A clinical trial is a research study to answer specific questions about a new medical treatment, or new ways of using known treatments. Clinical trials are used to determine whether such new treatments are both safe and effective. In a clinical trial, participants receive a specific intervention according to the protocol. These interventions may be medical products, such as drugs or devices, procedures, or changes to the participants’ behavior (such as diet). Clinical trials may compare a new medical approach to a standard one that is already available, or to a placebo that contains no active ingredients or to no intervention.

What is clinical research?

Clinical research is research conducted with human subjects, or material of human origin, in which the researcher directly interacts with human subjects.

Why participate in a clinical trial?

Participants in clinical trials can play a more active role in their own health care, gain access to new research treatments before they are widely available, and help others to medical research.

What are clinical trial “phases”?

Phase I: The purpose of a phase I study is to assess the safety of a drug or device. Phase I studies usually includes a small number of healthy volunteers (20 to 100). The study is designed to determine the effects of the intervention on humans (including how it is absorbed, metabolized, and excreted). This phase also investigates the side effects that occur as dosage levels are increased.

Phase II: The purpose of a phase II study is to test the efficacy of a drug or device. Most phase II studies are randomized trials where one group of patients receives the experimental drug, while a second “control” group receives a standard treatment or placebo. Often these studies are “blinded” which means that neither the patients nor the researchers know who has the experimental drug or standard treatment or placebo. Blinded studies allows investigators to provide the pharmaceutical company and FDA with comparative information about the relative safety and effectiveness of the new drug.

Phase III: Phase III studies involve randomized and blind testing in several hundred thousand patients. This large-scale testing provides the pharmaceutical company and the FDA with a more thorough understanding of the effectiveness of the drug or device, the benefits and the range of possible adverse reactions.

Phase IV: Phase IV studies are often called Post Marketing Surveillance Trials. These studies are conducted after a drug or device has been approved for consumer sale. The objectives of a study at this phase is: (1) to compare a drug with other drugs already in the market; (2) to monitor a drug’s long-term effectiveness and impact on a patient’s quality of life; (3) to determine the cost-effectiveness of a drug therapy relative to other traditional and new therapies.

What are blind studies?

A blinded study is a clinical research trial in which participants, the subject or the investigator (or both), are unaware as to whether they are in the experimental or control arm of the study.

What is a control group?

A control group is a scientific study where the drug or factor being tested is not applied so that it may serve as a standard for comparison against another group where the drug or factor is applied. A control group is useful to make conclusions more accurate or precise.

What is a placebo?

A placebo is a medication with no active ingredients or a procedure without any medical benefits. A placebo is often used as a “control” in one group of people in order to study the effectiveness of an experimental drug or treatment in another group of people by comparing results.

What is a protocol?

A protocol is a study plan specific to each clinical trial. The plan is carefully designed to safeguard the health of the participants as well as answer specific research questions. A protocol describes what types of people may participate in the trial, the schedule of tests, procedures, medications, dosages, and the length of the study. Participants in a clinical trial are seen regularly with the research staff to monitor their health and determine the safety and effectiveness of their treatment.

Who can participate in a clinical trial?

Clinical trials have standards in the protocol outlining who can participate. These standards are called eligibility criteria. The factors that allow someone to participate in a clinical study are called inclusion criteria, and the factors that disqualify a participant is called exclusion criteria.  The criteria is based on things such as age, gender, the type and stage of a disease, previous treatment history, and other medical conditions.

Can a participant leave a clinical trial after it has begun?

Participants may withdraw from a trial at any time, even if the study is not over. The participant should let the research team know about it, and the reason for leaving the study.

How long do clinical trials last?

The length of a clinical trial varies, depending on what is being studied and the protocol. Participants are told how long the study will last before enrolling.

Who conducts clinical trials?

Every clinical trial is led by a principal investigator, who is often a medical doctor. Clinical trials also have a research team that may include doctors, nurses, social workers and other healthcare professionals. Clinical trials can be sponsored or funded by pharmaceutical companies, academic medical centers, voluntary groups, and other organizations.

What is an Institutional Review Board?

An Institutional Review Board (IRB) is made up of physicians, researchers and members of the community. The role of an IRB is to make sure that the study is ethical and the rights and welfare of the participants is protected. This includes making sure that risks are minimized and are reasonable in relation to any potential benefits, among other things. The IRB also reviews the informed consent form.

What should I consider before participating in a clinical trial?

People should know as much as possible about the clinical trial and feel comfortable asking the members of the research team about it and the care expected while in a trial. The following questions might be helpful for the participant to discuss with the research team:

  • What is the purpose of the study?
  • Why do researchers believe the new treatment being tested may be effective? Has it been tested before?
  • What kind of tests and treatments are involved?
  • How do the possible risks, side effects, and benefits in the study compare with my current treatment?
  • How might this trial affect my daily life?
  • How long will the trial last?
  • What type of long-term follow up care is part of the study?
  • How will I know that the treatment is working?
  • Will results of the trials be provided to me?
  • Who will be in charge of my care?

What happens during a clinical trial?

The clinical trial process depends on the kind of trial being conducted. The clinical trial team checks on the health of the patient at the beginning of the trial, gives specific instructions for participating in the trial, monitors the patient carefully during the trial, and stays in touch as appropriate after the trial is completed.

What is informed consent?

Informed consent is a process in which researches provide potential and enrolled participants with information about a clinical trial. The provided information will help people decide whether they want to enroll, or continue to participate, in the trial. The informed consent process is intended to protect participants and provide enough information for a person to understand the risks and potential benefits of participating in the trial. A person must sign an informed consent form before entering a trial to show that he or she was given information on risks, potential benefits, alternatives and understands them. An informed consent is not a contract.  Participants may withdraw from a trial at any time, even if the study is not over.