A trial site, called a clinical trial site in the EU Clinical Trials Regulation, is the hospital, outpatient clinic or practice where participants in a clinical trial are enrolled, treated and examined. The investigator is responsible on site, and where there are several investigators at one site, the principal investigator leads the team. Site management covers all the tasks needed to find these sites, contract them, prepare them and support them until the trial is completed. It is offered by contract research organisations, by so-called site management organisations (SMOs), which support sites with their own trial staff, and by trial networks.
What it is about
Selection, contracting, preparation, recruitment and support of the hospitals and practices where your trial runs.
Who selects
The sponsor. Under ICH E6(R3) it is responsible for choosing suitable investigators and institutions.
What is assessed
The suitability of investigator and site is part of Part II of the application and is assessed in Germany by the ethics committee.
What is new
Since December 2025 there have been standard contractual clauses for the contract with the trial site in commercial trials.
How well a trial progresses depends heavily on the choice of sites. A site that does not reach the promised number of participants extends the duration and still ties up resources for initiation, monitoring and close-out. Site management therefore aims to assess realistically during selection what a site can deliver, and then to support it so that recruitment and data quality are right.
When you need this
The need arises mainly for sponsors that have no clinical operations department of their own or want to run a trial in a country where they have no contacts with hospitals. In rare diseases, where suitable patients are treated at only a few specialised centres, a partner who knows these centres is also worthwhile. Conversely, hospitals and practices use the support of an SMO when they lack trial staff, for example study nurses or coordinators who schedule visits, maintain documents and enter data.
Another occasion is a trial that is not recruiting as planned. The task is then to find the causes at the existing sites and, if necessary, to add new sites. Because adding a site and changing a principal investigator count as substantial modifications under the Regulation that require authorisation, this step should be planned early.
Legal basis and rules
Regulation (EU) No 536/2014, Articles 49 and 50
The investigator must be a medical doctor as defined in national law or a person following a profession recognised in the Member State as qualifying for this role. Other individuals involved must be adequately qualified by education, training and experience, and the site must be suitable for conducting the trial.
Annex I of the Regulation
For each Member State, the documents to be submitted include the list of trial sites with principal investigators and the planned number of participants, the investigators’ CVs, a duly justified statement on the suitability of the site, the recruitment arrangements and information on the compensation of the trial sites.
Part II and German Medicines Act (Arzneimittelgesetz, AMG) § 40
Each Member State itself assesses the suitability of investigators and sites, recruitment, and the compensation of participants and investigators. In Germany, the competent ethics committee performs these tasks.
AMG § 42d and StandVKlV
The Standard Contractual Clauses Ordinance (Standardvertragsklauselverordnung, StandVKlV) sets out clauses for contracts between sponsor and trial site. It applies to contracts concluded after 17 December 2025, but not to trials by non-commercial sponsors.
ICH E6(R3)
Describes the duties of investigator and sponsor, for example demonstrating recruitment potential, sufficient staff and time, documented delegation of tasks, and the selection, initiation, support and close-out of sites by the sponsor.
The investigator remains responsible
An investigator may delegate tasks to other persons or service providers, including SMO trial staff. Under ICH E6(R3), however, the investigator retains ultimate responsibility, must supervise those involved appropriately and must ensure that they are qualified and informed about the protocol and the investigational medicinal product. Who takes on which task is documented, and the agreements with such service providers must be recorded in writing.
How the work is organised
The services follow the life cycle of a trial site. Depending on the assignment, the service provider takes on all steps or only some of them:
01
Feasibility and selection
Potential sites receive the protocol and the investigator’s brochure and estimate how many suitable participants they can enrol in the agreed period. Experience, staff, equipment, laboratories and competition from other trials are also assessed.
02
Documents for the application
For Part II, CVs, the statement on the suitability of the site, the description of the recruitment arrangements including advertising material, and the information on the compensation of participants and sites are compiled.
03
Contract and budget
The contract covers, among other things, compensation, rights to results, publications, data protection, audits and inspections, archiving and termination. In commercial trials, the standard contractual clauses form the basis.
