Clinical Trial Intelligence

Which EU/EEA Sites Lead ADC Phase II/III Trial Participation?

15 June 2026

Across 285 antibody-drug conjugate (ADC) Phase II/III trials, the strongest site signal is Spanish: Hospital Universitari Vall d’Hebron appears in 119 trials, equal to 41.8% of the dataset. Spain also leads country-level activity with 8,773 planned participant allocations (20.8%) and 1,786 planned site allocations (21.3%).

Trials included
285
Top site
Vall d’Hebron
119 trial appearances
Planned site allocations
8,375
Planned participants
42,231

Which named sites appear most often in ADC Phase II/III trials?

The top 10 named sites account for 757 of 8,285 named site-trial appearances (9.1%). Five of the top 10 are in Spain, three are in Italy, and two are in France.

Top 10 named EU/EEA sites
01
Hospital Universitari Vall D Hebron
Spain · 41.8% of 285 trials
119
02
Institut Gustave Roussy
France · 29.5% of 285 trials
84
03
Institut Catala D'oncologia
Spain · 29.1% of 285 trials
83
04
Hospital Clinic De Barcelona
Spain · 27.4% of 285 trials
78
05
Hospital Universitario 12 De Octubre
Spain · 27.0% of 285 trials
77
06
Fondazione Policlinico Universitario Agostino Gemelli IRCCS
Italy · 25.6% of 285 trials
73
07
Fondazione IRCCS Istituto Nazionale Dei Tumori
Italy · 23.9% of 285 trials
68
08
Centre Leon Berard
France · 21.8% of 285 trials
62
09
Istituto Europeo Di Oncologia S.r.l.
Italy · 20.0% of 285 trials
57
10
Hospital Universitario Ramon Y Cajal
Spain · 19.6% of 285 trials
56
Site appearance = one named site appearing in one ADC Phase II/III trial geography record.
Interpretation

ADC trial access is concentrated in high-volume comprehensive oncology centers. Vall d’Hebron, Gustave Roussy, Catalan Oncology Institute, Hospital Clínic de Barcelona, and 12 de Octubre form the clearest Iberian/French hub pattern.

Which countries carry the largest ADC participant and site allocations?

Spain, France, Germany, and Italy together account for 30,172 of 42,231 planned participant allocations (71.4%) and 5,827 of 8,375 planned site allocations (69.6%).

Top 10 countries by planned participants
Spain
1,786 planned site allocations · 201 trials
20.8%
8,773
France
1,422 planned site allocations · 162 trials
18.5%
7,803
Germany
1,368 planned site allocations · 149 trials
18.3%
7,745
Italy
1,251 planned site allocations · 167 trials
13.9%
5,851
Poland
519 planned site allocations · 99 trials
7.5%
3,165
Belgium
402 planned site allocations · 100 trials
4.5%
1,910
Netherlands
227 planned site allocations · 63 trials
2.8%
1,203
Greece
210 planned site allocations · 57 trials
2.3%
982
Czechia
191 planned site allocations · 49 trials
1.9%
809
Hungary
188 planned site allocations · 43 trials
1.5%
642
Country-level planned participant allocations across ADC Phase II/III trials.
Interpretation

The leading ADC geography is not evenly distributed. Spain leads both site and participant allocations, while France and Germany are nearly tied on planned participants despite France having fewer planned site allocations than Spain.

Which disease areas drive ADC site demand?

Breast cancer is the largest ADC site-demand category, with 2,236 of 8,375 planned site allocations (26.7%) and 16,042 of 42,231 planned participant allocations (38.0%). Breast, lung, hematologic, and gynecologic indications together represent 77.4% of all planned site allocations.

Disease families by planned site allocation share
Breast cancer
64 trials · 16,042 planned participants
26.7%
Lung cancer
59 trials · 6,868 planned participants
22.2%
Hematologic malignancy
54 trials · 6,771 planned participants
14.6%
Gynecologic cancer
23 trials · 4,663 planned participants
13.9%
Gastrointestinal cancer
28 trials · 2,062 planned participants
9.4%
Urothelial / bladder cancer
18 trials · 2,253 planned participants
8.5%
Basket / advanced solid tumors
12 trials · 1,713 planned participants
2.4%
Other oncology
9 trials · 756 planned participants
1.2%
Disease family grouping based on trial disease labels in the ADC cohort.
Interpretation

ADC development is still dominated by oncology scale indications. Breast and lung cancer alone account for 48.9% of planned site allocations, while hematologic and gynecologic indications add a second major operating layer.

Where are the main disease-specific ADC site clusters?

Across the six largest disease families and six largest countries, Spain has the highest site allocation in breast cancer (495), lung cancer (450), and urothelial/bladder cancer (177). Germany leads hematologic malignancy allocations (246), while Italy leads gastrointestinal cancer allocations (178).

Planned site allocations by disease family and country
SpainFranceGermanyItalyPolandBelgium
Breast cancer
495
403
485
283
108
112
Lung cancer
450
276
244
277
149
83
Hematologic malignancy
197
212
246
190
88
38
Gynecologic cancer
187
193
139
165
81
82
Gastrointestinal cancer
150
126
124
178
40
45
Urothelial / bladder cancer
177
130
98
102
28
24
Cell values show planned site allocations, not enrolled participants.
Interpretation

The country mix changes by indication. Spain is the broadest ADC hub across solid tumors, Germany is comparatively strong in hematologic malignancies, and Italy over-indexes in gastrointestinal cancer site allocation.

How much of the ADC site footprint is late-stage?

Phase III ADC trials account for 4,995 of 8,375 planned site allocations (59.6%) and 24,155 of 42,231 planned participant allocations (57.2%). By authorization year, 2024 contributes 4,258 planned site allocations (50.8%).

Phase and authorization-year distribution
Phase III
59.6%
4,995 planned site allocations
Phase II
40.4%
3,380 planned site allocations
2024: 4,258 sites 2025: 3,116 sites 2026: 1,001 sites
Phase II and Phase III ADC trials, 2024–2026 authorization years.
Interpretation

Although the cohort includes more Phase II than Phase III trials, the operational load is later-stage: Phase III contributes nearly six in ten planned site allocations and planned participant allocations.

Definitions

ADC means antibody-drug conjugate.

Site allocation means a planned trial site counted at the country level in the trial geography record.

Site appearance means one named site appearing in one ADC trial. A site appearing in multiple trials is counted once per trial for ranking purposes.