TL;DR:
European sites can be more cost efficient than US sites, particularly for Phase I trials, which have consistently cost up to 40% less than equivalent trials conducted in the US. The exact difference depends on the country, the protocol, the therapeutic area, and which costs the local health system absorbs.
Some of the biggest cost differences in early-phase programs come from the sites. We carried out two similar studies in two sites. In the United States, the sponsor paid site fees of roughly $50,000 per patient over a two-and-a-half-month participation period, plus approximately $6,000 in patient compensation. In Austria, the equivalent site cost was roughly $12,000 per patient.
EU vs. US: What does first-in-human evidence cost? →
However, cost should never decide where a trial runs by itself. A cheaper site with the wrong patient population or weak recruitment potential can cost more in delays than it saves in fees. Patient availability, investigator experience, data quality and site readiness often matter more than cost because poor recruitment can quickly erase the savings from a lower site budget.
That is why we always recommend a structured feasibility review before selecting a site or country. A site or region already recruiting for several overlapping or competing studies may have a much smaller realistic patient pool than its headline feasibility numbers suggest. Identifying that competition before contracting gives the sponsor an opportunity to select another site while changing course is still inexpensive.
In most jurisdictions, continued access to a proven intervention after a trial ends is an ethical expectation enforced by the ethics committee.
Brazil is the clearest exception. Brazil’s Law No. 14,874/2024 makes post-trial access a legal obligation. The sponsor must provide free access to the investigational drug after the study ends if it remains the participant’s best therapeutic option. The obligation ends only under conditions set out in the law, such as the drug becoming available in the public health system or five years passing after its commercial launch in Brazil. Before the trial starts, the ethics committee must validate a post-trial access plan.
Sponsors should raise this during site feasibility. A generic per-patient cost comparison will not surface it, and finding it during ethics review is too late.
Sponsors need a defined molecule, a working hypothesis about the indication, and an initial pharmaceutical quality strategy before thinking on geography.
This is because trial feasibility should consider the protocol, target population, geography, operational requirements, and realistic recruitment potential before individual sites are selected. Location comes later, once the sponsor knows what the trial must prove and in which population.
The table below summarizes the factors that belong in the decision.
| Factor | Question to answer before selecting a location |
|---|---|
| Patient population | Does the country provide access to the population the future submission or market access will need? |
| Investigator experience | Do qualified investigators with relevant GCP experience operate at the candidate sites? |
| Regulatory timeline | What is the realistic approval window for this specific member state or the FDA, including possible requests for information? |
| Site cost structure | Does the sponsor have to provide standard care or is it covered by the health system in the country? |
| Post-trial legal obligations | Does this country's law bind the sponsor to a post-trial access or continued supply obligation, and for how long? |
| Future FDA relevance | If this data may later support a US submission, does the population and study design meet expectations under 21 CFR 312.120? |
| Competing enrollment | Are other sponsors currently running trials at the candidate sites for the same or an overlapping population? |
If you are weighing this decision for your own program, a free Expert Hour gives you a direct conversation about your molecule, population, regulatory pathway, and timeline rather than a generic answer.
Gouya Insights supports early-stage sponsors with strategic planning, from indication and country selection to clinical development and regulatory strategy.
Not necessarily. FDA can accept qualifying foreign clinical data generated outside an Investigational New Drug application, provided the study meets the requirements of 21 CFR 312.120.
What matters is designing the European program with the future US submission in mind from the first protocol draft, not after the data already exist. That means thinking early about the patient population, endpoints, documentation, data integrity, and whether discussion with FDA before the study would reduce later regulatory risk.
CTIS coordinates review across participating EU Member States through a single application, while the FDA IND process runs through one national regulator. The comparison is not simply 30 days for FDA versus 60 days for CTIS, because those timelines cover different stages of review.
In the EMA region, regulatory and ethics assessments sit within a coordinated statutory process. The initial CTIS application timeline is 60 days, with possible extensions of up to 15 days during validation and up to 31 days when assessment questions are raised, even in the worst case.
In the US, FDA’s 30-day review applies only to the first IND submission. FDA has no set deadline for reviewing later changes to the protocol. Approval from the institutional review board (IRB) usually takes 4 – 8 weeks, and Gouya Insights has seen some IRB reviews take several months. In the EU, changes submitted through CTIS have fixed legal deadlines.
About the Author
PD Dr. Ghazaleh Gouya-Lechner is the founder of Gouya Insights and a cardiologist with over 20 years of hands-on clinical practice. She has worked across clinical development, regulatory strategy, and pharmacovigilance for both pharmaceutical and medical device companies. In 2017 she founded Gouya Insights, a CRO supporting early-stage biotech and medtech companies through clinical trials and drug development.
Frequently Asked Questions
Does a European trial delay FDA approval later?
Not simply because it was conducted in Europe. FDA can accept qualifying foreign clinical data generated outside an IND when the requirements of 21 CFR 312.120 are met, including good clinical practice and appropriate supporting documentation.
Can a sponsor split a first trial across the US and Europe?
Yes. A common approach is to run the Phase I trial in healthy volunteers in Europe, then move to the US for later trials in the target patient population. Sponsors that take this route should confirm early that the European data will meet FDA expectations for the US program.
What is the single biggest mistake founders make in this decision?
Selecting a location primarily on cost or an existing investigator relationship without a structured feasibility review of patient availability, site capability, competing enrollment, and the future regulatory pathway.
References
Nora holds degrees in law from Janus Pannonius University and in pharmacy from Semmelweis University, combining legal and scientific expertise. She is a certified Data Protection Officer with hands-on experience supporting GDPR compliance and contractual safeguards for biotech and pharma clients. With over 20 years in clinical research, she brings a pragmatic, risk-aware approach to data protection in global trials
