The study, published in The Lancet Regional Health – Europe by a team of researchers affiliated with the European Medicines Agency and national regulatory authorities, is the first to stitch together data from the EU’s two clinical trial registries into a single harmonised dataset. The authors extracted records from the legacy EudraCT database, which operated under the Clinical Trials Directive from 2004 until 2022, and from the Clinical Trials Information System, or CTIS, the centralised portal launched under the successor Clinical Trials Regulation. After applying strict eligibility criteria to 55,052 retrieved records, the final analytical dataset comprised 25,320 authorised trials initiated between 1 January 2013 and 31 December 2025.

The technical challenge of merging the two systems was considerable. Under the old Directive, public disclosure was limited to a subset of information on authorised trials, and adult phase I trials were entirely invisible unless they involved children or formed part of a paediatric investigation plan. The new regulation swept those restrictions away, mandating publication of every assessed trial with legally binding timelines. To make the two periods comparable, the researchers excluded adult phase I trials not linked to paediatric plans, removed trials conducted exclusively in the United Kingdom following Brexit, and carefully deduplicated transitioned studies that had migrated from EudraCT into CTIS, assigning them their original authorisation dates to avoid double counting.

The headline numbers tell a story of stability, disruption and contraction. Between 2013 and 2019, the EU/EEA authorised a steady average of around 1,989 trials per year. Activity then surged during the pandemic, peaking at 2,364 trials in 2021 as researchers raced to test vaccines and therapeutics and as delayed non-COVID studies resumed. From 2022 onwards, however, annual counts settled at an average of just 1,721 trials. The authors caution that part of this decline may represent a correction after exceptional pandemic conditions and adjustments to the new regulatory framework, but they note that the persistence of lower volumes through 2025 suggests deeper structural forces are at work, including the global redistribution of clinical research toward Asia and the post-pandemic contraction in biopharmaceutical investment.

The composition of European research is changing as much as its volume. Phase IV trials, which monitor medicines after market approval, shrank from about 20.5 percent of all authorisations to 13.7 percent between the two periods, while multi-phase trials combining stages such as phase I–II or II–III nearly doubled their share from 8.9 percent to 16.5 percent. Phase II trials remained the most common category at roughly 37 percent of authorisations, followed by phase III trials at 32 percent. The authors suggest that the rise of multi-phase designs may reflect more integrated development programmes using adaptive designs, in which a single application covers multiple research objectives, potentially reducing the count of distinct registered trials even as scientific output continues.

Perhaps the most troubling finding concerns who is sponsoring European trials. Before the pandemic, commercial and non-commercial sponsors were almost evenly matched, averaging 1,024 and 956 trials per year respectively. After 2022, commercial activity fell modestly to 941 trials per year, a reduction of 8.1 percent, while non-commercial activity plummeted to 778 trials per year, an 18.6 percent drop. Academic sponsors, the analysis shows, remain overwhelmingly mononational, with only about 9 percent of their trials spanning multiple countries, whereas commercial sponsors now run more than three-quarters of their trials across several European states. This asymmetry points to well-documented structural barriers facing academic researchers, including fragmented funding, heavy regulatory compliance burdens, limited operational infrastructure and difficulties in procuring and manufacturing investigational products for multinational studies.

Therapeutic priorities have shifted markedly over the thirteen-year window. Cancer remains the dominant research area, accounting for 25.2 percent of all authorised trials, followed by nervous system diseases at 7.5 percent and cardiovascular diseases at 6.5 percent. But trials targeting immune system diseases nearly tripled their share, from 3.3 percent in 2013 to 9.4 percent in 2025, making them the second most researched area since 2024. Viral disease research spiked dramatically during the pandemic, reaching 14.5 percent of trials in 2020 before falling back to baseline. Meanwhile, research into rare diseases intensified, rising from 17.1 percent of trials in the earlier period to 20.3 percent after 2022, and the proportion of trials including elderly participants climbed steadily from 68.7 percent in 2013 to a peak of 81.4 percent in 2025.

The molecular character of European research is also evolving. Trials involving biologic medicines, produced from or containing biological substances, rose from 35.1 percent of authorisations in 2013 to 49.1 percent in 2025, approaching half of all European clinical research. Advanced therapy medicinal products, which include gene therapies, somatic cell therapies and tissue-engineered products, grew from 3.2 percent to 4.0 percent of trials, with gene therapy emerging as the fastest-growing modality within the category. Intriguingly, the analysis also reveals that Europe occupies a distinctive position in the global landscape: phase I trials make up only about 18 percent of authorised EU/EEA trials, compared with roughly 40 percent of global trial starts in 2024, while nearly half of European trials are multinational, spanning an average of six Member States, in contrast to a worldwide trend toward single-country studies.

European regulators are not standing still. The Accelerating Clinical Trials in the EU initiative has established two quantitative performance targets: authorising an additional 500 multinational trials over the next five years and ensuring that at least two-thirds of trials recruit their first patient within 200 days of application. In January 2026, the Heads of Medicines Agencies launched FAST-EU, a coordinated fast-track approach designed to bring greater predictability and speed to multinational trial authorisations. The study’s authors argue, however, that these ambitions may fall short without targeted support for the academic sector, whose predominantly national footprint stands in stark contrast to the multinational goals. They point to complementary initiatives, including the revision of the EU’s pharmaceutical legislation, the recently proposed EU Biotech Act, and funding programmes such as Horizon Europe and ERA4Health, as vehicles for building the operational capacity academic sponsors need.

The study is not without limitations, which the authors address candidly. The exclusion of adult phase I trials, though necessary for comparability, means the reported figures understate total trial activity, although an unpublished analysis including non-public phase I data corroborated the observed decline. A small number of authorised CTIS trials were temporarily hidden from the public portal under confidentiality rules, requiring internal EMA data to complete the picture. Classification of therapeutic areas relied on MeSH codes, which may fragment some conditions across categories, and structural differences between the two registries demanded custom mapping of definitions, particularly for biologic therapies. Still, the analysis establishes something the European research community has lacked: a reproducible, transparent framework for monitoring clinical trial activity across regulatory eras, built entirely on public data. As Europe fights to retain its place in a global research order increasingly shaped by China-headquartered sponsors and shifting investment flows, that foundation may prove as valuable as the findings themselves.

Subject of Research: Longitudinal trends in clinical trials of medicinal products in the EU/EEA from 2013 to 2025 based on harmonised EudraCT and CTIS registry data

Article Title: Clinical trials on medicinal products in the EU/EEA, 2013–2025: a cross-sectional analysis of CTIS and EudraCT data

Article References: Machado, T., Capone, G., den Rooijen, I., Bindt, F., Marcelino, M., van Wyk, J., Zanoletty Perez, A., Pioppo, L., Santos Ivo, R., & Arlett, P. (2026). Clinical trials on medicinal products in the EU/EEA, 2013–2025: a cross-sectional analysis of CTIS and EudraCT data. The Lancet Regional Health – Europe, 71, Article 101884. https://doi.org/10.1016/j.lanepe.2026.101884

Image Credits: AI Generated

DOI: 10.1016/j.lanepe.2026.101884

Keywords: clinical trials, EU/EEA, CTIS, EudraCT, Clinical Trials Regulation, European Medicines Agency, non-commercial sponsors, multinational trials, biologic medicines, advanced therapy medicinal products, rare diseases, pharmaceutical policy