Transition trials: CTD to CTR

On this page all relevant information on so-called ‘transition trials’ can be found: clinical trials authorised under the Clinical Trials Directive (CTD) that need to be transitioned to the Clinical Trials Regulation (CTR).


On 31 January 2022 the Clinical Trials Regulation 536/2014 (CTR) came into force with a transition period of three years. Before the end of the transition period, all clinical trials (CTs) authorised under the Clinical Trials Directive 2001/20/EC (CTD [1]) and still ongoing after 30 January 2025 should be transitioned to CTR in time. These so-called transition trials should be registered in the new Clinical Trials Information System (CTIS) and should be approved by all Member States concerned (MSC) before the end of the transition period (31 January 2025). This means a timely submission to CTIS and a submission date preferably not later than 16 October 2024. For submission beyond this date, Member States cannot guarantee a prompt approval. For clinical trials with investigational medicinal products submitted for authorisation in the Netherlands before 1 February 2006 and still ongoing after 30 January 2025, a new clinical trial application should be submitted to CTIS to allow the clinical trial to be continued. In that case, please contact CCMO ( for further information. 

[1] In the Netherlands implemented in the Dutch Act on Medical Research Involving Human Subjects (WMO).

When should the sponsor transition a clinical trial to CTR?

How should a clinical trial be transitioned to CTR?

What is important after the clinical trial has been transitioned?