Clinical Trials

In the ever-growing world hurled with complex challenges; new or better therapies have to be made accessible to a patient’s treatment, prevention &/or cure. Prior to being launched into the market where patients could reap the benefit, potential therapies such as drugs, biologics or devices discovered in the R&D phase have to endure the clinical trials pathway. Clinical trials broadly entail testing and analyzing potential treatments in humans for safety and efficacy parameters; confirming its intended purpose and further marketing for use in larger populations. These potential therapies are experimented on animals first, previous to testing in humans, to determine the levels of toxicity and thereby minimizing the risks in human studies.

The US FDA is the main regulatory authority devoted to ensuring proper safety of human subjects participating in these clinical trials. The potential new therapy is often compared to an existing one, and to a placebo which doesn’t contain any active component. Although these studies are intended for the benefit of the patient, it may do as well as harm and hence the subjects ought to be informed about the risks associated with the trial and be consented. Based on certain eligibility parameters, clinical trials are conducted on either patients or healthy volunteers.

Clinical Development cycle

Development Phase

Phases of Development

Clinical trials consist of broadly four phases which are well-defined by the industry and regulatory authorities:

Phase I

This is the initial phase where a potential therapy is tested on a small group of individuals to primarily assess and ensure safety issues. Several critical characteristics are determined during this phase which indicates whether a body can tolerate the experimented dosage and therapeutic value be obtained.

Phase II

If a potential treatment is found to be safe in phase I, approval will be sought to escalate the desired therapy in a larger population for further analyzing its efficacy. During this phase, suitable dosage levels are determined. Also, double-blinded studies are conducted wherein neither the patient nor investigator is aware which individuals have received placebo or actual drug that is being studied. A placebo is provided in order to eliminate biases that occur in a study and ensure correct reporting of results.

Phase III

Based on the positive outcomes in Phase II, a study may be continued into Phase III trials which involves study in a much larger population ranging from hundreds to thousand volunteers. This phase focusses on safety and efficacy parameters in patients and identifies the possibility of any side effects. Results of the potential therapy are compared to existing therapy in this phase and establish whether benefits outweigh the risks.


Filing a request for registration with the US FDA is the next process in drug development phase. The potential new therapy is thoroughly assessed based on all the information collected from all the three trial phases. Once approval is granted by the regulatory authorities, the potential drug may be marketed for use.

Phase IV

Also known as the Post Marketing Approval, this phase majorly focusses on studying the consequences of drugs in general population for a longer duration thereby providing information on safety, efficacy, and side-effects.

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