04
Initiation
Before the start, the site team is trained on the protocol, the investigational medicinal product and their respective tasks, the delegation is recorded and the equipment is given a final check.
05
Recruitment and ongoing support
During the trial, recruitment and retention of participants are tracked, the site’s questions are answered and problems are addressed early. Monitoring checks whether consent forms are in place, events are reported on time and documents are kept complete.
06
Close-out
At the end, the return or destruction of the investigational medicinal products is settled and the archiving of the essential documents is arranged. The sponsor notifies the end of the trial via the EU portal within 15 days.
The Regulation also sets deadlines here: the sponsor notifies the start of the trial, the first visit of the first participant and the end of recruitment within 15 days for each Member State concerned. A service provider that supports the sites should deliver these dates reliably so that the notifications are made on time.
What to look for when choosing a provider
Whether a provider is right for site management can be seen above all from how reliable its statements about sites and recruitment are. These questions help when comparing providers:
Questions to ask the provider
Which sites in your indication has the provider already worked with, and how did they recruit?
How is feasibility assessed: on the basis of actual patient numbers or only on self-reporting?
Does the provider place its own trial staff at the sites, and how is their inclusion in the delegation arranged?
Does it have experience with contracts based on the standard contractual clauses and with the documents for Part II?
How is recruitment tracked, and at what point does it take corrective action if a site falls behind plan?
How are payments to the sites handled and documented?
Who is your contact person if problems occur at a site, and how quickly will you hear about them?
How are close-out and archiving organised, including when an investigator leaves the site?
Frequently asked questions
Do we have to use the standard contractual clauses?
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For contracts between a commercial sponsor and a trial site concluded after 17 December 2025, § 42d AMG provides for their use, unless both parties expressly agree otherwise. Placeholders must be filled in and the alternatives provided must be selected. The Ordinance does not apply to non-commercial sponsors.
Can we add further sites during the trial?
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Yes, but under Article 15 of the Regulation adding a site counts as a substantial modification and may only be implemented after authorisation. The same applies to changing a principal investigator. You should allow for this time before recruitment becomes critical.
May we recruit participants through advertisements?
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Yes, provided the procedure is described in the application. Advertising material such as adverts, posters or spots is submitted with the application, together with an explanation of how responses and unsuitable applicants are handled.
Who is liable for errors by SMO staff at the site?
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Liability is governed by the contracts. Under Good Clinical Practice, however, the investigator remains responsible for the proper conduct of the trial on site, including for tasks they have delegated. Responsibilities, training and supervision should therefore be set out in writing.
Sources
Every statement in this text was checked against these primary sources (as of 10.11.2026). Laws, guidelines and authority websites, no advertising.
Conreso GmbH, based in Munich, is a contract research organisation for clinical trials in Phases II to IV, with a focus on paediatrics, oncology and vaccine trials. Its services include study planning, monitoring and biometrics.
München
Evidenced
„Identifikation und Rekrutierung geeigneter Prüfzentren“
GWT-TUD GmbH, based in Dresden, is a knowledge and technology transfer service provider. It offers strategic management of clinical trials as sponsor or CRO, as well as project management for industrial projects.
Dresden
Evidenced
„Die GWT bietet einen ganzheitlichen Ansatz zur Erhöhung der Sichtbarkeit Ihrer Studien, effektive Identifizierung und Rekrutierung von Studienzentren und Teilnehmern.“
Pratia Germany GmbH, based in Hamburg, operates a network of six research sites in Germany for clinical trials in Phases Ib to IV. The company also provides site service provision for sponsors and CROs.
Hamburg
Evidenced
„Pratia Germany provides comprehensive Site Service Provision (SSP), supporting Sponsors, CROs, hospitals, and research sites with experienced clinical research professionals while allowing sites to retain full operational oversight.“
Symbio Clinical Research GmbH in Münster is part of the Symbio Group, a CRO for clinical trials in dermatology, aesthetics, gastroenterology and inflammatory diseases.
Münster
Evidenced
„Strong site network built on relationships with the very best dermatology, aesthetics, gastroenterology, and inflammation sites, allowing for easy site selection“