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Phases of clinical development

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Index

1 Introduction
2 Phases of clinical development

Introduction

The diagram below explains the four phases of Clinical Development.

Phases of clinical development

A diagram explaining the details of the four phases of clinical development in terms of their objectives and features. Phase I, also known as ‘First in Human’, covers human pharmacology. The objectives of this phase are: Safety and tolerability, Pharmacokinetics (ADME), and Pharmacodynamics. The features are: Small number of participants (n = 20-100), normal healthy volunteers (seldom patients), specialised centres, and open-label. Phase II is the therapeutic exploratory phase. The objectives of Phase II are to discover therapeutic effect, optimal dose, safety (toxicity), and proof of concept. The features of Phase II are: First in patients with disease (n = 100-500), medical institutions and private practice, open-label, blinded, comparative, multi-dose. Phase III is the therapeutic confirmatory stage. The objective of Phase III is the confirmation of efficacy and safety. The features of Phase III are: Large studies (n = 1000- >5000), medical institutions and private practice, multi-centre, blinded, and comparative. Phase IV is also known as Post-approval and Life-cycle management. The objectives of Phase IV are: real-life data, safety surveillance (pharmacovigilance), and therapy optimisation of approved medicines. The features of Phase IV are: Very large numbers of patients, long-term evaluations, and further development (e.g. new indications). — Phases of clinical development

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Glossary terms referenced in article:

Clinical development