Clinical Trials


Enrolling in a clinical trial is not something that should be done lightly or without a good deal of thought. While there may be advantages to you, your family and to society, there are likely to be risks as well. People enroll in clinical trails for a variety of reasons. Some are seeking out new treatments for themselves or family members. Others have an interest in a particular disease. Many people find out about clinical trials from their physician. Others are identified through ads in local newspapers, television and radio announcements and posters. Regardless of why you may be considering enrolling in a clinical trail or how you found out about it, you will need some additional information before making a decision.

What Are Clinical Trials?

Clinical trials are studies done in humans that are designed to answer very specific questions. Examples of kinds of issues that clinical trials might examine include the use of a new treatment or a new diagnostic test, the impact of the environment on a disease, or how genetics determine clinical outcomes. When done correctly, clinical trials can add to our understanding of health, disease, diagnosis and treatments. The overwhelming majority of clinical trials are done responsibly. However, this was not always the case. As a result, a series of regulations have been established that define the ways in which studies should be done and provide for both government and institutional oversight.

Ethical Guideposts

All clinical trials done in the United States fall under a complex and sometimes bewildering set of state and federal regulations. The regulations are designed to protect the people who participate in clinical trials. Although they require a bit of interpretation, the regulations are actually well constructed and are based on a series of time-honored principles. The foundations for the regulations lie in two documents produced by the National Institutes of Health: the Nuremberg Code and the Belmont Report. Simply put, the regulations ensure:

  • Respect for persons — People have the right of self determination and should enroll in clinical trials of their own free will. Those with diminished capacity should have special protections.
  • Beneficence — Clinical trials should be designed to maximize possible benefit and minimize possible harm.
  • Justice — People participating should be fairly chosen without undue regard to race, ethnicity, religion, social status or gender.

To make sure that these principles are carried out, the federal government in 1974 mandated the formation of an oversight committee at every institution that conducts clinical trials. The committees, called institutional review boards (IRBs), were given the responsibility of ensuring the protection of people participating in clinical trials. The IRBs must have people from the community serving as full members in addition to experts from the medical profession and other professional staff. The activities of the IRBs are regulated by both the federal and in some cases state governments. In addition to meeting standards set by the government, IRBs can seek to be accredited by well-respected national organizations such as the Association for the Accreditation of Human Research Protection Programs and others.

Types of Clinical Trials

Most clinical trials fall into one of three general categories:

  1. An observational study — The study only involves the collection of information without any type of personal testing or sampling
  2. A non-interventional study — The study could include collecting blood or urine samples, a specific meal plan, an exercise program, or monitoring sleep patterns.
  3. An interventional study — These are the studies that might require taking a new drug or an old drug for a new indication, undergoing diagnostic testing, or having a surgical procedure.

From the standpoint of risks, interventional studies usually are at the top of the list, with non-interventional and observational studies ranking second and third, respectively.

Observational Clinical Trials:

Observational clinical trials involve the collection of information. There are no study procedures or laboratory tests. No new drugs or diagnostics are involved. Your involvement is usually limited to allowing the collection of:

  • Information about your care and your progress while in treatment
  • Specimens that are already routinely collected during care. The specimens can have additional tests run on the same samples. Another example is having tissue that was removed during necessary surgery examined for something more than the initial intent.
  • Your responses to a series of questions about treatment or living with a particular disease

The major risks of being part of an observational study are risks to privacy. Observational studies can involve the collection of a great deal of information about you and your family.

Non-Interventional Clinical Trials
Non-intervention trials are very similar to observational studies but there is some procedure that is done just for the study. The procedures are usually defined as having very low risks such as the collection of a small blood sample, urine sample and the like. Non-interventional studies also can involve other kinds of noninvasive diagnostics such as ultrasound or MRI. Like in observational studies, a good deal of information is sometimes collected, so privacy can be a concern. The actual study procedures should be of very low risk as well.

