AuthorisedHuman Pharmacology (Phase I)- First administration to humansInterventional

A Phase 1, Randomized, Placebo-controlled Study with a Double-blind Period with Open-label Extension Period to Evaluate the Safety, Tolerability, Pharmacokinetics and Pharmacodynamics of Intrathecally Administered ALN-5288 in Adult Patients with Alzheimer’s Disease

This research study is about a new medicine called ALN-5288, which is being investigated for people living with Alzheimer's disease. It's a 'Phase 1' study, which means it’s one of the very first times this medicine is being given to human volunteers. The main goals are to check if the medicine is safe and if people can tolerate it well. Researchers will also learn how the medicine moves through the body and what effects it might have. This study starts with a 'double-blind' period, where neither the patient nor the doctor knows if they are receiving the actual medicine or a dummy treatment (placebo). After that, there's an 'open-label' period where everyone knows what treatment is being given. The medicine is given directly into the fluid around the spinal cord.

At a glance

Status

Authorised

Phase

Human Pharmacology (Phase I)- First administration to humans

Sponsor

Alnylam Pharmaceuticals Inc.

Enrolment target

Start

10 Feb 2026

Alzheimer’s Disease

What is this study about?

This study is a very early step in trying to find new treatments for Alzheimer's disease. Researchers are testing a new medicine called ALN-5288 for the first time in people. The main purpose of this initial stage is not to cure Alzheimer's, but to carefully check if the new medicine is safe for people to take and to understand how their bodies react to it. This kind of research is really important because it helps scientists decide if a medicine is promising enough to be studied further.

The medicine, ALN-5288, is given directly into the fluid that surrounds your brain and spinal cord, which is called 'intrathecal administration'. This method might help the medicine get to where it needs to go more effectively. The study is designed to be very careful, starting with a period where some participants receive the actual medicine and others get a dummy treatment (placebo), without anyone knowing who gets what. This helps researchers get clear information without bias. Later, everyone involved will know which treatment is being given.

By taking part in studies like this, volunteers play a crucial role in advancing our knowledge of Alzheimer's disease and helping develop potential future treatments. Even though this won't be a cure, the information gathered is vital for future research that could one day make a big difference for people with this condition.

Key takeaways

This is an early-stage study for a new Alzheimer's medicine.
The main goals are to check safety and how the body uses the medicine.
The medicine is given by an injection into the fluid around the spinal cord.
Participation involves regular clinic visits and health checks.
You might receive the new medicine or a dummy treatment (placebo) initially.
Your involvement helps advance research into Alzheimer's disease.

Who may be eligible?

To be considered for this study, you would need to be an adult, at least 18 years old. There is no upper age limit, meaning older adults are also welcome to be considered. The study is open to both men and women.

Because this is an early-stage study, researchers are looking for people who have a clear diagnosis of Alzheimer's disease. Specific medical criteria will need to be met, such as how advanced your Alzheimer's is, and other health conditions you might have. These details are checked very carefully by the study doctors.

It’s important to understand that there will be other medical checks and requirements that aren't listed here. The study team will review your full medical history and perform various tests to make sure that taking part would be safe for you and that you meet all the necessary requirements for the study.

Quick self-check

Are you an adult aged 18 or over?
Do you have a diagnosis of Alzheimer's disease?
Are you able to attend regular clinic appointments?
Are you willing to receive injections into your spinal fluid if needed?
Are you comfortable with the possibility of receiving a placebo treatment?

This is a guide only — the research team will confirm whether you can take part.

What does participation involve?

If you decide to take part, you would first go through a screening period, where doctors would check if the study is right for you. If you qualify, you would then enter the main study. Part of the study involves a 'double-blind' period, meaning you might receive the new medicine or a dummy treatment, and neither you nor the doctors will know which one. This is followed by an 'open-label' period where everyone knows the treatment being given.

The medicine, ALN-5288, is given by an injection into the fluid around your spinal cord (called an intrathecal injection). This procedure is done by trained medical professionals. You would need to attend several clinic visits for these injections, as well as for various tests and assessments. These might include blood tests, physical examinations, memory tests, and perhaps scans.

There will be regular follow-up appointments to monitor your health and any effects of the medicine. The total length of your participation would be discussed in detail by the study team, and it can vary depending on the specific study design, but generally, early-phase studies can last several months.

Potential risks and benefits

Taking part in any medical study has potential benefits and potential risks. A possible benefit is that you would receive close medical attention and monitoring throughout the study. You might also contribute valuable information that could help in the development of future treatments for Alzheimer's disease, benefiting others even if the medicine doesn't directly help you. However, as this is a new medicine, there is no guarantee it will help your condition, and there's a chance it could have side effects, some of which might be unknown. The injection into your spinal fluid also carries its own small risks, such as headache or infection, which the medical team will explain fully. You are always free to withdraw from the study at any time, for any reason, without it affecting your usual medical care.

Locations (2)

—
Spain
—
Netherlands

Common questions

What does 'Phase 1' mean?

Phase 1 means this is one of the very first times this new medicine is being tested in people. The main aim is to check if it's safe and how the body handles it, not to treat the disease just yet.

What is 'intrathecal administration'?

This means the medicine is given by an injection directly into the fluid that surrounds your brain and spinal cord, usually in the lower back.

What is a 'placebo'?

A placebo is a 'dummy' treatment that looks just like the real medicine but contains no active ingredients. It helps researchers compare the effects of the new medicine accurately.

Will I know if I'm getting the real medicine or the placebo?

During the first part of the study (the 'double-blind' period), neither you nor the doctors will know. This changes in the later 'open-label' part, where everyone will know.

Can I stop being part of the study whenever I want?

Yes, absolutely. You are free to leave the study at any time, for any reason, and it will not affect your medical care.