Your introduction
to clinical trials
A clinical trial is a research study where volunteers help test investigational products. These can include drugs, vaccines, devices, or other medical approaches. Investigational products have not yet been approved for the condition being studied.
Clinical trials are carefully designed to find out:
- If the investigational product works
- If it's safe
- If it causes any side effects
Clinical trials are an important way to help improve care for people with different health conditions.
Your introduction
to clinical trials
A clinical trial is a research study where volunteers help test investigational products. These can include drugs, vaccines, devices, or other medical approaches. Investigational products have not yet been approved for the condition being studied.
Clinical trials are carefully designed to find out:
- If the investigational product works
- If it's safe
- If it causes any side effects
Clinical trials are an important way to help improve care for people with different health conditions.
Types of clinical trials
There are different types of clinical trials:
Interventional trials
Doctors give you an investigational product to see if it works and is safe.
Observational trials
Doctors track your health over time without giving you any investigational products. This shows how a condition affects people naturally.
Post-marketing trials
After an investigational product is approved, researchers study it in more people to learn about its long-term safety and how well it works.
All these trials help improve medicine.
The phases of clinical trials
Clinical research for investigational products follows a clear path with 4 phases. Each phase builds on the one before, testing both safety and how well the product works.
The purpose of this phase is to test if the investigational product is safe in a small group (20-80 people). Some trials may include healthy volunteers.
What is being studied?
- The safety of the investigational product.
- How the investigational product is processed and removed from the body.
- How the body reacts to different doses.
- Possible side effects.
What is needed to move onto the next phase?
The investigational product is generally safe and handled well by the body.
What should you consider before joining?
You may be one of the first people to try the investigational product. The risks are not well-known.
1 min video
Healthy
volunteers
volunteers
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The purpose of this phase is to test if the investigational product is safe in a small group (20-80 people). Some trials may include healthy volunteers.
What is being studied?
- The safety of the investigational product.
- How the investigational product is processed and removed from the body.
- How the body reacts to different doses.
- Possible side effects.
What is needed to move onto the next phase?
The investigational product is generally safe and handled well by the body.
What should you consider before joining?
You may be one of the first people to try the investigational product. The risks are not well-known.
1 min video
Healthy
volunteers
volunteers
Download transcript
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The purpose of this phase is to test if the investigational product works in people who have the condition (50-300 people). These trials continue to monitor safety.
What is being studied?
- The safety of the investigational product.
- Whether the investigational product works for the condition being studied.
- What the best dose of the investigational product is.
What is needed to move onto the next phase?
- The investigational product shows signs it may help.
- The dose is safe enough to use in larger groups.
What should you consider before joining?
- The investigational product is still early in development. The goal is to see if it works, but benefits are not guaranteed.
- In some trials, you may get a placebo. A placebo looks like the real investigational product but doesn't have any active medicine in it.
The purpose of this phase is to test if the investigational product works in people who have the condition (50-300 people). These trials continue to monitor safety.
What is being studied?
- The safety of the investigational product.
- Whether the investigational product works for the condition being studied.
- What the best dose of the investigational product is.
What is needed to move onto the next phase?
- The investigational product shows signs it may help.
- The dose is safe enough to use in larger groups.
What should you consider before joining?
- The investigational product is still early in development. The goal is to see if it works, but benefits are not guaranteed.
- In some trials, you may get a placebo. A placebo looks like the real investigational product but doesn't have any active medicine in it.
The purpose of this phase is to test the investigational product in a large group (300-3,000 people). These trials compare the new product to existing treatments.
What is being studied?
- Safety in bigger groups of people.
- Whether the investigational product works for the condition being studied.
- How the investigational product compares to existing treatment options.
What is needed to move onto the next phase?
- The investigational product works as well as (or better than) current treatments.
- The dose is still safe when used in many people.
- The investigational product is approved by authorities for public use.
What should you consider before joining?
- Depending on the trial, you may get either a placebo or the usual treatment that doctors give for the condition, also called the standard of care.
- These trials often last longer and need more clinic visits.
The purpose of this phase is to test the investigational product in a large group (300-3,000 people). These trials compare the new product to existing treatments.
What is being studied?
- Safety in bigger groups of people.
- Whether the investigational product works for the condition being studied.
- How the investigational product compares to existing treatment options.
What is needed to move onto the next phase?
- The investigational product works as well as (or better than) current treatments.
- The dose is still safe when used in many people.
- The investigational product is approved by authorities for public use.
What should you consider before joining?
- Depending on the trial, you may get either a placebo or the usual treatment that doctors give for the condition, also called the standard of care.
- These trials often last longer and need more clinic visits.
The purpose of this phase is to monitor how the investigational product works after it is approved and being used by many people (1,000 or more).
What is being studied?
Long-term risks and benefits of the treatment in everyday use in the real world.
What is needed to move onto the next phase?
There is no next phase. Information may lead to updates in how the approved treatment is used.
What should you consider before joining?
This phase is usually less involved. You may give updates through follow-up visits, phone calls, or surveys.
The purpose of this phase is to monitor how the investigational product works after it is approved and being used by many people (1,000 or more).
What is being studied?
Long-term risks and benefits of the treatment in everyday use in the real world.
What is needed to move onto the next phase?
There is no next phase. Information may lead to updates in how the approved treatment is used.
What should you consider before joining?
This phase is usually less involved. You may give updates through follow-up visits, phone calls, or surveys.
Drug trials usually follow a set path with Phases 1 through 4. Some trials may combine phases to study multiple aspects of an investigational product at once.
Trials for medical devices are often called “pre-market” or “post-market” trials. The path for testing new medical devices depends on the type of device as well as other factors.
4 min video
The 4 phases of
clinical research
clinical research
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What to know about joining a clinical trial
Participating in a clinical trial is a big decision. There are several reasons why people join.
Access an investigational product being studied for their condition.
Learn more about their disease or condition.
Contribute to science that may improve care for future patients.
Support representative research so results can better reflect the population the investigational product is meant to help.
No matter the reason, the decision to participate is always your choice. Talk to your doctor and ask questions. It's about what's right for you.
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