Clinical Trial Basics

Four Types of Trials with Cancer Research

Clinical Trials are in-depth medical research studies conducted to understand whether promising approaches to cancer prevention, diagnosis and treatment are safe and effective.

Cancer research, in general, includes four types of trials:

  • Treatment: research to test new approaches to treatment including new drugs, drug combinations, radiation and surgery
  • Prevention: research to investigate methods to prevent the disease from occurring in people who have previously not had cancer; or prevent the cancer from recurring in patients who previously have been diagnosed with the disease
  • Screening: research to find the optimum approach in detecting cancer before symptoms occur; includes imaging , laboratory and genetic testing
  • Quality of Life: research to investigate means of improving cancer patients' and survivors' quality of life; areas explored include the management of fatigue, nausea, pain, weight loss and depression associated with cancer treatments

Clinical Trial Phases

Clinical trials progress through a series of stages meant to ensure safety of patient and effectiveness of treatment:

  • Phase I: a drug or treatment is initially evaluated with a limited group (approximately 20-30) to determine its safety, optimal dose or treatment levels and identify side effects
  • Phase II: the experiemental study's drug or treatment is tested for safety and effectiveness and usually involves a larger number of participants (approximately 100-300) compared to Phase I
  • Phase III: the experimental study's drug or treatment is given (administered) to confirm findings of Phase II and to compare it to existing treatments. A greater amount of information is collected in order to determine the safety of the drug or treatment (typically involves 1,000-3,000 participants)
  • Phase IV: after the drug or treatment gains FDA approval, the study enters the marketing stage. This study observes the drug or treatment over a lengthy time period and involves a significantly larger number of participants (thousands). The purpose is to evaluate side effects, risks and benefits of a drug; and is typically conducted by the drug maker

Patient Benefits

  • Health care professionals play an active role in the patient’s health care
  • Patients have access to new treatments before being widely introduced
  • Patients receive top-level care at leading medical institutions
  • Patients play a valuable role in medical research with the potential to help other patients facing similar health challenges

Patient Risks

  • There is the potential for unpleasant side effects, including headache, nausea, hair loss or skin irritation
  • The treatment may not be effective or produce the desired result
  • Participation in a trial may involve a greater time commitment than pursuing non-trial treatment

More Trial Information

  • Participatory guidelines exist, and these are commonly known as “inclusion/exclusion criteria.”
  • All U.S. clinical trials are approved and tracked by an institutional review board to ensure risks are as minimal as possible and are worth the benefits.
  • Participants should be well-informed and understand as much as possible about the clinical trial and should feel comfortable asking questions. A few questions:
    • Who is in the study?
    • How do the potential side effects and benefits compare with my current treatment?
    • How might this trial affect my daily life?
    • Will hospitalization be required?
    • Who will be in charge of my care?