Clinical trials are vital for advancing medical knowledge and improving patient care. However, conducting trials in different regions, such as the European Union (EU) and the United States (US), involves navigating unique regulatory frameworks and cultural factors. In this blog post, we will explore the nuances in the EU and US clinical trial markets, focusing on study design and protocol development, patient recruitment, prescreening, consent, and patient engagement.

Study design and protocol development 

The EU and US differ in their approach to study design and protocol development. In the EU, guidelines provided by the European Medicines Agency (EMA) promote consistency across member states. On the other hand, the US allows for more flexibility since it only has one overarching federal agency, the Food and Drug Administration (FDA), which enables sponsors to design trials tailored to their specific needs. However, both regions prioritise scientific rigour, patient safety, and ethical considerations when developing study protocols.

Patient recruitment

Patient recruitment is a critical aspect of clinical trials, and the EU and US employ different strategies. In the EU, due to its size and diversity, researchers have access to a larger population pool, which can facilitate participant recruitment. Additionally, the EU's centralised healthcare systems enable easier identification and referral of potential participants. In contrast, the US has a more fragmented healthcare system, which can make patient recruitment more challenging. Sponsors often employ a combination of strategies, such as working with clinical research organisations (CROs) and leveraging digital platforms, to overcome recruitment hurdles.


Prescreening is the process of evaluating potential participants for eligibility criteria before enrollment. In the EU, prescreening may involve accessing centralised healthcare databases or collaborating with healthcare professionals to identify suitable candidates. Conversely, in the US, the Health Insurance Portability and Accountability Act (HIPAA) imposes strict regulations on the use and sharing of patient data. Therefore, sponsors must navigate privacy concerns and seek informed consent when accessing medical records for prescreening purposes.

Informed consent 

Obtaining informed consent is crucial to protect participants' rights and ensure ethical conduct. In the EU, consent processes often follow the principles outlined in the EU Clinical Trials Regulation. This involves providing trial information to participants and obtaining written consent before enrollment. In the US, consent processes for medical research studies are governed by the Code of Federal Regulations (CFR), specifically Title 45, Part 46, also known as the “Common Rule.” The CFR’s required consent process typically involves a more extensive documentation process compared to other countries. For instance, when enrolling participants in a clinical trial, researchers are required to provide detailed information about the study, including its purpose, potential risks and benefits, procedures involved, alternative treatments, confidentiality measures, and any financial considerations. Cultural differences can also influence the understanding and sentiment of informed consent, so researchers should tailor their approach accordingly.

Patient engagement 

Engaging patients throughout the clinical trial process is essential for ensuring retention and overall trial success. In the EU, patient engagement efforts often involve patient advocacy groups, which play a crucial role in trial design and communicating study-related information. In the US, advocacy groups play a role, but patient engagement is also driven by initiatives like the Patient-Centred Outcomes Research Institute (PCORI), which aims to involve patients in research decision-making. Both regions recognise the value of patient input in shaping trials but employ different approaches to achieve meaningful patient engagement.


The EU and US clinical trial markets exhibit distinct nuances in study design and protocol development, patient recruitment, prescreening, consent, and patient engagement. Understanding these differences is crucial for researchers, sponsors, and regulatory authorities to navigate the complexities of conducting trials in each region.

The Sano platform helps accelerate trials by combining genetic testing, recruitment, and long-term engagement all in one place for faster enrollment and simplified operations even across borders. If you'd like to find out more about how Sano Genetics can support your research study, visit our Sponsors page or get in touch below.

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