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Types of Studies

TypesOfStudiesThe OPRC Program is conducting different types of studies to learn more about how medications and supplements are processed by the body during pregnancy. Below is a short description of common research terminology, including each type of study.

Basic/Translational Research: This term refers to research that does not involve human research participants, but whose purpose is to increase understanding of a disease or condition in order to promote research in humans. Examples are animal studies, studies involving cells, and computational and system modeling.

Opportunistic Study: The term “opportunistic” in study design refers to adding a research goal to an intervention that is already being conducted as standard of care. For instance, an example would be drawing blood from a pregnant woman who is already being prescribed a medication by her care provider, for the purpose of studying its pharmacokinetic/pharmacodynamics.

Pharmacodynamics (PD): Often conducted in tandem with pharmacokinetics during a Phase I or II study, PD is the study of what the drug does to the body. More complexly put, PD is the relationship between the concentration of the drug in the body and the biological or physiological effects of the drug on the body or on other organisms in the body (such as bacteria).

Pharmacokinetics (PK): Often conducted in tandem with pharmacodynamics during a Phase I or II study, PK is the study of what the body does to the drug. Commonly studied measures are how fast and how completely the drug is absorbed into the body, how the drug is distributed throughout the body, to what extent the drug is metabolized, and how rapidly the drug is eliminated from the body.

Phase I: These are small, short-term studies who primary purpose is to assess the safety of a drug. Phase I studies are typically conducted with healthy volunteers, though patients with the medical condition under study are sometimes recruited. In OPRC studies, a Phase I trial may include pregnant women who are already being prescribed the medication by their care provider. The goal is to determine the drug’s most frequent and serious adverse effects, and often, how the drug is metabolized and excreted. These studies usually have 20 to 100 study participants.

Phase II: These are studies that gather preliminary data on optimal dosing and effectiveness (whether the drug works in people who have a certain disease or condition), often comparing the drug to a placebo or alternate treatment. These studies also gather additional safety and adverse effects information and usually have up to several hundred study participants.

Phase III: These are larger studies (several hundred to several thousand study participants) that continue to obtain information about safety and effectiveness of the study drug by comparing the drug to a placebo or alternate treatment.

Phase IV: These are studies typically conducted after the drug has received market approval to gather information on the drug's effect in various populations and any safety effects associated with long-term use.

Pilot Study: These studies are smaller in scale, primarily conducted to evaluate feasibility, time, cost, and adverse effects. This preliminary data can be used to determine sample size and the appropriate study design prior to conducting a full-scale research study.