None listed
Conditions
Brief summary
This project aims to translate into the clinic a recently published study, demonstrating the protective role of vitamin B3 supplements (nicotinamide) in a mouse model of glaucoma. Glaucoma causes progressive loss of nerve tissue in the eye, and irreversible vision loss. This study investigates the short-term effect of taking nicotinamide supplements on the eye’s structure and function compared to placebo. Primary aims of this study include: 1) determining whether nicotinamide supplements in participants with glaucoma leads to short-term improvement in visual function measured using visual fields and the electroretinogram (ERG) and 2) determining whether nicotinamide leads to structural changes to the nerve tissue, imaged using hyperspectral imaging and optical coherence tomography. Participants diagnosed with glaucoma by an ophthalmologist will be invited to undertake the 24-week study with crossover design. They will be randomly assigned to take nicotinamide or placebo daily for 12 weeks. The ERG, visual fields and imaging are performed at baseline, 6 and 12-weeks post-intervention. Participants then crossover to take placebo or nicotinamide for another 12 weeks and the same measurements are repeated at 6 and 12-weeks post-intervention.
Interventions
International Nonproprietary Name (INN): nicotinamide
Intervention: daily nicotinamide supplementation for 12 weeks
Dose: accelerated dose from 1.5 grams daily for 6 weeks to 3 grams daily for 6 weeks
Mode of administration: oral tablet
Study design: 2 participant groups with cross-over study design. Participants are randomly assigned to receive either nicotinamide or placebo for 12 weeks, followed by a cross-over (i.e. those on nicotinamide first will switch to placebo and those on placebo fi
International Nonproprietary Name (INN): nicotinamide Intervention: daily nicotinamide supplementation for 12 weeks Dose: accelerated dose from 1.5 grams daily for 6 weeks to 3 grams daily for 6 weeks Mode of administration: oral tablet Study design: 2 participant groups with cross-over study design. Participants are randomly assigned to receive either nicotinamide or placebo for 12 weeks, followed by a cross-over (i.e. those on nicotinamide first will switch to placebo and those on placebo first will switch to nicotinamide) for a further 12 weeks. A washout period will not be utilised as the effect of nicotinamide does not have a persistent effect after intake is ceased. As participants will be seen in 6-weekly intervals, we do not expect a nicotinamide-induced effect on our measurements in the group that receives nicotinamide first and placebo second. As for those that receive placebo first, then a washout period is also unnecessary as no intervention has been given. Adherence monitoring: remaining tablets will be counted at each visit, participants will be asked to log each time they forget a dose. To improve adherence, weekly reminders via phone, e-mail or text message will be sent, and a daily alarm set on participant's phone (if they have a smartphone). A minimum 70% compliance rate will be deemed acceptable, which approximately equates to forgetting to take the intervention twice a week.
Sponsors
Centre for Eye Research Australia
Study design
Allocation
Randomised controlled trial
Intervention model
Crossover
Primary purpose
Treatment
Masking
Blinded (masking used) (Subject, Investigator)
Eligibility
Sex/Gender
All
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
- Diagnosis of primary open angle glaucoma by an ophthalmologist - Recent (last 6 months), reliable visual field with mean defect equal to or better than -6 dB
Exclusion criteria
- those who are currently or intending to be pregnant/breastfeeding during the study - those unwilling to abstain from other vitamin B supplements during the study period - history of severe allergies or allergic reaction to nicotinamide or niacin - those diagnosed with cancer in the last 5 years (except treated basal or squamous cell carcinoma) - those with a history of liver disease - those who cannot commit to the follow-up visits which occur at 6-weekly intervals over 24 weeks - those who cannot provide informed consent - eyes with a history of intraocular surgery in the past 6 months (uncomplicated cataract surgery within the last 3 months) - systemic/ocular disease that are known to affect retinal function (e.g. age-related macular degeneration, demyelinating diseases, diabetic retinopathy)
Outcome results
None listed