Clinical Trials

Clinical trials are defined by the FDA as, "trials to evaluate the effectiveness, safety and toxicity of medications or medical devices by monitoring their effects on large groups of people". Clinical trials have to be approved by the IRB and they are an essential part of PMAs. Good Clinical Practices (GCPs) are employed to maintain a regulated approach to clinical trials.

Clinical trials can be categorized into different types based on what they are done for.
1. Treatment trials - These seek to find new treatment approaches or compare to identify the most effective treatment available.
2. Prevention trials - They are done to identify approaches to prevent a specific type of disease from developing in people not exposed to it previously.
3. Early detection/screening trials - They are done to find new ways to identify a specific disease/problem in people even before they develop symptoms.
4. Diagnostic trials - These are done to figure out how new tests or procedures can be used to identify a specific disease in suspected population.
5. Quality of life/ supportive care trials - These trials try to identify ways of improving the comfort and quality of life for people with a disease/problem.

The results of a clinical trial is of much significance. Irrespective of the number of subjects or data involved in a clinical trial, the outcome is usually one of the following four types (in case of treatment trial):

Positive trial ‐ Superior (new treatment is better than standard treatment)
Non‐inferior trial ‐ Equivalence (new treatment is equivalent to standard treatment)
Inconclusive trial ‐ Neither superior nor inferior (new treatment is not clearly better nor clearly worse than the standard treatment)
Negative trial ‐ Inferior (new treatment is worse than the standard treatment)

A clinical trial usually starts with a clear investigational plan and an IRB approval for the study. Some components to be considered in the investigational plan are:
– Clinical study protocol - Study, hypothesis and design; Primary and secondary endpoints; Inclusion/exclusion criteria; Sample size and statistical analysis. It is essential to have a clearly defined and firm study protocol that cannot be changed during the course of the study.
– Risk analysis
– Informed consent form
– Case report forms
– Investigator agreement
– Clinical sites (number of sites / investigators / IRBs)
– Bibliography
– Instructions for Use
– Clinical study duration