Clinical Trial Information

Clinical trial volunteers make new medicines possible. Lilly provides information to help you make an informed choice about participating in research studies. Discuss these topics with your healthcare provider.

About Clinical Trials

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What is a clinical trial?

A clinical trial is a research study that tests a medicine or therapy in people. Clinical trials can also be called clinical studies or clinical research. Clinical research helps us answer questions about the medicine being studied, like does the medicine work and is it safe.


The path to developing a new medicine is a long journey that can have stops and starts along the way. Different trials can follow different processes and can vary in length. However, for all trials, the research team will make sure that the medicine is properly tested.

10 Things You Need To Know About Clinical Trials

Have you ever thought about the contents of your medicine cabinet? The medicines inside may have different purposes, but they have one big thing in common; before reaching you, they went through years of research studies to ensure that they were safe for you to take. These research studies are called clinical trials.

Clinical trials provide important information about how safe and effective a medicine is. They generate detailed data that can often lead to creating even more new treatments. Every medicine goes through many phases of research, each with a different goal. Below is a short description of these phases;

  • Phase 1 trials: Researchers test a medicine or therapy in a small group of people for the first time to assess its safety and identify side effects.
  • Phase 2 and 3 trials: The medicine or therapy is given to a larger group of people to see if it works and to further check its safety.
  • Phase 4 trials: This involves use of the medicine in real-world experience over a long period of time. This provides more information on the benefits and risks of the medicine.

Ultimately, clinical trials can make a difference not just for today’s patients, but also for future patients.

Choosing to join a clinical trial is a personal and individual decision. According to the Center for Information and Study on Clinical Research Participation (CISCRP), common reasons for study volunteers to join a clinical trial include:

  • to advance science and treatments
  • to help others with the same condition or disease as them
  • to potentially obtain better treatment

Visit this CISCRP infographic to see why people are willing to take part, or not take part, in clinical trials: Deciding to Participate

One of the responsibilities of the healthcare team who run clinical trials is to care for participants . The people in this team may go by unfamiliar titles like Principal Investigator or Study Coordinator. But they are also doctors, nurses, and trained researchers. This means that they are trained to look after your safety and health. They may do this by talking with your personal healthcare team about your needs and treatment, or by talking to you about whether you want to continue in the trial.

Everyone conducting a clinical trial has strict regulatory and ethical duties. Teams of people, called an Ethics Review Board (ERB) or Institutional Review Board (IRB), operate independently from the day-to-day conduct of research. An ERB or IRB review every clinical trial before people can take part. This is to ensure that the correct steps are taken to protect participants' welfare and rights. An ERB or IRB protect participants by;

  • making sure that clinical trial risks are as low as possible for participants
  • ensuring the potential benefits of the clinical trial outweigh the risks
  • making sure that a clinical trial meets overall safety requirements for participants

Each clinical trial has different risks and benefits. And as each clinical trial volunteer is different, they will experience these risks and benefits in different ways. For example, one person may experience a side effect from the study medicine but another person might not.


Clinical trials are experiments, so the exact risks and benefits can be difficult to predict. Researchers only move forward with clinical trials when they are optimistic about the potential benefits and believe any risks for participants are acceptable. In addition, an Ethics Review Board (ERB) or Institutional Review Board (IRB) must review the study plan before researchers can ask participants to join. Researchers discuss the potential risks and benefits of a clinical trial with participants before they might agree to take part. This talk takes place during the informed consent process. This process helps participants understand what is involved in the study so that they can make an informed decision on whether to join.

The set of criteria to enter a clinical trial is chosen very carefully. For each trial, this set of criteria is needed to prove whether a medicine works or not in a specific patient population. These requirements are applied equally to potential participants before they join the study. Trial criteria are based on things like age, gender, the type and stage of a disease, previous treatment history, and other medical conditions.

Participants can withdraw from a clinical trial at any time, for any reason. No matter the stage of the trial, participants have the right to change their mind. If a study volunteer decides to leave the study, the Principal Investigator will remove them from the trial in a safe manner.

For most clinical trials, the study medicine is provided and visits are conducted at no cost to the participant. However, this is not the case for all trials.

Some clinical trials pay or reimburse participants. These payments, if any, tend to vary based upon the phase of the trial. For example, payment for a Phase 1 trial is often greater, as in this phase, the medicine being studied is less understood. On the other hand, payment for a Phase 4 trial is often only reimbursement for time and travel.

