Across 78 unique CTIS head and neck cancer / HNSCC trials authorized from 2024–2026, the European site network is concentrated in a small set of oncology hubs. Institut Gustave Roussy leads with 30 trial participations, followed by Hospital Universitari Vall d’Hebron with 28. France is the largest country market with 379/1,447 site slots (26.2%) and 3,542/10,345 planned participants (34.2%).
The top 10 sites account for repeated participation across 78 unique trials. Institut Gustave Roussy appears in 30/78 trials (38.5%), while Hospital Universitari Vall d’Hebron appears in 28/78 trials (35.9%).
For sponsor feasibility, the practical first screen is not country alone. A small number of high-repetition HNSCC hubs—especially Gustave Roussy and Vall d’Hebron—anchor access to both early-phase and pivotal oncology infrastructure.
Country-level site allocation is led by France with 379/1,447 site slots (26.2%), followed by Spain with 295/1,447 (20.4%), Germany with 185/1,447 (12.8%), and Italy with 175/1,447 (12.1%).
France is the clearest anchor market because it combines the highest site count and the highest planned patient allocation. Spain is the second operational pillar, while Germany and Italy add broad site coverage but lower patient concentration than France.
Phase III accounts for 23/78 trials (29.5%), but 611/1,447 site slots (42.2%) and 5,047/10,345 planned participants (48.8%).
Early-phase HNSCC work is important for site selection, but the heavy operational footprint comes from pivotal and phase-bridging programs. This suggests that late-phase country feasibility should be pressure-tested separately from early-phase investigator access.
Recurrent/metastatic HNSCC represents 18/78 trials (23.1%) but 661/1,447 site slots (45.7%), making it the largest operational segment.
The site burden is not evenly distributed across head and neck cancer. Recurrent/metastatic programs require the widest operational network, while multi-tumor baskets include many trials but generate fewer site slots per trial.
Monoclonal antibodies appear in 46/78 trials (59.0%), followed by small molecules in 33/78 (42.3%) and antibody-drug conjugates (ADCs) in 9/78 (11.5%). Combination treatment is used in 49/78 trials (62.8%).
The HNSCC site network is still shaped primarily by immuno-oncology and chemo-immunotherapy infrastructure. ADCs are visible but remain a smaller segment, concentrated in early and phase-bridging development rather than dominating the overall site map.
HNSCC means head and neck squamous cell carcinoma. A site participation means one site appearing in one unique trial. A country-level site slot is the site count allocated to a country within a trial. Trial-level modality counts allow one trial to contribute to multiple modalities when the protocol includes combination products.