Longitudinal Characterization of Respiratory Tract Exacerbations and Treatment Responses in Primary Ciliary Dyskinesia

This is a longitudinal, prospective multicenter study to characterize acute respiratory illnesses (ARIs) and response to treatment in PCD patients. Participants (N=125) will be children age ≥6 years and adults with definite PCD. Participants will be enrolled for approximately 13 months, during which they will attend at least two study visits and perform home monitoring. Participants will be encouraged to attend study visits in-person but will have the option for virtual telehealth visits to ensure compliance with local guidelines and participant safety. Endpoints will be assessed during both well state (i.e., patients typical state of health) and sick state (i.e., during each self-reported period of acute respiratory illness). Informed consent will be obtained, after which the participant will be receive a home spirometer and instructed in its use This design allows for a training period in order to become proficient with home spirometry, with the first study visit occurring 1 month ± 2 weeks after enrollment and the second 12 (±1) months after visit 1 (coordinated with routine clinic visits as possible). Participants will also participate in a set of two optional ARI visits during one ARI, scheduled between 3-5 business days of study team notification by the participant of the new ARI and 2-4 weeks later.

Inclusion criteria

• Diagnosis of PCD

• Clinical features consistent with PCD PLUS
• At least 1 diagnostic test consistent with PCD:

i) Biallelic pathogenic variants in PCD-associated genes identified by genetic panel testing including deletion/duplication analysis; ii) Ciliary ultrastructural defect by transmission electron microscopy known to be disease-causing, including outer dynein arm defects, outer dynein arm plus inner dynein arm (IDA) defects, IDA defects with microtubular disorganization and absent central pair

• Age ≥ 6 years
• At least one course of antibiotics (oral or IV) in the prior year prescribed to treat new or increased respiratory symptoms
• Smart phone and/or internet access available in home
• Informed consent provided by participant or parent/guardian, with assent provided as applicable

Exclusion criteria

• Acute course of antibiotics for respiratory symptoms completed <14 days prior to enrollment or Visit 1 (evaluated at enrollment and Visit 1; visit may be rescheduled >14 days after completion of antibiotics)
• Developmental or cognitive disability that would impair ability to complete PRO instruments or perform spirometry
• Congenital heart disease OTHER THAN repaired or resolved atrial septal defect (ASD) or ventricular septal defect (VSD)
• Asplenia or functional asplenia
• Co-existing non-pulmonary disease that, in the opinion of the investigator, could have significant impact on lung function or health-related quality of life (e.g., severe scoliosis) or overall health status (e.g., cancer, severe renal disease)
• Listed for or post-lung transplantation