Interventional Clinical Trials

Interventional trials are studies that do involve some action performed solely for study purposes. The intervention can include:

  • A new drug or biological agent
  • A new vaccine
  • A new radiology test
  • A new surgical or other kind of procedure

Interventional studies usually include some form of risk. The risks may be directly related to the drug or test or procedure. There is also the risk of not receiving the standard drug, test or procedure if you are assigned to the experimental group and the experimental action turns out to be less effective.

Interventional trials involving new drugs are usually conducted in a stepwise fashion (called phases). Each phase has a different purpose and helps answer different questions:

  • In Phase I trials, researchers test a new drug or treatment in a small group of people, usually without disease, to test its safety, determine a safe dosage range, and identify side effects.
  • In Phase II trials, the study drug or treatment is given to a larger group of people with the disease to see if it is effective and to continue to evaluate it for safety.
  • In Phase III trials, the study drug or treatment is given to large groups of people with the disease to confirm its effectiveness, monitor side effects, compare it to commonly used treatments, and collect information that will allow the drug or treatment to be used safely. Phase III trials may also include the use of placebo or a standard drug or treatment for the disease.
  • In Phase IV trials, the risks and benefits of the treatment are evaluated after the approval from the U.S. Food and Drug Administration. These are called “post marketing studies,” and they are designed to obtain real-world information of the value of the treatment.

The decision to enroll in a clinical trial is one that should only be made after you have done a bit of homework. People who enroll in trials can play a more active role in their health care, gain a better understanding of diseases and treatments, gain access to new and perhaps more effective therapies, and help others. But there are usually some risks.

Here are some commonly asked questions adapted from the clinical trials website of the National Institutes of Health.

How can I find out about clinical trials?

There are a number of sources available. Perhaps one of the best is your personal physician. You also can find out about clinical trials by contacting a teaching hospital near you. You also can look at a number of national sources such as Center Watch.

Who can participate in a clinical trial?

Clinical trials are designed to answer very specific questions. Because the presence of other diseases or drugs may change the results of the study, most clinical trials have strict requirements for who can enroll. The requirements are described in the inclusions (who may enroll) and exclusions (who may not enroll) section of the protocol. Inclusion and exclusion criteria usually include the presence or absence of the disease or disorder, stage of the disease, age, previous treatments, and sometimes gender. Exclusion criteria should not be designed to exclude people on a personal basis (for example, because of race or ethnicity, unless the study is designed specifically to seek an answer to a question for people of one race). The inclusion and exclusion criteria should be based on sound scientific reasons that help to answer the question posed and ensure the safety of people in the study.

What should I consider before participating in a trial?

You should know as much as possible about the clinical trial before enrolling. A list of things to think about is noted below. You should feel comfortable asking the study staff and investigators these questions.

  • 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?
  • What will happen at the end of the study?
  • 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?

How should I prepare myself before meeting with the research coordinator or doctor?

  • Plan ahead and write down possible questions to ask.
  • Ask a friend or relative to come along for support and to hear the responses to the questions.
  • Bring a tape recorder to record the discussion to replay later.

Every clinical trial in the United States must be approved and monitored by an 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 who ensure 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 is informed consent?

Before you can participate in a clinical trial you will be asked to provide your informed consent. To do so, you must be told about the study, its risks and benefits, and exactly what will be done and how long you will participate. The researchers must be willing to answer your questions, and you should have as much time to think about enrolling as you need and the study design will allow. Once you have a good understanding of what is involved and what the potential risks and benefits are, you must be allowed to enroll voluntarily.

Informed consent is a process that requires good communication between you and the study staff. If English is not your native language, interpreters should be available. (Some studies use questionnaires that have not been shown to give reliable information in other languages. These studies may require people who enroll to speak English.) The process is documented using an informed-consent form. The form includes the details of the study, including its purpose, time requirements, procedures, risks, benefits and alternatives. You will be asked to sign the form, acknowledging that you have agreed to participate. You will be enrolled in the study when you sign the consent form. It is important to know that the consent form is NOT a contract. You can change your mind and decide against participating at any time

How will my safety be 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 that 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

Can I leave a clinical trial after it has begun?

You can change your mind and withdraw from the 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.

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