A Guide to Understanding Phase I and Phase II Clinical Trials of Medications

In recent years, there have been many new prescription medications that have become available. In addition, there have also been a lot of medications that used to be available only by prescription that can now be sold over the counter. However, in order to evaluate the risks, benefits, and safety of each new medication, extensive research is required, and four phases of clinical research are necessary. If you have ever seen an ad in the newspaper or on television about the need for volunteers to participate in clinical trials and thought that doing so might be a good idea, the following information about the first two types of clinical research will be very helpful.

Phase I Trials: Starting at the Beginning

Phase I trials are important because they are the very first time that a medication will be evaluated on human subjects, although the medication may have been tested previously on animals. It is not unusual for this first trial to take several months to complete, and there will usually be at least 20 and no more than 100 patients in this first testing experience. All of the participants in this first phase will be given the medication being tested. Factual feedback from each person is crucial. You may find clinical trials occurring in academic hospitals and private testing facilities.

In general, the participants are usually psychologically and physically healthy. Testing will involve evaluating how well the medication is processed by the clinical research participants. You should expect frequent monitoring to determine how a new medicine is used, broken down, stored, and released from your body. There is also likely to be a special emphasis on side effects and their severity, particularly as the dosages of the medication increase.

Phase II Trials: Testing More People

If the medicine or device in question seems successful based on the data from the first clinical trials, the medication will go on to a second phase. One primary difference between the two phases is that there will be a larger group of participants in the second phase. Another change is that Phase II testing may take up to two years to complete. A third deviation is that, as mentioned previously, everyone in a Phase I trials gets the medicine being tested while only about half of the individuals in the Phase II testing will.

Participants who do not get the actual medication being tested will receive a placebo, and those patients may still be asked to chart and report all side effects. Since the participants do not know what they are or are not being given, the information provided by the control group getting the placebo will contribute to the accuracy of the testing.

In conclusion, clinical trials exist to evaluate the safety, efficacy, and benefits of new medicines and medical devices. Clinical research is essential for treating, preventing and curing a wide variety of ailments. If you choose to participate in a clinical trial, you could be helping many people in the future to enjoy better health and live longer.

If you are interested in participating in a clinical trial, contact a company such as Quintiles to see if you qualify.