Across 52 European CTIS-authorized psoriasis and psoriatic arthritis phase 2 & 3 trials, 42 trials used CRO or CRO-tagged vendor support, equal to 80.8%. ICON/PRA was the most active support group, appearing in 13 trials, followed by IQVIA in 11 and 4G Clinical in 10. CRO need was highest once trials crossed operational scale thresholds: 100.0% of trials with 50+ sites and 100.0% of trials with 500+ participants used CRO support.
ICON/PRA led the support ecosystem with 13 of 52 trials, or 25.0% of the total cohort and 31.0% of CRO-supported trials. IQVIA followed with 11 trials, while 4G Clinical appeared in 10 trials.
The leading names are not only full-service CROs. CTIS sponsor records also tag specialist vendors for IRT, eCOA, rater training, labs, logistics, and reimbursement as CRO support, showing that outsourcing in psoriasis and psoriatic arthritis is distributed across a multi-vendor execution layer.
CRO use rises sharply with trial scale. Only 2 of 10 single-country trials used CRO support, but 19 of 19 trials with 2–5 countries and 19 of 21 trials with 6+ countries used CRO support. Every trial with 50+ sites or 500+ participants used CRO support.
| Scale driver | Bucket | CRO use | Rate |
|---|---|---|---|
| Countries | 1 country | 2 / 10 | 20.0% |
| Countries | 2–5 countries | 19 / 19 | 100.0% |
| Countries | 6+ countries | 19 / 21 | 90.5% |
| Sites | 50+ sites | 9 / 9 | 100.0% |
| Participants | 500+ participants | 6 / 6 | 100.0% |
The clearest CRO trigger is not disease alone; it is EU operating complexity. Once CTIS coordination expands beyond a single country, or once a trial becomes a 50+ site / 500+ participant program, CRO support becomes effectively standard.
Psoriatic arthritis accounted for 30 of 52 trials and had CRO support in 25 trials, equal to 83.3%. Psoriasis-only trials accounted for 19 trials, with 14 CRO-supported trials, or 73.7%. The 3 mixed psoriasis and psoriatic arthritis trials all used CRO support.
Psoriatic arthritis is the stronger outsourcing market by volume and slightly higher CRO-use rate. Its median footprint was 5.5 countries, 27 sites, and 146.5 participants, compared with psoriasis-only medians of 4 countries, 19.5 sites, and 145 participants.
The most frequently outsourced support area was laboratory, biomarker, PK/PD, and sample services, present in 40 of 52 trials. Clinical technology, eCOA/ePRO, and randomisation support followed in 32 trials.
The highest outsourcing demand is not classic site monitoring alone. The data points to an execution stack around central labs, sample handling, IRT/randomisation, eCOA/ePRO, rater training, logistics, and CTIS/EU submission administration.
The 52 trials generated 278 country-level CTIS entries across 24 European countries. CRO-supported trials accounted for 254 of those country entries, equal to 91.4%, and carried 1,283 of 1,411 sites, or 90.9%.
| Country | Country entries | Sites | Participants |
|---|---|---|---|
| Poland | 38 | 369 | 5,482 |
| Germany | 34 | 219 | 1,269 |
| Spain | 34 | 177 | 684 |
| Hungary | 23 | 116 | 731 |
| Czechia | 19 | 110 | 1,072 |
Poland is the strongest operational hotspot: 369 sites and 5,482 planned participants, equal to 26.2% of all sites and 45.9% of all planned participants. For CTIS/EU submission planning, Poland, Germany, Spain, Hungary, and Czechia should be treated as the core feasibility and site-activation corridor.
Phase 3 trials had much higher CRO use than phase 2 trials: 34 of 39 phase 3 trials used CRO support, compared with 7 of 12 phase 2 trials. Design and modality complexity also mattered: all 8 dose-escalation or multi-dose combined trials and all 3 adaptive trials used CRO support.
The best predictors of CRO need are phase 3 status, randomisation, paediatric execution, multi-dose complexity, and cross-country CTIS execution. These features create the operational burden that drives outsourcing beyond the sponsor’s internal team.
The most active CRO support organizations in European psoriasis and psoriatic arthritis phase 2 & 3 trials were ICON/PRA, IQVIA, 4G Clinical, Labcorp, PPD/Thermo Fisher, and WCG Clinical. CROs were needed most in phase 3, psoriatic arthritis, multi-country CTIS/EU submissions, 50+ site studies, and 500+ participant programs. The most outsourced functions were labs and sample services, clinical technology/eCOA/ePRO/randomisation, CTIS/EU administrative support, logistics, and data/biostatistics support.