Clinical trials help researchers find better ways to detect, treat, and prevent diseases. These trials, which rely on volunteers, have taught us how Alzheimer’s affects the brain. Thanks to clinical research, we’re learning more about the disease and how to fight it. Clinical trials also show whether new treatments are safe and effective for people living with Alzheimer’s disease.

Before a new drug becomes available in the United States to treat Alzheimer’s, it must be approved by the U.S. Food and Drug Administration (FDA). To be eligible for approval by the FDA, the new treatment must perform well in all phases of its clinical trials, confirming it to be safe and effective.

If you or a loved one has Alzheimer’s, you might be curious to know if a clinical trial would be right for you. Here’s some important information to guide you when discussing Alzheimer’s clinical trials with your doctor.

Clinical Trials Are Leading To New Alzheimer’s Treatment

Alzheimer’s disease develops when proteins build up in the brain, forming clumps called amyloid plaques and twisted fibers called neurofibrillary tangles. These changes cause brain cells to die and, over time, make the brain shrink. Among the U.S. population 65 years old or older, around 6.9 million adults have Alzheimer’s.

Thanks to clinical trials, new types of Alzheimer’s treatments have been developed in the past few years. These include:

• Aducanumab (Aduhelm) was approved in June 2021, the first new Alzheimer’s medication in 18 years. It targeted amyloid plaques that develop in the brain. However, it was discontinued in late 2024 because it was not widely used — not because it wasn’t safe or effective.
• Lecanemab (Leqembi) was granted FDA approval in January 2023. Lecanemab also targets amyloid plaques in the brain.
• Donanemab (Kisunla) is another treatment that targets amyloid plaques in the brain. It received FDA approval in July 2024.

Many other potential Alzheimer’s treatments are currently being studied in clinical trials, including vaccines and treatments for Alzheimer’s psychosis.

The National Institute on Aging has information about the hundreds of active clinical trials on Alzheimer’s disease and other dementias it supports.

Some of these new treatments may help treat Alzheimer’s in its early stages before it progresses. Complications of advanced stages of Alzheimer’s — infection, dehydration, and malnutrition — are very serious, sometimes leading to death. Treating Alzheimer’s disease early may help prevent serious problems and slow down cognitive decline, which is a gradual loss of memory and clear thinking.

Clinical Trials Potentially Provide Access to New Treatments

Researchers use clinical trials to test how well new treatments work. Sometimes, people enrolled in research studies receive new, experimental treatments that are not yet available to the public. These new treatments may prove to be more effective than currently available therapies. However, there’s also a chance that the experimental treatments may not work or may cause some serious adverse effects, which are harmful or unwanted side effects.

Not everyone in a clinical trial will get the new treatment. Some people receive a placebo — a substance with no active ingredients. In placebo-controlled trials, participants are randomly assigned to receive either the experimental treatment or a placebo.

If placebos are used as an alternative treatment, they’re often made to look the same as the experimental drug, so that participants don’t know which intervention they’re getting. This is called a “single-blind” trial. In many cases, the researchers and study staff also don’t know which treatments participants are getting, this is called a “double-blinded” trial. Double-blinded trials help keep the results fair by making sure no one involved influences the outcome.

Some clinical trials may later offer the real treatment to people who got the placebo. This gives them a chance to see if the treatment helps. But this doesn’t always happen — it depends on how the trial is set up and what the results show.

Clinical Trial Participants Are Told if They Might Receive a Placebo

If a clinical trial includes a placebo, participants will be informed. Knowing you might get a placebo instead of the experimental treatment could affect your decision to join the trial. If there’s already a treatment for the condition — called the standard of care — you may get that instead of a placebo.

Randomization is another way researchers avoid bias. If an experimental treatment is much more effective than the placebo, the trial may be stopped early so participants can receive the better treatment.

If the experimental treatment works well, people who got the placebo or standard treatment might be able to receive it after the trial is over.

