Disrupted Vessels-Connected Voices: Why Patient Partnership and Cross-Disease Collaboration Are Essential for Accelerating HHT Research.

Rare vascular diseases such as hereditary haemorrhagic telangiectasia (HHT) represent a big challenge in biomedicine: complex pathomechanisms, limited patient material, and fragmented research communities slow down therapeutic progress. We argue that two elements are pivotal to bypass this problem. First, genuine partnership with patients-ranging from biospecimen donation to agenda setting-can unlock critical resources and align research with real-world needs. Second, molecular intersections between HHT and related pathologies call for coordinated, cross-disease programmes rather than isolated efforts. Recent multi-stakeholder gatherings hosted by patient organisations in Germany and elsewhere, such as the Second Scientific Symposium by the German HHT self-help group (Morbus Osler Selbsthilfe e.V.) in May 2025, have shown that when clinicians, basic scientists from different disciplines, and affected families co-design research questions, novel in vitro models can be generated more accurately, and pragmatic clinical trials emerge. Here, we outline actual opportunities for patient-integrated cellular model systems, shared biobanking, and comparative approaches across vascular malformation syndromes. In our opinion, letting informed and well-organised patient communities assemble such meetings opens unique opportunities twofold: on the one hand, the field can finally break out of its disease-specific silos; on the other hand, the development of novel HHT therapies could be accelerated by learning from progress in related pathologies.