3.5 - Other Considerations3.5 - Other Considerations
Some therapies are not developed in the same manner as drugs, such as disease prevention therapies, vaccines, biologicals, surgical techniques, medical devices, and diagnostic agents.
Prevention trials are conducted in:
- healthy individuals to determine if the therapy prevents the onset of disease,
- patients with early-stage disease to determine if the therapy prevents progression, or
- patients with the disease to determine if the therapy prevents additional episodes of disease expression.
Vaccine investigations are a type of primary prevention trial They require large numbers of patients and are very costly because of the numbers and the length of follow-up that is required.
The objective of a diagnostic or screening trial is to determine if an agent can “diagnose” the presence of disease. Usually, the agent is compared to a “gold standard” diagnostic that assumed to be perfectly accurate in its diagnosis. The advantage of the newer diagnostic agent is less expense or a less invasive procedure.