Clinical Trials Are Designed To Protect Participants’ Safety

The federal government regulates clinical trials in the United States. Before being studied in a clinical trial, a new treatment has to undergo extensive testing to make sure it’s safe and effective. If a new treatment shows promise in laboratory and animal tests, it may then be studied in humans.

Research studies are voluntary. You can choose not to enroll, and if you do join, you can leave at any time.

Institutional Review Boards Oversee Clinical Trials

Before they can begin, new trials must be approved by an institutional review board (IRB). An IRB typically includes doctors and ethics specialists — people who make sure the trial is fair, safe, and follows ethical guidelines. It’s the IRB’s job to ensure that a study will address medically important questions responsibly. If a study becomes unsafe for its participants, the IRB will order it to be stopped immediately.

Informed Consent

If you’re interested in enrolling in a clinical trial, you’ll first have to go through the informed consent process. Research coordinators will explain how the trial will work — the study design and procedures — and discuss its potential risks.

People with Alzheimer’s may not be able to make their own decisions, depending on whether they’re in early or later stages of the disease. If a doctor determines that cognitive impairment affects a person’s ability to make decisions, they may not be able to give informed consent on their own. In these cases, a healthcare proxy or legal representative may provide consent for the person with Alzheimer’s to participate. When a proxy or representative is involved, study coordinators will give them the clinical trial information and they’ll be asked to sign the consent form.

Phases of Clinical Trials

Clinical trials are performed in four phases so that researchers can safely evaluate a treatment’s effectiveness and risks. The phases of clinical trials are:

• Phase 1 — Typically small, these trials are used to determine the highest dose of a new drug that’s safe. Participants are followed primarily for side effects and not to evaluate the effect of the drug on their condition.
• Phase 2 — Larger than phase 1 studies, these trials evaluate how effective a drug is on a specific condition as well as its side effects.
• Phase 3 — The largest studies, these trials assess how effective and safe a new treatment is. If phase 3 trials are successful, a treatment can be approved by the FDA.
• Phase 4 — Studies done after approval to check long-term safety and how well the treatment works.

People Have Different Reasons for Participating in a Clinical Trial

Being a part of an Alzheimer’s clinical trial is a personal decision. For some, the opportunity of accessing a new therapy that may improve their quality of life drives them to enroll. For others, financial considerations may be involved, as clinical trial sponsors may cover the costs of an experimental treatment. Part of the cost may also be covered by health insurance.

Clinical trials also allow people an opportunity to be involved in research that may significantly change how Alzheimer’s is treated. The additional care offered by a clinical study — monitoring and follow-ups — may motivate others to participate.

Each Clinical Trial Has Eligibility Requirements

Clinical trials have unique guidelines that qualify people for enrollment. Eligibility for a clinical trial depends on specific criteria, such as age, medical history, and disease stage.

How To Find a Clinical Trial

If you’re interested in enrolling in an Alzheimer’s clinical trial, there are several ways to search for studies.

The Alzheimer’s Association TrialMatch can help match you, or someone you care for, with an Alzheimer’s study. In addition, you can search for clinical trials related to Alzheimer’s through the following organizations:

• National Institutes of Health
• Alzheimers.gov
• Alzheimer’s Disease International

You can also browse the Alzheimer’s Disease Research Centers funded by the National Institute on Aging.

Ask Your Doctor

If you’re considering an Alzheimer’s clinical trial, your doctor is a great resource. They can explain how trials work, what to expect, and whether one might be a good fit for you. You can also ask about other ways to support Alzheimer’s research, such as joining research registries or observational studies. Even if you don’t participate, learning about new treatments can help you stay informed about advances in Alzheimer’s care.

Find Your Team

On myALZteam, the social network for people with Alzheimer’s disease and their loved ones, more than 86,000 members come together to ask questions, give advice, and share their stories with others who understand life with the condition.

Have you participated in a clinical trial? Do you have advice for people who are thinking about joining a clinical study? Share your experience in the comments below, or start a conversation by posting on your Activities page.