Apply to Trial

Compensation: Varies

Number of Visits: 8

Duration: 3.5 years

180 Participants Needed

High-Dose Vitamin D for Preventing Dementia

Overseen ByHongzheng Zhang

Age: 65+

Sex: Any

Trial Phase: Phase 2

Sponsor: University of California, Davis

Must not be taking: Benzodiazepines, Antipsychotics, Narcotics, others

Disqualifiers: Hepatic insufficiency, Renal insufficiency, Hypercalcemia, others

No Placebo GroupAll trial participants will receive the active study treatment (no placebo)

Prior Safety DataThis treatment has passed at least one previous human trial

Approved in 6 JurisdictionsThis treatment is already approved in other countries

What You Need to Know Before You Apply

What is the purpose of this trial?

This Phase II randomized clinical trial aims to test if supplementation with high dose oral vitamin D will successfully correct vitamin D insufficiency, compared to treatment with standard (RDA) dose vitamin D in a diverse community-based elderly cohort. The effect of high-dose vs. standard-dose vitamin D on altering cognitive trajectories will also be assessed and data will be expected to be used in designing a potential definitive Phase III trial in elderly groups at risk for dementia. A total of 180 elderly persons with longitudinal biomarkers, neuropsychological testing and brain MRI scans will be enrolled, with 152 (\~50 with MCI, 50 with mild AD and 50 with no cognitive impairment) expected to complete the 3½-year study. One-half of each diagnostic group will be randomized to treatment with high-dose vitamin D3 (4,000 IU daily) or to standard dose Vitamin D (600 IU capsule daily + \~200 IU dietary = \~800 IU total/day). Longitudinal MRI analyses will provide an estimate of the treatment effect size on brain atrophy rate. Vitamin D receptor genotype polymorphisms and their impact on response to oral supplementation will also be examined. If vitamin D supplementation improves cognitive outcome, this could have a large impact on the public health, since low vitamin D status is a common, readably treatable condition which may provide a novel window to prevent dementia and AD. Furthermore, the higher prevalence of AD and dementia in African Americans and Latinos could be partially attributable to vitamin D insufficiency.

Will I have to stop taking my current medications?

The trial does not specify if you need to stop taking your current medications, but it does mention that stable doses of certain medications like SSRIs or SNRIs are allowed. If you are taking vitamin D supplements, you should continue with the same dose throughout the study.

Is high-dose Vitamin D generally safe for humans?

Research on high-dose Vitamin D, also known as Vitamin D3 or Cholecalciferol, has not specifically highlighted safety concerns in humans, but it is important to consult with a healthcare provider before starting any high-dose supplementation.¹ ² ³ ⁴ ⁵

How does high-dose Vitamin D3 differ from other treatments for preventing dementia?

High-dose Vitamin D3 is unique because it is being studied for its potential neuroprotective effects, possibly through mechanisms like vasoprotection and amyloid clearance, which are not typical of standard dementia treatments. Unlike other treatments, it focuses on addressing vitamin D deficiency, which has been linked to cognitive decline and dementia risk.¹ ³ ⁴ ⁵ ⁶

What data supports the effectiveness of the drug Vitamin D3 in preventing dementia?

Research suggests that higher levels of vitamin D in the blood are linked to a lower risk of dementia and Alzheimer's disease. A study found that increasing vitamin D levels by 10 units could reduce the risk of dementia by 5% and Alzheimer's by 7%.¹ ² ³ ⁷ ⁸

Who Is on the Research Team?

John Olichney, MD

Principal Investigator

UC Davis Alzheimer's Disease Center

Are You a Good Fit for This Trial?

This trial is for older adults aged 65-90 with low vitamin D levels and varying degrees of cognitive function, from no impairment to mild Alzheimer's disease. Participants must have a certain score on a cognitive test (MOCA), be fluent in English or Spanish, and willing to take high-dose or standard vitamin D. Exclusions include severe vision/hearing issues, MRI incompatibility, chronic psychiatric illness, substance abuse history, pregnancy plans during the trial, and certain medical conditions.

Inclusion Criteria

My diagnosis ranges from no cognitive impairment to mild Alzheimer's disease.

For No Cognitive Impairment (NC) subgroup: No significant cognitive impairment on baseline neuropsychological tests, minimum MOCA score of 23 or above for education >12 y, or MOCA >20 for education <12 y

I am between 65 and 90 years old.

See 5 more

Exclusion Criteria

Unable to undergo MRI scanning

I have had kidney stones multiple times.

My vitamin D levels are low and I have a history of osteoporosis.

See 15 more

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

Up to 6 weeks

1 visit (in-person)

Baseline

Participants are enrolled and randomized to high-dose or standard-dose Vitamin D treatment

1 day

1 visit (in-person)

Treatment

Participants receive either high-dose or standard-dose Vitamin D supplementation

3.5 years

Visits at months 6, 12, 18, 24, 30, 36, and 42

Follow-up

Participants are monitored for safety and effectiveness after treatment

4 weeks

What Are the Treatments Tested in This Trial?

Interventions

Vitamin D3

Trial Overview The study tests if high-dose Vitamin D3 (4,000 IU daily) can correct insufficiency better than the standard dose (~800 IU daily) in elderly people at risk for dementia. It also examines whether higher doses affect cognitive decline over 3½ years using brain scans and genetic markers related to Vitamin D reception.

How Is the Trial Designed?

2Treatment groups

Experimental Treatment

Active Control

Group I: High Dose Vitamin D3Experimental Treatment1 Intervention

Receives 4000 IU daily Vitamin D3 tablets.

Group II: Standard Dose Vitamin D3Active Control1 Intervention

Receives 600 IU Vitamin D3 tablets.

Vitamin D3 is already approved in European Union, United States, Canada, Japan, China, Switzerland for the following indications: