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Benefits and risks of clinical trials

Clinical trials follow very strict scientific and ethical standards that protect the participants' health, safety and privacy. Each clinical trial involving a new therapy or a new way of delivering an existing treatment must be approved by Health Canada, the hospital or clinic where the study takes place and the study’s Research Ethics Board (REB). The REB is a committee of health professionals and individuals from the community that protect the participants of a clinical trial. These groups continue to watch over the trial until it is completed.

Choosing to participate in a clinical trial is an important personal decision. If people are considering taking part in a clinical trial, it is important for them to talk to their doctor about the possible benefits and risks.

Possible benefits

When an experimental treatment is being studied in comparison to a standard treatment, it is possible that the participant might not receive the new treatment being tested. However, the participant will receive the best standard cancer treatment available.

If the new drug being studied in a clinical trial works effectively to treat or prevent cancer, the participants in the study will be the first to benefit.

In learning about clinical research and joining a clinical trial, a person takes an active role in a decision that affects their life. This can be personally empowering.

The person may benefit from the extra follow-up care provided to participants.

The person has a chance to help others and to improve the treatment of cancer.

The person has a chance to further the knowledge of early detection, screening and diagnosis, supportive care and prevention of cancer, which could lead to improved outcomes.

Cancer screening trials may encourage participants to continue checkups on a regular basis, which can lead to overall improved health.

Possible risks

New drugs or treatments under study are not always better than, or as good as, the standard ones.

There may be unexpected side effects that may be worse than those caused by standard drugs or treatments. A person is watched carefully during the study in case they have a bad reaction to the new drug or treatment.

Although a new drug or treatment may have benefits, it may not work for every participant (just as a standard treatment may not work for everyone).

Participants that get standard treatment may not benefit as much as those receiving the new one (if it is found to be more effective at treating cancer).

Being in a clinical trial may take extra time or be inconvenient. A person may be required to have more tests or take extra medicines.


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