About Clinical Research Trials

Introduction

Some men with prostate cancer may be eligible to participate in a clinical research trial. This section provides basic information regarding clinical research trials so that you can gain an understanding of what a clinical research trial is. You can discuss this information with your physician. In this section you will learn about:

  1. What is a clinical research trial?
  2. What are the possible risks and benefits of participating in a clinical research trial?
  3. What are the different phases of a clinical research trial and what do they mean?
  4. What is a placebo?
  5. What is informed consent?
  6. What else should I know about clinical research trials?

1. What is a Clinical Research Trial?
A clinical research trial is a carefully controlled study conducted in humans to determine whether an investigational therapy (investigational drug) is safe and effective in treating a particular disease or condition. This includes looking at the benefits and the risks of the investigational therapy.

2. What are the possible risks and benefits of participating in a clinical research trial?
The possible risks of participating in a clinical research trial include:

  • You may experience side effects to the investigational drug
  • You may receive a drug that may be less effective than current therapy
  • You may receive a drug which may be ineffective for you
  • You may receive a placebo (does not apply to all clinical research trials)

The possible benefits of participating in a clinical research trial include:

  • You may obtain expert medical care by leading physicians in the field of cancer research
  • You may gain access to investigational drugs not available to other patients
  • You will have your health closely monitored, and you will be evaluated for any side effects you may experience
  • You may be one of the first to benefit from an investigational drug if the treatment is found to be effective
  • You will be contributing to the advancement of knowledge in the treatment of cancer

3. What are the different phases of a clinical research trial and what do they mean?
Clinical research trials are conducted in humans only after laboratory and animal studies have outlined the potential safety and efficacy of the investigational drug.

Investigational drugs are tested in a series of clinical research trials that progress in "phases." There are four phases of clinical research trials. Phases one through three are conducted before a drug is approved by the Food and Drug Administration (FDA). The fourth phase occurs after the drug has received FDA approval.

Phase I Trials

Phase I trials are the first to be conducted in humans. They are used to determine the safe dosing of the investigational drug being tested.

Phase II Trials

Phase II trials begin to test the effectiveness of the investigational drug in a specific disease (like prostate cancer) while continuing to monitor the drug’s safety.

Phase III Trials

If the investigational drug has been shown to have a beneficial effect in phase II, phase III trials are initiated. Phase III trials help to gain a better understanding of the drug's efficacy, side effects, and potential risks and benefits. These studies compare the drug either to the existing therapies or a placebo. It is usually after phase III trials that the FDA determines if the drug should be approved.

Phase IV Trials

Phase IV trials are usually conducted after a drug has been approved by the FDA. Phase IV trials provide additional information about the drug's safety and/or efficacy.

4. What is a placebo?
A placebo is a substance or formulation (e.g., tablet, capsule, pill, liquid or powder) that has no treatment value. It is an inactive substance. In some clinical research trials, an investigational drug is compared with placebo to determine if the drug is more effective than giving no therapy (the placebo).

5. What is informed consent?
Informed consent is the process of learning about the clinical research trial through discussions with your physicians and deciding whether or not you want to participate. If you decide to participate in the trial, you will be required to sign a consent form. Remember, you are free to ask the research staff any questions before, during, and after the trial. And most importantly, you have the right to stop participation in the trial at any time.

6. What else should I know about clinical research trials?
Here are some additional terms that you may need to be aware of when considering clinical research trials:

Randomization: Randomization means that each patient has the same chance of being assigned to the investigational drug group or the control group. Not all cancer clinical research trials include randomization.

Control Group: A control group is a group of individuals or patients in the study who receive a standard treatment or placebo instead of the investigational drug. Control groups are used in clinical research trials that are designed to compare an investigational drug to an existing standard of treatment or to placebo. The results from the investigational drug group are compared to the results from the control group. Not all cancer clinical research trials have control groups.

Single-blind study: In a single-blind study, the patient does not know whether they are receiving the investigational drug or the control. Blinding only applies to randomized trials.

Double-blind study: In a double-blind study, the patient and the researcher/physician do not know if the patient is receiving the investigational drug or the control. Blinding only applies to randomized trials.

Open-label study: In an open-label study, both the patient and the researcher/physician know which therapy the patient is receiving (investigational drug or the control). Open-label studies are not blind and they may or may not be randomized.

Links
For further information regarding clinical research trials, please refer to the following web sites: