Primary ciliary dyskinesia (PCD) is a rare genetic disorder characterised by impaired mucociliary clearance leading to irreversible lung damage. In contrast to other rare lung diseases like cystic fibrosis (CF), there are only few clinical trials and limited evidence-based treatments. Management is mainly based on expert opinions and treatment is challenging due to a wide range of clinical manifestations and disease severity. To improve clinical and translational research and facilitate development of new treatments, the clinical trial network for PCD (PCD-CTN) was founded in 2020 under the framework of the European Reference Network (ERN)-LUNG PCD Core. Applications from European PCD sites interested in participating in the PCD-CTN were requested. Inclusion criteria consisted of patient numbers, membership of ERN-LUNG PCD Core, use of associated standards of care, experience in PCD and/or CF clinical research, resources to run clinical trials, good clinical practice (GCP) certifications and institutional support. So far, applications from 22 trial sites in 18 European countries have been approved, including >1400 adult and >1600 paediatric individuals with PCD. The PCD-CTN is headed by a coordinating centre and consists of a steering and executive committee, a data safety monitoring board and committees for protocol review, training and standardisation. A strong association with patient organisations and industrial companies are further cornerstones. All participating trial sites agreed on a code of conduct. As CTNs from other diseases have demonstrated successfully, this newly formed PCD-CTN operates to establish evidence-based treatments for this orphan disease and to bring new personalised treatment approaches to patients.

Association des Patients Ayant une Dyskinésie Ciliaire Primitive Saint Etienne France

Berlin Institute of Health at the Charité Universitätsmedizin Berlin Corporate Member of Freie Universität Berlin Humboldt Universität zu Berlin Berlin Germany

Danish Primary Ciliary Dyskinesia Centre Paediatric Pulmonary Service Dept of Paediatrics and Adolescent Medicine Copenhagen University Hospital Rigshospitalet Copenhagen Denmark

Dept of General Pediatrics University Hospital Muenster Muenster Germany

Dept of Paediatric Pulmonology University Children's Hospital of Ruhr University Bochum at St Josef Hospital Bochum Germany

Dept of Paediatrics 2nd Faculty of Medicine Charles University and Motol University Hospital Prague Czech Republic

Dept of Pediatric Pulmonology Emma Children's Hospital Amsterdam UMC Location VUmc Amsterdam the Netherlands

Dept of Pediatric Pulmonology Hacettepe University Faculty of Medicine Ankara Turkey

Dept of Pediatric Pulmonology Hospital Universitari Vall d'Hebron VHIR Vall d'Hebron Barcelona Hospital Campus Barcelona Spain

Dept of Pediatric Respiratory Medicine Immunology and Critical Care Medicine Charité Universitätsmedizin Berlin Corporate Member of Freie Universität Berlin and Humboldt Universität zu Berlin Berlin Germany

Dept of Pediatrics University Hospital Leuven Leuven Belgium

Dept of Pulmonology Amsterdam UMC Location AMC Amsterdam the Netherlands

Dept of Respiratory Medicine Amsterdam UMC University of Amsterdam Amsterdam the Netherlands

Dept of Respiratory Medicine Hannover Medical School and DZL Hannover Germany

Dept of Respiratory Medicine University Hospitals of Leicester Leicester UK

Division of Pediatric Pulmonology Allergology and Endocrinology Dept of Pediatrics and Adolescent Medicine Medical University of Vienna Vienna Austria

Division of Pediatric Pulmonology Pendik Training and Research Hospital Marmara University Istanbul Turkey

ENT Dept La Fe Polytechnic and University Hospital and Surgery Dept University of Valencia CIBER of Rare Diseases Carlos 3 Health Institute Ministry of Science and Innovation Valencia Spain

German Center for Lung Research Berlin Germany

Kartagener Syndrom and Primäre Ciliäre Dyskinesie e V Hannover Germany

Medical School University of Cyprus Nicosia Cyprus

Paediatric Pulmonology Unit Hospital Clínico Universitario Valencia Valencia Spain

PCD Centre and Dept of Paediatric Respiratory Medicine Royal Brompton Hospital and NHLI Imperial College London UK

PCD Diagnosis and Research Dept of Respiratory Sciences University of Leicester Leicester UK

PCD Support UK Buckingham UK

Pediatric Pulmonology and Respiratory Intermediate Care Unit Sleep and Long Term Ventilation Unit Academic Department of Pediatrics Bambino Gesù Children's Hospital IRCCS Rome Italy

Pediatric Pulmonology Dept of Translational Medical Sciences Federico 2 University Azienda Ospedaliera Universitaria Federico 2 Naples Italy

Pediatric Pulmonology Dept Reference Center for Rare Lung Diseases Armand Trousseau Hospital AP HP Paris France

Pneumology Dept Hospital Universitari Vall d'Hebron Vall d'Hebron Institut de Recerca Vall d'Hebron Barcelona Hospital Campus Barcelona Spain

Primary Ciliary Dyskinesia Centre NIHR Biomedical Research Centre University Hospital Southampton NHS Foundation Trust Southampton UK

Primary Ciliary Dyskinesia Management Centre Leeds Teaching Hospitals NHS Trust Leeds UK

Pulmonology and Allergology Section Unit of Pediatrics Pisa University Hospital Pisa Italy

Service d'ORL Hôpital Henri Mondor et Centre Hospitalier Intercommunal de Créteil AP HP Créteil France

Service de Pneumologie Hôpital Henri Mondor et Centre Hospitalier Intercommunal de Créteil Assistance Publique Hôpitaux de Paris Créteil France

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