Time frame
Measured at baseline, 4 and 12 months: 1. Dark adaptation with calculation of cone tau(s), rod cone break time (s) and the slope of the S2 component of the rod dark adaptation function (log cdm-2 per s) 2. Visual acuity measured using a standard Early Treatment Diabetic Retinopathy Study (ETDRS) test in both eyes and binocularly with their distance refractive error in place (number of letters) 3. Contrast sensitivity measured using a Pelli Robson letter chart in both eyes and binocularly with participant’s habitual distance refractive error in place 4. Patient-reported outcome measure (PROM) (Low Luminance Questionnaire) score 5. International Society for Clinical Electrophysiology of Vision (ISCEV) electrophysiology protocol recorded using an Espion E3 Electroretinography System. The standard ISCEV ERG protocol for both eyes includes the following individual tests: dark-adapted 0.01 ERG; dark-adapted 3 ERG; dark-adapted 10 ERG; light-adapted 3.0 ERG; light-adapted 30 Hz flicker ERG. The parameters (amplitudes and implicit times) for each test will be calculated. 6. Beckman AMD clinical grading based on colour fundus photography of the posterior pole from both eyes (45° photographs) and augmented by evaluation of optical coherence tomography macular images (20° x 20°) 7. Retinal and intra-retinal layer thickness derived from automated segmentation of optical coherence tomography macular images (20° x 20°) 8. Near infra-red confocal scanning laser ophthalmoscopy (NIR cSLO) and optical coherence tomography macular images obtained using a Heidelberg Spectralis and colour retinal photography to provide a visual record of ocular/retinal health and assess eligibility	—

Measure

Time frame

Measured at baseline, 4 and 12 months: 1. Dark adaptation with calculation of cone tau(s), rod cone break time (s) and the slope of the S2 component of the rod dark adaptation function (log cdm-2 per s) 2. Visual acuity measured using a standard Early Treatment Diabetic Retinopathy Study (ETDRS) test in both eyes and binocularly with their distance refractive error in place (number of letters) 3. Contrast sensitivity measured using a Pelli Robson letter chart in both eyes and binocularly with participant’s habitual distance refractive error in place 4. Patient-reported outcome measure (PROM) (Low Luminance Questionnaire) score 5. International Society for Clinical Electrophysiology of Vision (ISCEV) electrophysiology protocol recorded using an Espion E3 Electroretinography System. The standard ISCEV ERG protocol for both eyes includes the following individual tests: dark-adapted 0.01 ERG; dark-adapted 3 ERG; dark-adapted 10 ERG; light-adapted 3.0 ERG; light-adapted 30 Hz flicker ERG. The parameters (amplitudes and implicit times) for each test will be calculated. 6. Beckman AMD clinical grading based on colour fundus photography of the posterior pole from both eyes (45° photographs) and augmented by evaluation of optical coherence tomography macular images (20° x 20°) 7. Retinal and intra-retinal layer thickness derived from automated segmentation of optical coherence tomography macular images (20° x 20°) 8. Near infra-red confocal scanning laser ophthalmoscopy (NIR cSLO) and optical coherence tomography macular images obtained using a Heidelberg Spectralis and colour retinal photography to provide a visual record of ocular/retinal health and assess eligibility

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Countries

England, United Kingdom, Wales

Contacts

Public ContactJoanna Smith

SAMADI@cardiff.ac.uk+44 (0)29 20 687 904

Outcome results

None listed

Source: ISRCTN (via WHO ICTRP) · Data processed: Aug 22, 2026