Amyloid Lowering for Alzheimer's in Down's With Donanemab Investigation (NCT06911944) | Clinical Trial Compass
Not Yet RecruitingPhase 4
Amyloid Lowering for Alzheimer's in Down's With Donanemab Investigation
60 participantsStarted 2026-08-01
Plain-language summary
The goal of this clinical trial is to learn if donanemab can reduce levels of amyloid in the brain, and if donanemab is safe and well-tolerated in participants with Down syndrome.
The main questions it aims to answer are: Does donanemab reduce amyloid in the brain? Is donanemab safe and well-tolerated in people with Down syndrome? Researchers will compare donanemab to a placebo (a look-alike substance that contains no drug) to see if donanemab works to reduce levels of amyloid in the brain.
Participants in the study will be 35-50 years old and will be in the study for 12 months. Participants will then stay in the study for an additional 12 months in an long-term extension where all participants will receive donanemab. Participants who had a reduction in amyloid (measured by amyloid brain scan) by the end of the first 12 months will receive placebo for the long-term extension, while participants who did not have an amyloid reduction will receive study donanemab for the long-term extension. Everyone (participants and study staff) will remain blinded to treatment for the duration of the study.
Participants will:
* Have intravenous (IV) infusions of donanemab (or placebo) every 4 weeks
* Visit the clinic once every other month for checkups and tests. These tests will include brain scans (magnetic resonance imaging \[MRI\] and positron emission tomography \[PET\] ), blood draws and memory tests.
* Have a study partner who who can provide information about the participant and can join participant for some of the study visits.
Who can participate
Age range
35 Years – 50 Years
Sex
ALL
See this in plain English?
AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.
Inclusion criteria
. Documentation of the participant's informed consent to study procedures
. Ages 35-50 years (inclusive).
. Plasma Phosphorylated tau (pTau) 217 levels at screening consistent with amyloid PET eligibility.
. Diagnosis of Down syndrome (including trisomy 21, mosaic trisomy 21, Robertsonian translocation trisomy 21, or partial trisomy 21) as confirmed by medical record review or Karyotype genetic testing.
. Intelligence quotient (IQ) equal to or greater than 40 based on Kaufman Brief Intelligence Test, Second Edition.
. Participants must be in good general health as evidenced by medical history with no diagnosis of dementia.
Questions worth asking your doctor
Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.
1This trial is testing donanemab specifically in people with Down syndrome to lower amyloid in the brain — is my loved one's current stage of Alzheimer's or amyloid buildup the kind this drug is designed to target?
2Since the trial hasn't started recruiting yet, what does the timeline realistically look like, and would waiting for enrollment affect my loved one's current treatment or disease progression in the meantime?
3Donanemab has been associated with brain swelling and bleeding (called ARIA) in other Alzheimer's trials — given that people with Down syndrome may have different health profiles, what additional safety risks should we be aware of before considering this study?
4This is a Phase 4 trial, which means the drug has already gone through earlier testing — does that mean there's more safety data available compared to earlier-phase trials, and how does that change the risk-benefit conversation for someone with Down syndrome?
5Are there standard-of-care treatments or other clinical trials already available that we should compare against this study, especially given that we'd need to wait for it to open before my loved one could even be screened?
Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.
Questions for the trial coordinator
The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.
1What does taking part actually involve week to week — how many visits, where, and how long does each one take?
2What costs are covered by the study, and what might I have to pay for myself, including travel, parking, or time off work?
3What happens during screening, and what happens if the study team confirms I don't meet the criteria after those tests?
4Who pays for the scans, blood work, and other tests the trial requires — the study, my insurance, or me?
5How will being in the trial affect my regular care, and will my own doctor stay informed and involved?
6Can I leave the trial at any point if I change my mind, and what would happen to my care if I do?
A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.
. Elevated brain amyloid (\>18 centiloids) at screening.
. Stable dose of permitted medications as described protocol for 4 weeks prior to screening.
Exclusion criteria
. Females who are lactating or pregnant (as confirmed by a urine pregnancy test) during screening, or plan to become pregnant during the study.
. Females of childbearing potential or males with a female partner of childbearing potential who did not use a highly effective method of contraception within 28 days of screening alongside with a suitable barrier method (e.g., male condom) and/or are not willing to use both methods for the duration of their participation in the study and for 3 months after the last dose of study drug.
. Weight less than 40kg at screening.
. Lack of good venous access such that intravenous (IV) drug delivery or multiple blood draws would be precluded.
. Suspected or known allergic reactions, adverse reactions, or hypersensitivity to humanized monoclonal antibodies or any components of the study treatments (donanemab or placebo).
. Previous treatment with donanemab unless there is firm evidence that the participant received placebo only.
. Prior or current treatment with a prohibited medication as described in protocol.
. Enrollment in another investigational study, or intake of investigational drug, within 30 days prior to screening or five half-lives of the investigational drug, whichever is longer.