Clinical trials are important to test the safety and effectiveness of new treatments for Lou Gehrig's disease (ALS). Learn more about the different stages of ALS clinical trials below.

If you or a loved one has ALS, you know the heartbreaking frustration that there are not yet treatments that can stop or significantly slow the disease. You may not know that there are hundreds of scientists and doctors working hard to discover those treatments. That discovery depends, in large part, on the willing spirit of people with ALS who volunteer to be a part of a clinical trial.

The search for new therapies usually begins in the laboratory, where ideas for new treatments are tested in cell cultures or animal models. These steps are critical for showing whether a potential treatment has any merit at all. A treatment that fails in the lab is put aside. But one that succeeds there must still be tested in the most important arena of all, the clinical trial.

A clinical trial is the best way researchers have developed to find effective treatments, and, equally importantly, to weed out useless or harmful ones. Clinical trials are costly, and may last months. When the treatment being tested proves to not be effective, it can be sorely disappointing. But clinical trials have proven to be the most reliable way, and ultimately the fastest way, to discover treatments that really work.

Understanding Clinical Trial Phases

There are several types of clinical trials, each of which is important to test both the safety and effectiveness of the new treatment, such as a drug for ALS.

Phase I Trial

The drug is given to a small number of people, either healthy volunteers or people with ALS, to see if it is safe in humans. The numbers are kept small in order to expose as few people as possible to an untried treatment. In fact, by the time a Phase I study begins, researchers have a great deal of confidence that the drug is likely to be quite safe, based on their results from other experiments; nonetheless, the Phase I trial is critical to determine safety. A Phase I trial may also begin to test whether the drug is effective in treating ALS, but this is not its main purpose, and any positive results can only be considered tentative.

Phase II Trial

A drug that is safe can be initially tested for effectiveness in a Phase II trial. This trial typically enrolls between 30 and 50 people with ALS. Most Phase II trials test the drug against a placebo—an identical pill (or injection, or other form of delivery) that does not contain the drug (this is called a placebo-controlled trial). Neither the researcher nor the ALS patient knows which is which. In this way, their hope of benefit from the real treatment will not affect the results. If the drug continues to appear safe, and shows some signs of effectiveness, it will be tested in the next phase, Phase III.

Phase III Trial

A phase III trial is considered the definitive test of whether a drug is effective. It is always a placebo-controlled trial, and enrolls many more patients than a phase II trial. It is usually conducted by multiple researchers at multiple different sites around the country or even around the world. A treatment that succeeds in a Phase III trial is considered to be truly effective. Once a successful trial is over, the company that manufactures the drug can apply to the United States Food and Drug Administration (FDA) for permission to market the drug for treatment of ALS.

The urgent need for new treatment for ALS can only be met when researchers and people with ALS work together. ALS researchers know that most ALS patients would like to help them develop new treatments. But they also understand the concerns that may make patients and families hesitant to enroll in a trial. Researchers are striving to shorten clinical trials, and make them more convenient for patients and families to take part in.

To learn more about clinical trials, read on about the vital importance of placebo-controlled trials, and about how you can get involved in a clinical trial in your area.

Getting Involved in a Clinical Trial

People with ALS who enroll in a clinical trial are contributing to improved healthcare for everyone with the disease. Even when the results of a trial are negative, we learn that much more about the disease, and how to look for more promising new treatments.

Volunteering for an ALS trial is a big decision. Staff at Mass General can help answer your questions.

Common Questions About Clinical Trials

How do I find out about clinical trials?
To see what ALS trials are available at Mass General, check our list here. Various trial options are available through the Healey Center for ALS, including placebo-controlled clinical trials (which test the effects of experimental treatments) and observational studies (which collect health data to contribute to knowledge about ALS).

You can also search a comprehensive list of clinical trials for all conditions is at This website is a central database of virtually all clinical trials in the United States, and even contains information from other countries. The site is easy to search, and will provide you detailed information about trials in ALS, to help you find trials that may be right for you.

If you have questions about clinical trials or observational studies, ask your doctor and ALS study team or contact our clinical trials enrollment and coordination service for assistance.

How do I know which trial I would qualify for, and which is right for me?
Not every ALS trial is right for every person with ALS. Each trial listed will have information on eligibility that indicates who might be appropriate for the trial.

The eligibility information includes inclusion criteria—characteristics a participant must have—such as a specific age range, disease duration, or subtype of ALS.

Eligibility information also includes exclusion criteria—characteristics that make someone ineligible for enrollment—such as other illnesses or other drug treatments.

Other information you may want to consider are the location of trial centers, the duration of the trial, and any requirements or restrictions that affect you. These are listed in the description of the trial.

Will a trial prevent me from activities or other treatments I value?
The inclusion and exclusion criteria differ for each trial. Some trials exclude people who are taking medications for other illnesses, such as hypertension or diabetes. Some trials exclude people with ALS who are taking other investigational treatments for ALS. In both cases, it would be inappropriate or dangerous to be enrolled in the trial.

In most cases, the person with ALS will continue to receive exactly the same treatments and care as usual, and the investigational treatment will just be added on. Researchers are committed to maintaining the highest level of treatment of all people enrolled in a clinical trial.

How much of a commitment is participation in a clinical trial?
Trials vary greatly in the amount of effort they require from participants. Some trials, especially with drugs known to be safe, won’t require you to visit the trial site much more often than your normal clinical care requires. Sometimes, trial activities can be performed over the phone. Other trials require more frequent monitoring to maximize safety.

The experimental drug may be something you can take by mouth, or might be administered by injection or infusion into your bloodstream. These differences will change both the risks of a trial and the amount of time and effort required of you. When you discuss a trial with people performing it, they should be very clear about these issues. If you are still uncertain after a trial is described to you, keep asking questions.

Does it cost me anything to enter a trial?
There should not be any cost to the participant to enroll in a clinical trial in ALS, either for the treatment itself, or for the medical examinations that are part of the trial. If you need to travel to reach the treatment center, you may have to pay for that, although many trials include funds to help participants defray these costs. The trial contact personnel can tell you more about that for each specific trial.

If I enter a trial, can I drop out of it before the end?
Yes. You may always drop out at any time, for any reason. However, trials produce better information if people stay involved until the end of the trial, so you should not begin a trial unless you plan to complete it.

If you do need to drop out, be sure to inform the doctor who is treating you before you do so. There are some drugs that are not safe to stop all at once, but should be tapered off gradually. It is also valuable to the research team to know who has dropped out, when, and why.

Will I learn the results of the trial, and whether or not I was on placebo?
At the end of any trial, the results are analyzed and then made public. Trial participants are informed of all results, as well as whether they were taking the active drug or the placebo.

What is informed consent, and why is it important?
When you give “informed consent” to be involved in a trial, it means you are agreeing to participate after learning about the potential risks and benefits of your involvement, along with your rights and responsibilities. Members of the research team will explain these to you, and ask you to sign a document indicating you understand what they have said, and are giving your informed consent to be involved. Before you sign, be sure to ask as many questions as you need to fully understand the trial and your involvement in it.

How do I enroll in a clinical trial?
Once you’ve identified a trial you may be interested in, read the detailed information about it on the site. If you have questions, talk with your doctor, or with the study personnel. If you think the study is right for you, contact the study personnel and let them know. You’ll find contact information on for each study that is currently recruiting new patients.