Clinical Trial Intelligence

Which EU sites are most active in depression and major depressive disorder Phase II–III trials?

7 June 2026

Across 49 CTIS depression/MDD Phase II–III trial records from 2024–2026, the dataset contains 600 site allocations and 7,193 planned participants. Phase III is the dominant operational segment, accounting for 486 of 600 site allocations and 5,354 of 7,193 participants, while Phase II contributes a smaller but more geographically varied early-development footprint.

Trial records
49
Site allocations
600
Planned participants
7,193
Phase III participant share
74.4%

Phase III dominates the MDD execution footprint

Phase III records account for 33 of 49 trials, 486 of 600 site allocations, and 5,354 of 7,193 planned participants. Phase II contributes 16 of 49 records, 114 site allocations, and 1,839 planned participants.

Participant allocation by phase
Phase III74.4%
Phase II25.6%
Share of 7,193 planned participants
Interpretation

For sponsors planning depression/MDD execution, competitive pressure is highest in late-stage site networks: Phase III absorbs more than three quarters of the participant burden and over four fifths of site allocations.

Which site networks appear most often?

The most recurrent site listings are concentrated in Central and Eastern Europe, with Bulgaria, Poland, Czechia, Slovakia, and Hungary supplying several repeat psychiatric research sites. The leading visible site was Medical Center Hera EOOD, appearing 8 times across Phase II–III site listings.

Top visible EU site listings
Rank Site Country Listings
1Medical Center Hera EOODBulgaria8
2Mental Health Center Sofia EOODBulgaria5
3Clintrial s.r.o.Czechia4
4Medical Center Intermedica Ltd.Bulgaria4
5PsychoLine s.r.o.Slovakia4
6Crystal Comfort s.r.o.Slovakia4
7Semmelweis UniversityHungary3
8Clinexpert Kft.Hungary3
9Processus Kft.Hungary3
10Hospital Clinic de BarcelonaSpain3
Ranking based on visible site-list appearances across Phase II–III geography records
Interpretation

The most repeatable operational footprint is not only in academic hospitals. Dedicated psychiatric clinics and private research centers appear repeatedly, which suggests that depression/MDD recruitment depends heavily on specialized outpatient networks.

Phase II country allocation is broad but uneven

In Phase II, 13 countries account for 114 site allocations and 1,839 planned participants. Norway leads by planned participants with 230 of 1,839, followed by Denmark with 220, Sweden with 214, Poland with 211, and Czechia with 188.

Top Phase II countries by planned participants
Norway12.5%
Denmark12.0%
Sweden11.6%
Poland11.5%
Czechia10.2%
Percent of 1,839 Phase II planned participants
Interpretation

Phase II depression/MDD development is not concentrated in one dominant country. The top five countries account for 1,063 of 1,839 planned participants, or 57.8%, suggesting that early-stage recruitment is distributed across multiple Nordic, Central European, and Eastern European networks.

Which disease subtypes are driving site activity?

Major depressive disorder is the dominant label in the cohort, with related depression subtypes including treatment-resistant depression, bipolar depression, chronic depression, postpartum/perinatal depression, and seasonal affective disorder. Phase II contains 16 trial records, including 8 records explicitly using major depressive disorder and 5 records including treatment-resistant depression.

Visible Phase II disease labels
8
MDD-labelled records
5
TRD-labelled records
2
General depression records
1
Postpartum/perinatal record
Labels are counted from Phase II trial disease strings; records can include more than one label
Interpretation

The operational opportunity is broad depression, but the highest-value recruitment capability is likely in MDD and treatment-resistant depression, where protocol volume and site reuse are strongest.

Definitions

MDD means major depressive disorder. TRD means treatment-resistant depression. Site allocations count country-level site entries as reported in CTIS geography records; planned participants are summed from country-level or trial-level planned participant fields.