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Public Health

Clinical trials

Clinical trials are scientifically controlled studies undertaken in humans to establish or confirm the safety and effectiveness of investigational medicinal products (IMPs). The conduct of clinical trials in the EU is currently governed by the Clinical Trials Directive and the Clinical Trials Regulation, became applicable on 31 January 2022. 

A phased transition will happen over 3 years, and all the organisations that set up clinical trials will have enough time to make sure that the trials ongoing trials are progressively transferred to the rules of the Regulation, at the latest by 31 January 2025.

The aim of the Clinical Trials Regulation is to ensure a greater level of harmonisation of the rules of conducting clinical trials throughout the EU. It features:

  • A streamlined application procedure for all clinical trials conducted in Europe via a single EU portal and database. All applicants must be registered before submission of a clinical trial application.
  • A single authorisation procedure for all clinical trials, to allow a faster and more thorough assessment by all concerned EU countries
  • The extension of the silent agreement principle to the authorisation process giving more legal certainty to sponsors and researchers, in particular SMEs and academics
  • Strengthened transparency for clinical trials data

Transition from the Clinical Trials Directive to Regulation

Until the Clinical Trials Regulation EU No 536/2014 became applicable, all clinical trials performed in the European Union are required to be conducted in accordance with the Clinical Trials Directive. This Directive is repealed on the day of entry into application of the Clinical Trials Regulation. It will however still apply three years from that day to:

  • Clinical trials applications submitted before 31/1/2022
  • Clinical trials applications submitted before 31/1/2023, if the sponsor opted to submit according to the Clinical Trials Directive.

The Commission's GCP Directive will apply to clinical trials submitted under the Clinical Trials Directive until 31/1/2025, except for the provisions in chapters 5 and 6 of this Directive which are related to inspectors and inspection procedures. These aspects will be covered by the Implementing Regulation (EU) 2017/556 of 24 March 2017 on detailed arrangements for the good clinical practice inspection procedures pursuant to Regulation (EU) No 536/2014 of the European Parliament and of the Council, which will become applicable at the same time as Regulation (EU) No 536/2014 and will apply to all GCP inspections (this means, inspections of clinical trials conducted under the Regulation as well as the Directive).

The Commission GMP Directive will be repealed by the new Commission GMP Directive 2017/1572 on 31/1/2022 (i.e. the date of entry into application of the Clinical Trials Regulation).

The Commission Delegated Regulation (EU) 2017/1569 of 23 May 2017 supplementing Regulation (EU) No 536/2014 will apply, as a matter of principle, to all clinical trials as 31/1/2022. It specifies principles and guidelines for good manufacturing practice for investigational medicinal products for human use, and arrangements for inspections.

During the transitory period (i.e. until 31/1/2025), EU countries may however continue to apply their national law, adopted in order to transpose Directive 2003/94/EC, to those clinical trials conducted under the Directive 2001/20/EC. Additionally, the detailed Commission guideline, adopted on 8 December 2017, on the good manufacturing practice for investigational medicinal products, pursuant to the second paragraph of the Article 63(1) of Regulation (EU) No 536/2014 will become applicable on 31/1/2022 as well.

Lastly, Commission Implementing Regulation (EU) 2022/20 of 7 January 2022, laying down rules for the application of Regulation (EU) No 536/2014 of the European Parliament and of the Council as regards setting up the rules and procedures for the cooperation of the Member States in safety assessment of clinical trials, will also become become applicable on 31/1/2022.

The Commission and Member States meet regularly in the Expert Group on clinical trials to discuss the implementation of the Clinical Trials Regulation. Agendas and minutes from the meeting are published on the Commission Register of Expert Groups.

Guidelines on the conduct of Clinical Trials

The guidelines for the application of Clinical Trials Directive can be found in Eudralex Volume 10. A number of relevant guidelines and recommendations have been revised and updated in line with the changes and requirements of the Clinical Trials Regulation. All relevant documents will be progressively updated.

The Heads of Medicines Agencies established the Clinical Trials Facilitation and Coordination Group ("CTFG") (in which the Commission and EMA are observers), in order to discuss ongoing technical issues.

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