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Clinical Trials

Frequently Asked Questions

What is a clinical trial?
A clinical trial is a study of a medical treatment in human subjects. The medical treatment can be a drug; a surgical device such as an artificial hip; a medical device such as an insulin pump; or a surgical technique. The purpose of a clinical trial is to answer questions about safety and effectiveness. We use them to determine whether we are using the best treatments or to help the Food and Drug Administration (FDA) determine whether or not to approve a treatment for general use.
What are the different phases of a clinical trial?
  • Pilot Study A pilot study is a first look to test an idea. It usually involves one or a very small number of participants. Because it is so early in the development of the idea, there is very little specific information for the participants and very careful observations are required. These studies are designed to be completed in a short period of time.
  • Phase I Study Focus is on safety in humans, and it usually lasts from 6 to 12 months. The study involves initial administration of an investigational drug to a small number of participants to determine the safe dose range for the drug. Observations are made regarding how the drug is absorbed, metabolized, eliminated and to test for obvious side-effects. Some evidence of the drug' potential effectiveness may also be obtained. Phase I studies may be performed on healthy volunteers, or on patients with the specific disease the drug is intended to treat.
  • Phase II Study The clinical administration of a new drug to a limited number of patients for a short period of time to determine the drug' safety and benefit in treating or preventing disease.
  • Phase III Study The administration of a new drug to a large number of participants in different clinical settings to determine its benefits and safety. In Phase III studies, a drug is used as it would be when ready to be marketed. When these studies are completed and the sponsor can demonstrate that the drug is safe and effective under specific conditions, the sponsor applies to the Food and Drug Administration (FDA) for clearance to market the drug to the public.
  • Phase IV Study Clinical studies for determination of after-effects and secondary results. The study is conducted after the FDA has cleared the drug for marketing. It is initiated by the producer of the drug to gain more information about its safety and benefits.
Why do people participate in clinical studies?
Common reasons include the lack of a generally accepted therapy or the partial effectiveness of available therapies. Participating in a clinical study might offer the patient a new alternative to "standard" treatment before it will be available to the general public. Many people volunteer for participation in clinical studies because they are survivors of a disease, like cancer, and want to do all they can to prevent cancer in their children. Others want to contribute to research efforts that may help others in the future.
Who pays for clinical research?
Mayo Clinic sponsors certain clinical studies initiated by the physicians as part of its ongoing commitment to clinical research. Additional funding may come from the federal government (via the National Institute of Health), voluntary health agencies such as the National Multiple Sclerosis Society, private industry (via pharmaceutical and biotech companies), or from philanthropic private donations to the Mayo that are earmarked for Research. According to Mayo Clinic policies, physicians cannot be paid for conducting clinical studies. Instead, they are allowed the time required to give proper attention to each participant of a clinical study.
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 by contributing to medical research
Who can participate in a clinical trial?
All clinical trials have guidelines about who can participate. Using inclusion/exclusion criteria is an important principle of medical research that helps to produce reliable results. The factors that allow someone to participate in a clinical trial are called "inclusion criteria" and those that disallow someone from participating are called "exclusion criteria". These criteria are based on such factors as age, gender, the type and stage of a disease, previous treatment history, and other medical conditions. Before joining a clinical trial, a participant must qualify for the study. Some research studies seek participants with illnesses or conditions to be studied in the clinical trial, while others need healthy participants. It is important to note that inclusion and exclusion criteria are not used to reject people personally. Instead, the criteria are used to identify appropriate participants and keep them safe. The criteria help ensure that researchers will be able to answer the questions they plan to study.
What happens during a clinical trial?
The clinical trial process depends on the kind of trial being conducted. The clinical trial team includes doctors and nurses as well as social workers and other health care professionals. They check the health of the participant at the beginning of the trial, give specific instructions for participating in the trial, monitor the participant carefully during the trial, and stay in touch after the trial is completed. Some clinical trials involve more tests and doctor visits than the participant would normally have for an illness or condition. For all types of trials, the participant works with a research team. Clinical trial participation is most successful when the protocol is carefully followed and there is frequent contact with the research staff.
What is informed consent?
Informed consent is the process of learning the key facts about a clinical trial before deciding whether or not to participate. It is also a continuing process throughout the study to provide information for participants. To help someone decide whether or not to participate, the doctors and nurses involved in the trial explain the details of the study. If the participant's native language is not English, translation assistance can be provided. Then the research team provides an informed consent document that includes details about the study, such as its purpose, duration, required procedures, and key contacts. Risks and potential benefits are explained in the informed consent document. The participant then decides whether or not to sign the document. Informed consent is not a contract, and the participant may withdraw from the trial at any time.
What are the benefits and risks of participating in a clinical trial?
Benefits:

Clinical trials that are well-designed and well-executed are the best approach for eligible participants to:
  • Play an active role in their own health care.
  • Gain access to new research treatments before they are widely available.
  • Obtain expert medical care at leading health care facilities during the trial.
  • Help others by contributing to medical research.

Risks:

There are risks to clinical trials.

  • There may be unpleasant, serious or even life-threatening side effects to treatment.
  • The treatment may not be effective for the participant.
  • The protocol may require more of their time and attention than would a non-protocol treatment, including trips to the study site, more treatments, hospital stays or complex dosage requirements.
What are side effects and adverse reactions?
Side effects are any undesired actions or effects of drug or treatment. Negative or adverse effects may include headache, nausea, hair loss, skin irritation, or other physical problems. Experimental treatments must be evaluated for both immediate and long-term side effects.
How is the safety of the participant protected?
The ethical and legal codes that govern medical practice also apply to clinical trials. In addition, most clinical research is federally regulated with built in safeguards to protect the participants. The trial follows a carefully controlled protocol, a study plan which details what researchers will do in the study. As a clinical trial progresses, researchers report the results of the trial at scientific meetings, to medical journals, and to various government agencies. Individual participants' names will remain secret and will not be mentioned in these reports.

Every clinical trial at Mayo Clinic must be approved and monitored by Mayo’s Institutional Review Board (IRB) to make sure the risks are as low as possible and are worth any potential benefits. An IRB is an independent committee of physicians, statisticians, community advocates, and others that ensures that a clinical trial is ethical and the rights of study participants are protected. All institutions that conduct or support biomedical research involving people must, by federal regulation, have an IRB that initially approves and periodically reviews the research.

What should people consider before participating in a trial?
People should know as much as possible about the clinical trial and feel comfortable asking the members of the health care team questions about it, the care expected while in a trial, and the cost of the trial. The following questions might be helpful for the participant to discuss with the health care team. Some of the answers to these questions are found in the informed consent document.
  • What is the purpose of the study?
  • Who is going to be in the study?
  • Why do researchers believe the new treatment being tested may be effective? Has it been tested before?
  • What kinds 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?
  • Will hospitalization be required?
  • Who will pay for the treatment?
  • Will I be reimbursed for other expenses?
  • What type of long-term follow up care is part of this 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?
Does a participant continue to work with a primary health care provider while in a trial?
Yes. Most clinical trials provide short-term treatments related to a designated illness or condition, but do not provide extended or complete primary health care. In addition, by having the health care provider work with the research team, the participant can ensure that other medications or treatments will not conflict with the protocol.
Can a participant leave a clinical trial after it has begun?
Yes. A participant can leave a clinical trial, at any time. When withdrawing from the trial, the participant should let the research team know about it, and the reasons for leaving the study.