Types of Clinical Research Studies
Types Of Studies Part 2:
After you have determined whether you want to participate in an In-Patient or Out-Patient, you must decide what you want to test.
Investigational Drug (First in Man):
This is the most common type of study you will see. You will take one or more doses during your stay or Out-Patient visits.
The first time a drug is given to human test subjects, it will more than likely be done as a “Double-Blind” Placebo controlled study. What this means is that not all of the test subjects will receive the study drug. If there are 10 subjects, 6 to 8 will receive the study drug and the remainder will receive a placebo, or inactive substance. “Double-Blind” means that neither you or any of the nurses or technicians will know who is getting the real drug and who is getting the placebo.
Some studies will be done as “open-label” which means that everyone will get the study drug. You will know exactly what you are getting. Typically these are late Phase 1 studies.
Some studies are “bio-equivalency” to compare a generic drug to the brand name drug. You will typically come in for two stays of equal length and take 1 drug during the first stay and the other drug during the second stay with a period in-between for “wash-out”.
Multiple drugs may be tested at one time. You may take one drug for one period and then take another drug for a second period and then take both drugs during a third period. Or you might take one drug for a few days and then add a second drug.
As you can see there are many different dosing scenarios. Be sure to pay attention to the informed consent form. This will outline in detail the drug(s) you will be taking, how they will be administered, how much and when.
Drugs are administered in several ways. The most common are in pill, liquid (oral), skin patch, injection, suppository and intravenous infusion.
Mass Market Drug/Bioequivalence:
These are drugs that are already on the market. Even after a drug is approved by the FDA, further studies may be done. The FDA approves a drug for certain conditions so if the pharmaceutical company wants to market the drug for other uses, then additional trials must be done.
Once a patent to a drug expires (20 to 25 years), competing companies can manufacture generic versions of the drug. These studies are called bioequivalence (bio for short) and compare the brand name drug to the generic drug to ensure the pharmacokinetics are the same (within an acceptable range).
Some drugs are tested with a radioactive element which allows the drugs to appear better in blood, urine and stool collections. The radioactive element is carbon 14 and is given to you in a low dose, usually in a less dose than environmental radiation. The FDA regulates how much radiation can be administered to human test subjects. When you participate in a radio-label drug, you will take one or more doses of the drug without the radioactive element and then one dose with the radioactive element. On this day, you will have multiple blood draws (pk). At this point, you will stop dosing and start urine, stool and daily blood collection. Once the clinic has determined that the drug has been completely excreted from your system via blood, urine and stool, you will be released from the clinic. The amount of days you will spend in the clinic will depend on your body’s metabolism. Each radioactive study is different. The amount of radiation you will receive will vary.
You will see many of these studies as Out-Patient visits. These can range from testing simple things like latex gloves to brain imaging scanners.