2014 11:40:10 AM

About Clinical Trials


Ever wonder what a clinical trial is and what is involved? Where it begins? How a substance goes from a molecule in a lab to the pharmacy shelf?

The research process starts with years of pre-trial testing and ends with several phases of clinical trials. During these, studies on human volunteers are used to find out whether promising approaches to disease prevention, diagnosis and treatment are both effective and safe for patients.

To develop a single drug, research scientists start with approximately 10,000 natural and synthetic substances. These substances are screened to determine whether they influence specific disease-related reactions. Those lacking desirable pharmacological effects are weeded out, leaving perhaps 100 candidates. These substances are tested in cell or organ cultures for harmful biochemical properties, and are patented even before their clinical benefit is fully established. Researchers then use in vivo (real-life) tests to determine whether, and in what amounts, the substance acts in a complex organism. Perhaps only 20 molecules will remain in the running at this point, and three (3) years will have passed. At this point, researchers pass the baton to drug developers, and the clinical trials begin. Now, the substances are tested for the first time on humans.

There are several different types of clinical trials:

  • Treatment trials test new treatments;

  • Prevention trials examine new approaches;

  • Quality of Life trials, also called supportive care trials, explore ways to improve comfort and quality of life for cancer patients; and

  • Screening trials determine the best way to detect cancer, especially in its early stages.

Most clinical research involves the testing of a new drug and occurs through an orderly series of steps called phases.

  • Phase I Trials are the first to enroll humans and are designed to determine how a new drug should be given (by mouth, injected into the blood, or injected into the muscle), how often it should be given, and at what dosage. A phase I trial usually involves only a small number of patients, sometimes as few as a dozen.

  • Phase II Trials continue to test the safety of the drug and begin to evaluate how well the new drug works; for cancer medications, these trials usually focus on a particular cancer site.

  • Phase III Trials compare a new drug, a new combination of drugs, or a new surgical procedure to the current standard. Usually, a participant is assigned at random to either the standard group or the new group (given the new protocol). Phase III trials enroll large numbers of people and may be conducted at many doctor's offices, clinics, and cancer centers across the nation. Once Phase III trials are complete, the pharmaceutical company analyzes the data to determine whether the experimental drug is both safe and effective.

  • Phase IV Trials are performed after the drug has been shown to work and the company has been granted a license to manufacture and sell it. This trial is looking at drugs that are available for doctors to prescribe, rather than new drugs that are still being developed. The main reason to conduct Phase IV trials is to find out more about the side effects and safety of the drug, its long term risks and benefits, and how well the drug works for purposes other than its original intended use. By the time the drug is on the market, it has taken 10 - 20 years of research and up to $1,000,000,000 dollars to develop.

For more information about participating in a clinical trial, please contact Eileen Mederos, our NCORP Interim Program Manager, at (504) 407-7395.