Clinical Trials - Phases

Clinical Trials studies are part of a thorough research process

  • Clinical trials start with a scientist who gets an idea about:
    • A new treatment for cancer
    • A different way to give a treatment for cancer
    • Or, a way to reduce the side effects of a treatment
  • This process begins in the laboratory (pre-clinical trials studies) and once the drug or technique looks like it may be both safe and effective, it is tried out on people who volunteer to take part in the study
  • There are different risks and benefits related to each stage or phase of a clinical trial.
  • That is one reason why two people may be enrolled in a breast cancer clinical trial, but they may have totally different experiences.
  • This shows the complete process for creating a new, more effective drug for cancer treatment. It goes from laboratory science in a test tube to animals or computers and then to people (sometimes called, "from bench to bedside")
  • This is "Stage #1 of the Clinical Trials Process" for a new cancer treatment

Basic Research

  • Done in a laboratory
    • Usually uses a microscope or other technical equipment
    • Looks at cells and smaller parts (genes)
  • The end result is a new drug that may be helpful in treating cancer

Preclinical Studies

  • Experiments using the potential drug on mice, rats, pigs, dogs and other small animals
  • Newer methods use computers rather than animals
  • The end result is a new drug that may be helpful in treating cancer in humans

Clinical Trials in People

There are 4 phases involved in clinical trials process in people

Phase I:  Safety

  • To learn the best and safest way to give a new treatment and begin to learn about possible side effects
    • The patients have advanced cancer and:
  • Have gone through standard treatments
  • But the treatments are not working
  • Or, their disease changed
    • Because there is no better treatment to offer the patient, these patients are willing to try something experimental
    • Done with small numbers of patients (usually less than a total of 30)
  • Groups of three people at a time try a new treatment
  • They try one dose of the new drug and see what happens
  • If the drug seems to be working, another group of three try a stronger dose of the drug
  • If that dose still seems to be working, another group of three try an even stronger dose of the drug
  • This continues until the dose has too many bad side effects
    • Patients are not expected to personally benefit, but the information learned is likely to help other cancer patients
  • The patient may or may not benefit, but "personal benefits" cannot be promised to the patient.
  • It is important that the patient realizes the benefits of taking part in the study will be passed on to other cancer patients

Phase II Efficacy

  • To learn if the new drug works better for different types of cancer
  • To learn about possible side effects
  • Done with larger numbers of patients (usually less than a 100)
  • The patients have:
    • Never been treated
    • Shown little to no response to previous drug treatment
    • Or, relapsed after standard treatment

Phase III. New versus Standard Treatment

  • To learn how a possible new treatment compares to the current standard treatment for a specific type and stage (early; advanced) of cancer
  • Done with large numbers of patients (100's to 1,000s)
  • The patients:
    • Have never been treated
    • Or, a previous treatment didn't work for them
  • In cancer clinical trials, no "sugar pill" (placebo) is used
    • If a treatment exists for your type of cancer and you are in a clinical trial:
      • You will always receive at least the standard treatment given to others with this type of cancer
      • You may also receive a treatment that may be even better than the standard treatment
  • These studies may see if a new drug or combination of drugs is better than what is currently given as standard treatment
    • Maybe drugs "A" "B" and "C" are compared to drugs "A" "B" "C" and "D" ("D" is the new drug)
  • Many clinics across the US and Canada will offer these types of trials
  • These are done to get Food and Drug Administration (FDA) approval of a new drug

Phase IV. Post-marketing;  Post Food and Drug Administration (FDA) Approval

  • To learn how a treatment may also work in different types of cancer
    • After Taxol was found to work for breast cancer, then in a Phase IV study it was tried in males with prostate cancer
  • These are very rare studies
  • These studies are becoming more common
  • These are done to get FDA approval of a new use of an approved drug or a new method of giving a new drug
  • Done with large numbers of patients (100's to 1,000s)
  • Similar to a Phase III, but with patients who have a different type of cancer

Summary of CT Phases

  • Phase I trials are only available in a few locations and is for people who have not responded well to existing treatments.
  • Phase II trials are limited to a small number in only a few locations
  • Phase III trials are available in clinics throughout North America
  • Phase IV are rarely available, but are becoming more common