A clinical study involves research using human volunteers (also called participants) that is intended to add to medical knowledge. There are two main types of clinical studies: clinical trials (also called interventional studies) and observational studies. 

Clinical Trials

On average it takes 12 years to get a new drug from the laboratory onto the pharmacy shelf. Once a company develops a drug, it undergoes around three and a half years of laboratory testing before testing the drug in humans. Only about one in 1,000 of the compounds that enter laboratory testing will ever make it to human testing.

In a clinical trial, participants receive specific interventions according to the research plan or protocol. When a new product or approach is being studied, it is not usually known whether it will be helpful, harmful or no different than available alternatives (including no intervention). The researchers try to determine the safety and efficacy of the intervention by measuring certain outcomes in the participants. 

Interventional clinical trials go through a series of phases:

• Phase I Trials - A new drug or treatment is given to a small group of people for the first time to find a safe dose, how to give the new treatment and identify side effects.
• Phase II Trials - A new drug or treatment is given to a larger group of people to see if the new treatment is effective and to further identify side effects.
• Phase III Trials - The drug or treatment is given to large group of people 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. Often the trial compares the
  new treatment with the currently prescribed standard of care. The drug or treatment is typically submitted to the U.S. Food and Drug Administration (FDA) after a Phase III trial to hopefully gain approval and make the treatment available to the general population. 
• Phase IV Trials - looks at the long term safety and effectiveness of a new treatment after the drug or treatment has been approved by the U.S. Food and Drug Administration (FDA). Studies are done to gather information on the drug's effect in various populations and any side effects associated with long-term use.

Observational Studies

In an observational study, researchers assess health outcomes in groups of participants according to a research plan or protocol. Participants may receive interventions (which can include medical products such as drugs or devices) or procedures as part of their routine medical care. However, participants are not assigned to specific interventions by the clinical trial). For example, researchers may observe a group of older adults to learn more about the effects of different lifestyles on cardiac health.

Each research informed consent document details the potential benefits of the specific study. In general, benefits of participating in a clinical trial may include:

• High-quality care
• Access to new treatments or new drugs
• Adding more staff to your care team
• Close monitoring of your health for any side effects
• A chance to help others and improve treatment
• Some portion of treatment may be paid by the clinical trial (detailed in each research informed consent document)

Every clinical trial has a research team. The trial is led by a principal investigator, who is often a medical doctor. Clinical trials also have a research team that may include additional doctors, clinical research coordinators, medical assistants, nurses, social workers and other health care professionals.

Clinical trials can be sponsored, or funded, by:

• Pharmaceutical companies 
• Academic medical centers 
• Voluntary groups and other organizations 
• Federal agencies such as:
  •     The National Institutes of Health 
  •     The U.S. Department of Defense 
  •     The U.S. Department of Veterans Affairs
   
• Doctors, other health care providers, and other individuals can also sponsor clinical research. 

The clinical trial sponsor is disclosed to all participants at the time of research informed consent.

The length of a clinical trial varies, depending on what is being studied. Participants are told how long the study is expected to last before deciding to participate.

Anyone interested in participating in a clinical trial should know as much as possible about the study and feel comfortable asking the research team questions about the study, the related procedures and any expenses. The following questions may be helpful during such a discussion. Answers to some of these questions are provided in the research informed consent document. Many of the questions are specific to clinical trials, but some also apply to observational studies. 

• What is being studied?
• Why do researchers believe the intervention being tested might be effective? Why might it not be effective? Has it been tested before?
• What are the possible interventions that I might receive during the trial? 
• How will it be determined which interventions I receive (for example, by chance)? 
• Who will know which intervention I receive during the trial? Will I know? Will members of the research team know? 
• How do the possible risks, side effects, and benefits of this trial compare with those of my current treatment?
• What will I have to do?
• What tests and procedures are involved?
• How often will I have to visit the hospital or clinic? 
• Will hospitalization be required?
• How long will the study last?
• Who will pay for my participation?
• Will I be reimbursed for other expenses?
• What type of long-term follow-up care is part of this trial? 
• If I benefit from the intervention, will I be allowed to continue receiving it after the trial ends?
• Will results of the study be provided to me?
• Who will oversee my medical care while I am participating in the trial?
• What are my options if I am injured during the study?

You are always welcome to contact the UW Medicine | Valley Medical Center Research Department directly at Research@ValleyMed.org or 425.690.3503.

ClinicalTrials.gov  | A service of the US National Institutes of Health

Cancer.gov  | National Cancer Institute

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