Clinical Research - Therapeutics

A General Overview of Medical Product Clinical Investigations

Before pharmaceutical or biologic products become available to the public, clinical studies must be conducted to ensure that these products are safe and efficacious. These studies, also called trials, involve human participants. There are four main types of studies involved in the medical product development process: Phase I, II, III, and IV. The type of study that needs to be conducted depends on the stage of development, the type of marketing application, as well as the complexity and risks associated with the product on consumers.

Considerations for Drug Substances/Generic Drugs Clinical Trials

  • Phase I and II are conducted post-Investigational New Drug Application (IND) approval.
  • Phase III studies are used for New Drug Applications (NDAs) and Abbreviated New Drug Applications (ANDAs).
  • Studies for marketing approval of generics must demonstrate bioavailability or bioequivalence to the reference drug, often a brand-name drug. These studies can include animal studies or clinical trials but they are not always required.

Considerations for Biologics/Biosimilars Clinical Trials

  • Clinical trials for biosimilars sometimes occur after the completion of analytical and animal studies to further address any clinically meaningful differences between the proposed biosimilar and reference biologic i.e., investigating pharmacodynamics and pharmacokinetics of the biosimilar in study participants.
  • The FDA permits risky gene therapy trials involving the pediatric population, provided that the IRB can demonstrate that the risks of the trial are only slightly higher than the minimal risk of the investigation itself. This process is outlined in CFR 50.54 by the FDA.

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Online database of clinical research studies in the US and 200 other countries
EudraCT European Union Drug Regulating Authorities Clinical Trial Database
International Clinical Trials Registry Platform (ICTRP) International Clinical Trials Registry Platform

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