Across 98 nephrology Phase II–III trials, the dataset contains 1,635 country-level site allocations, 654 unique site-country institutions, 24 countries, and 13,612 planned participant allocations. Hospital Universitari Vall d’Hebron leads the site ranking with 25 trial appearances, followed by Assistance Publique Hopitaux de Paris with 24. France, Spain, Italy, and Germany form the operational core, accounting for 1,099 of 1,635 site allocations (67.2%) and 9,878 of 13,612 participants (72.6%).
The top 10 sites account for 155 distinct trial-site appearances. Hospital Universitari Vall d’Hebron appears in 25 of 98 trials (25.5%), narrowly ahead of Assistance Publique Hopitaux de Paris with 24 of 98 trials (24.5%).
The leading site list is concentrated in Spain, France, and Germany, suggesting that nephrology feasibility work should start with high-repeat academic and hospital networks rather than broad country coverage alone.
France leads with 367 of 1,635 site allocations (22.4%), followed by Spain with 287 (17.6%), Italy with 257 (15.7%), and Germany with 188 (11.5%). Together, these four countries account for 67.2% of all site allocations.
| Country | Sites | Share | Participants |
|---|---|---|---|
| France | 367 | 22.4% | 3,028 |
| Spain | 287 | 17.6% | 1,870 |
| Italy | 257 | 15.7% | 2,584 |
| Germany | 188 | 11.5% | 2,396 |
| Poland | 108 | 6.6% | 547 |
| Belgium | 53 | 3.2% | 407 |
| Netherlands | 44 | 2.7% | 244 |
| Greece | 42 | 2.6% | 202 |
| Portugal | 38 | 2.3% | 290 |
| Bulgaria | 35 | 2.1% | 183 |
France is the largest site market, but Italy and Germany carry higher participant density than Spain. This makes France and Spain attractive for breadth, while Italy and Germany look stronger for planned enrollment concentration.
Glomerular disease and proteinuric chronic kidney disease (CKD) is the largest site-demand cluster, with 29 of 98 trials (29.6%) and 847 of 1,635 site allocations (51.8%). Broader CKD and renal impairment has fewer sites, 246 of 1,635 (15.0%), but the largest participant allocation, 5,959 of 13,612 (43.8%).
The market splits into two operational models: glomerular/proteinuric trials require broad specialist site networks, while broad CKD programs carry larger patient allocations with comparatively fewer sites.
The top four participant countries are France, Italy, Germany, and Spain. They account for 9,878 of 13,612 country-level participant allocations (72.6%), with France alone contributing 3,028 participants (22.2%).
France is both a site and participant leader, while Italy and Germany over-index on participant allocation relative to site count. Spain contributes more breadth than patient density.
Small molecules dominate the operational footprint, representing 46 of 98 trials (46.9%), 836 of 1,635 site allocations (51.1%), and 9,913 of 13,612 participant allocations (72.8%). Pediatric-flagged trials represent 19 of 98 trials (19.4%) and 380 of 1,635 sites (23.2%), but only 1,320 of 13,612 participants (9.7%).
| Segment | Trials | Sites | Participants |
|---|---|---|---|
| Small molecule | 46 | 836 | 9,913 |
| Antibody / biologic | 17 | 419 | 1,457 |
| Peptide / protein / enzyme | 19 | 329 | 1,841 |
| Pediatric / includes children | 19 | 380 | 1,320 |
| Orphan-drug flagged | 14 | 302 | 883 |
Small-molecule nephrology trials are the main enrollment engine, while pediatric and orphan-drug studies require relatively broad site networks for much smaller participant allocations.
Trials first authorized in 2024 account for 55 of 98 trials (56.1%), 999 of 1,635 site allocations (61.1%), and 10,031 of 13,612 participant allocations (73.7%). The 2025 cohort contributes 31 trials and 2,684 participants, while the 2026 cohort contributes 12 trials and 897 participants.
The strongest observed nephrology site and participant footprint sits in the 2024 authorization cohort, with later cohorts showing smaller but still active Phase II–III activity.
For nephrology Phase II–III trial planning, the most reusable EU/EEA site network is anchored by Vall d’Hebron, AP-HP, Toulouse, Charité Berlin, Strasbourg, and 12 de Octubre. Country selection should prioritize France, Spain, Italy, and Germany first, then adapt by disease cluster: glomerular/proteinuric CKD needs breadth, broad CKD needs enrollment density, and pediatric/orphan studies need specialized networks with lower participant yield.