Investigational medicinal product

Investigational Medicinal Product (IMP) refers to a pharmaceutical form of an active substance or placebo being tested or used as a reference in a clinical trial, including a product with a marketing authorization when it is used or assembled (formulated or packaged) in a way different from the approved form, or when used for an unapproved indication, or when used to gain further information about the approved form. IMPs are central to the development of new drugs and therapies, providing critical data on efficacy, safety, and optimal use.

Definition and Purpose

An Investigational Medicinal Product is defined by regulatory authorities, such as the European Medicines Agency (EMA) and the Food and Drug Administration (FDA), as a substance or combination of substances under investigation in a clinical trial. The primary purpose of an IMP is to discover or verify the clinical, pharmacological, or pharmacodynamic effects of an investigational product, to identify any adverse reactions, or to study the absorption, distribution, metabolism, and excretion of the products with the aim of ascertaining their safety and efficacy.

Regulation and Authorization

The development and use of IMPs are highly regulated. In the European Union, the Clinical Trials Regulation (EU) No 536/2014 outlines the requirements for authorization, conduct, and reporting of clinical trials involving IMPs. Similarly, in the United States, the FDA regulates the use of investigational drugs under the Investigational New Drug (IND) application process. These regulations ensure that clinical trials involving IMPs are conducted in accordance with ethical principles and scientific standards, protecting the rights, safety, and well-being of trial participants.

Manufacturing and Labeling

Manufacturing of IMPs must comply with Good Manufacturing Practice (GMP) to ensure their quality and consistency. This includes rigorous testing and documentation at every stage of the manufacturing process. Labeling of IMPs is also subject to strict regulations, which require that the label provides sufficient product information, including the statement that the product is for investigational use only.

Clinical Trial Phases

Investigational Medicinal Products undergo several phases of clinical trials to assess their safety and efficacy:

• Phase I trials are the first stage of testing in human subjects, primarily focused on assessing the safety, tolerability, pharmacokinetics, and pharmacodynamics of an IMP.
• Phase II trials aim to evaluate the efficacy of the IMP for a particular indication, along with further safety assessment.
• Phase III trials involve a larger group of participants to confirm the IMP's efficacy, monitor side effects, compare it to commonly used treatments, and collect information that will allow the IMP to be used safely.
• Phase IV trials are conducted after the IMP has been marketed to gather additional information on the drug's effect in various populations and any side effects associated with long-term use.

Ethical Considerations

The development and testing of IMPs involve ethical considerations, particularly regarding the informed consent of participants, the risk-benefit ratio of the investigational product, and the necessity to ensure that clinical trials are conducted in a manner that respects the rights and safety of participants.

Conclusion

Investigational Medicinal Products play a crucial role in the advancement of medical science and the development of new therapies. Through rigorous testing and regulation, IMPs have the potential to become approved medications that can improve health outcomes and quality of life for patients around the world.