Prostate Cancer

Understanding clinical trials

Clinical trials are studies that evaluate whether new treatments are safe and effective in humans. In addition to validating a new drug or procedure’s safety and effectiveness, clinical trials help doctors determine the treatment’s side effects and best dosage. The results of clinical trials help the U.S. Food and Drug Administration (FDA) decide whether to approve the new treatment, which makes it available for public use. Without patient participation in clinical trials, the prostate cancer treatments we have today would not be available.

Benefits of participating in a clinical trial

Participating in a clinical trial offers many benefits, including early access to potentially effective new treatments and receiving the best standard of care and close monitoring by experts. Clinical trial participants also play an important role in the scientific process and can help other people with cancer. A clinical trial may help you, and your participation in one will definitely help doctors and future patients. Clinical trial participants are always volunteers and can leave the trial at any time for any reason.

Many people associate clinical trials with the use of a placebo. A placebo is an inactive pill or fake treatment used in some types of clinical trials. Some people may be nervous about participating in a clinical trial because they believe they could receive a placebo instead of real treatment. This is not true. Placebos are rarely used alone in cancer research, and they are never used instead of an effective treatment. People in cancer clinical trials will always receive the standard of care. Do not let the myth that you will receive a placebo instead of treatment dissuade you from participating in a clinical trial that could help you.

Safety in clinical trials

Clinical trials are safe for participants. All clinical trials must go through the same process to get the FDA’s approval. Strict scientific and ethical guidelines must be met and followed while each clinical trial is being developed and monitored. These studies are conducted under the direct supervision of physicians and expert research professionals, and every participating clinic, hospital, university or cancer center must follow the same set of rules, called a protocol.

The protocol outlines the eligibility criteria, specifies the tests that will be used and procedures that will be performed, describes the medications and their doses, and establishes the length of each study. Several safeguards are in place and regulated to guarantee the safety of all participants in a clinical trial.

Before researchers can study a treatment in humans, the treatment has to go through preclinical testing (laboratory or animal studies) to establish whether it is safe for humans and could work as intended. Preclinical testing can take several years to complete. At this point, the pharmaceutical research company must file an Investigational New Drug Application (IND) with the FDA. The IND must include results from the preclinical studies, protocols for all proposed clinical trials, and the drug’s ingredients, manufacturing and processing information. This gives the FDA a chance to review the study before participants are involved. A trial can enroll volunteers only after the FDA approves it.

Once a trial starts, it has many built-in safeguards that protect participants as the trial continues, such as an institutional review board (IRB). An IRB is a group of people responsible for protecting the rights and welfare of study participants and ensuring that the study complies with federal law.

How trials work

Each clinical trial establishes a set of characteristics its participants must have. This set is called eligibility criteria. Cancer type and treatment history are two common examples of eligibility criteria. The clinical trial staff will be able to determine whether you are eligible to participate in a specific trial.

Clinical trials are generally conducted in three distinct phases that build on each other. If you enroll in a clinical trial, it will most likely be one of these phases. Phase I trials are usually the first time the treatment is evaluated in humans. The goal of phase I trials is usually to determine the dose that works best without causing severe side effects. In a phase II trial, doctors learn more about the treatment’s safety and how well it works for a specific cancer. If the new treatment is likely to work and is as safe as the standard treatment, research moves to a phase III trial. A phase III trial enrolls more volunteers to compare the new treatment with the standard of care. With more volunteers, researchers have more data and can evaluate whether the new treatment really is better than the standard of care. The goal of a phase III trial is to find out whether the new treatment is better than the standard treatment and/or has fewer side effects than the standard treatment.

Finding a trial

Your location doesn't limit your participation because clinical trials now take place at local hospitals and cancer centers as well as at major medical centers. You may find one in your town, or you may have to travel. If you are interested in participating in a clinical trial, you have a few methods of finding one that’s right for you. Ask your medical team if they can recommend a clinical trial for you. Current clinical trials with open recruitment can be found at Trials labeled “open” are recruiting new volunteers, and trials labeled “closed” are not recruiting new volunteers. In addition, a number of government and private organizations provide listings of clinical trials and information about trials on their websites.

Clinical Trials Glossary

Arm: A group or subgroup of participants in a clinical trial that receives a specific intervention/treatment, or no intervention, according to the trial’s protocol.

Exclusion criteria: A type of eligibility criteria. These are reasons that a person is not allowed to participate in a clinical study.

Expanded access: A way for patients with serious diseases or conditions who cannot participate in a clinical trial to gain access to a medical product that has not been approved by the U.S. Food and Drug Administration (FDA). Also called compassionate use.

Inclusion criteria: A type of eligibility criteria. These are the reasons that a person is allowed to participate in a clinical study.

Informed consent: A process used by researchers to communicate to potential and enrolled participants the risks and potential benefits of participating.

Intervention/treatment: A process or action that is the focus of a clinical study.

Interventions and treatments include drugs, medical devices, procedures, vaccines and other products that are either investigational or already available. They can also include noninvasive approaches, such as education or modifying diet and exercise.

Investigator: A researcher involved in a clinical study. Related terms include site principal investigator, site sub-investigator, study chair, study director and study principal investigator.

NCT number: The unique identification code given to each clinical study upon registration at The format is NCT followed by an 8-digit number (for example, NCT00000419).

Phase: The stage of a clinical trial studying a drug or biological product, based on definitions developed by the U.S. Food and Drug Administration (FDA).

Primary outcome measure: In a clinical study’s protocol, the planned outcome measure that is most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.

Primary purpose: The main reason for the clinical trial. The types of primary purpose are treatment, prevention, diagnostic, supportive care, screening, health services research, basic science and other.

Principal investigator (PI): The person who is responsible for the scientific and technical direction of the entire clinical study.

Protocol: The written description of a clinical study. It includes the study’s objectives, design and methods. It may also include relevant scientific background and statistical information.

Sponsor: The organization or person who initiates the study and who has authority and control over the study.

Study completion date: The date on which the last participant in a clinical study was examined or received an intervention or treatment to collect final data for the primary outcome measure(s), secondary outcome measure(s) and adverse events (that is, the last participant’s last visit).

U.S. Food and Drug Administration (FDA): An agency within the U.S. Department of Health and Human Services. The FDA is responsible for protecting the public health by making sure that human and veterinary drugs, vaccines and other biological products and medical devices as well as the nation’s food supply, cosmetics, dietary supplements and products that give off radiation are safe, effective and secure.