Your guide to clinical trials

1. What a clinical trial is

A clinical trial is a research study that tests a medicine, vaccine or treatment in people, following a written plan called a protocol. The protocol sets out who can join, what happens at each visit, and what the researchers are measuring.

Every medicine in your pharmacy went through trials before it was approved. The people who took part made it possible to know whether it worked and what its side effects were.

2. How a new medicine moves through the phases

Trials run in phases, and each one answers a different question. A medicine only moves to the next phase if the results so far justify it.

Phase I

Is it safe, and what dose should be used? Usually a small group, often closely monitored at the study site.

Phase II

Does it seem to work for the condition, and what side effects show up? A larger group who have the condition.

Phase III

How does it compare with the current standard treatment? Many people, often at sites across the country, before a medicine can be submitted for approval.

Phase IV

What happens once it is in everyday use? Studies that continue after approval to watch for rarer or longer-term effects.

3. Who can take part

Each study lists the people it is looking for. These lists are called eligibility criteria: inclusion criteria describe who can join, and exclusion criteria describe who cannot. They usually cover age, diagnosis, stage of illness, earlier treatment and other health conditions.

The criteria are there to protect participants and to make the results meaningful. Not matching one study says nothing about whether you would match the next.

4. Informed consent

Before anything happens, the study team walks you through a consent document: why the study is being done, what each visit involves, the known risks and possible benefits, and the alternatives open to you. Take it home, read it with family, and ask about anything that is unclear.

Signing it is not a contract. You can leave a study at any time, for any reason, and leaving does not affect the regular care you receive.

5. What happens during a study

Most studies start with a screening visit to confirm you meet the criteria. If you do, you are enrolled and the visits follow the protocol's timetable. A visit might include a check-up, blood tests, scans, questionnaires, or receiving the study medicine.

Some studies compare a new treatment against the current standard or against a placebo, an inactive look-alike. Many assign groups at random, and some keep the assignment hidden until the end so it cannot sway the results. The consent document tells you whether the study you are joining works this way.

6. How your safety is protected

An independent ethics board, called an Institutional Review Board, has to approve a study before it starts and keeps reviewing it while it runs. Trials of medicines in the United States also run under FDA rules.

The study team watches for side effects throughout, and you can tell them about any change in how you feel at any visit or by phone in between. If something serious happens, call 911 first. Our side-effect reporting page explains who to tell after that.

7. Time, travel and costs

What a study covers varies from one protocol to the next: the study medicine, visit tests, travel or parking, and payment for your time are all decided study by study. Ask the study team to put the details in writing before you agree.

Think about the timetable too. Some studies need a visit every few weeks for a year or more, and knowing that up front makes it easier to decide.

8. Questions worth asking the study team

• What is this study trying to find out?
• What will I have to do, and how often will I need to come in?
• Could I receive a placebo instead of the study medicine?
• What side effects have been seen so far?
• What will the study pay for, and what might I pay for?
• Who do I call if I feel unwell between visits?
• Will I hear about the results when the study ends?
• What happens to my care if I decide to stop?

Bring the list to the first conversation, and bring someone with you if that helps.

9. Hearing about Westbridge studies

Studies open at different times and in different places. If you would like to know when one starts enrolling in an area you care about, sign up for study texts and we will let you know. Signing up does not commit you to anything.