Participants learn about any costs or payments before deciding to join a clinical trial during the informed consent process .

Clinical trials can be conducted in many places including hospitals, universities, doctors' offices, and community clinics. Some activities for clinical trials may even take place in the partcipant's home.

In 2019, a survey by the Center for Information and Study on Clinical Research Participation (CISCRP) found that 96% of clinical trial participants would consider joining another clinical trial in the future. Also, 78% of respondents thought their experience in a clinical trial met or exceeded their expectations.

Who is involved in clinical trials?

Diversity

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Lilly's Commitment to Diversity in Clinical Trials

Representing different groups of people in clinical trials is extremely important. People respond differently to medicines depending on their age, sex, race, ethnicity and many other factors. By including diverse groups of people in our trials, Lilly can help to treat as many patients as possible.

Image with people from diverse backgrounds and of different ages

Paving the Way to Better Diversity in Clinical Trials

People of color are often underrepresented in society, including in clinical trials. Lilly wants to make sure that people of color have equal access to our clinical trials. Click below to find out more.

Considering Participation

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Why do people participate?

Every day, all over the world, countless people are involved in clinical trials, looking to find new and improved medicines. These medicines may offer potential treatment options for generations to come. Clinical trials provide important information that can help improve medical research and knowledge, but at the core of clinical research is the study participants who make this possible.


People choose to take part in clinical trials for a variety of reasons. They may want to monitor and better understand their own condition or help advance medical research that could benefit others. Whatever the motivation, choosing to participate in a clinical trial is a personal and individual decision.

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How to choose a trial?

Every clinical trial is different. Anyone interested in taking part in a trial should know as much as possible about the study and feel comfortable asking the research team any questions. Before meeting with the research coordinator or study doctor, plan ahead and write down some questions to ask. You may also wish to discuss this decision with your family, friends, or doctor.


Feel free to bring a friend or relative with you for support and to hear the responses to your questions. The following questions might be helpful during such a discussion. You can download or print these questions and take them with you.

What To Expect

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What happens before the trial?

Before joining a clinical trial, participants are given information about the study and have the chance to ask questions. This process is called informed consent. The purpose of the informed consent process is to make sure participants understand important details about the clinical trial so they can make an informed choice about taking part. Informed consent begins before a volunteer agrees to participate in a trial and continues throughout the study.

The informed consent document describes the study details. It includes the study’s purpose, length, procedures, risks and benefits, and other information that all participants should know. After discussing the study details, volunteers will sign the informed consent document. There may be more than one document for a study. The informed consent document is not a contract. Participants can withdraw from a study at any time, even if the study is not over.

How am I protected during the trial?

The research teams that conduct clinical trials must follow the same rules and regulations that other healthcare providers follow in addition to regulations by the federal government and requirements for the study. Protections are built into clinical trial processes to safeguard the wellbeing of participants.

What happens after my trial?

By taking part, you would add to the long history of volunteers around the world. Study volunteers can help researchers to answer important health questions and to discover new treatments that can make lives better.

After your participation has ended, you and your doctor should work together to determine the next best steps for your care. Sometimes studies are designed to provide access to the study medicine for longer periods after the study is over. However, this is the exception, not the rule, so please discuss this with your study doctor.

What happens after the trial results are analyzed depends on the phase of the trial. After a Phase 1 or 2 trial, the results will tell the researchers whether to move on to the next phase, or to stop testing the medicine because it was unsafe or ineffective. When a Phase 3 trial is complete, the researchers will examine the data and decide whether the results have medical importance.

Once a new medicine or treatment has been proven safe and effective during all three phases of trials, it may be approved for use. Researchers need to submit the research results to country-specific authorities (like the FDA in the US) in order to make the medicine available to patients. However, not all study drugs or treatments will be approved.

Obtaining the results of your trial will depend upon the study sponsor and the research site. Bear in mind that trial results can take some time to be available. Though you may have completed your participation in a clinical trial, that trial may still be ongoing for the other volunteers. And while some trials are completed in a week, others take several years.


If you participate in a Lilly clinical trial, you can find the study results on www.clinicaltrials.gov, either 30 days after the approval of the medicine (Phase 1) or within one year after a trial has completed (Phases 2-4). In addition, Lilly creates summaries of Phase 2 and 3 clinical trial results written in patient-friendly language using simple, everyday terms. These lay summaries are available for the study doctors to provide to study participants.

This site is intended for US residents.