Study of Inhaled RCT1100 in Adults With PCD Caused by Pathogenic Mutations in the DNAI1 Gene to Measure Mucociliary Clearance

Major Inclusion Criteria: * The participant is a male or female, 18 to 75 years of age, inclusive, at the time of consent. * Participant has disease-causing (pathogenic and/or likely pathogenic) mutations in the DNAI1 gene. * The participant has a percent predicted forced expiratory volume in 1 second (FEV1pp) of at least 40% predicted. Exclusion Criteria: * History or presence of clinically significant medical, surgical, clinical laboratory, or psychiatric condition or disease. * History of cancer, with exception of adequately treated basal cell or squamous cell carcinoma of the skin. * Predisposition to bleeding or clinically meaningful hemorrhagic event in the 12 months prior * Medically significant hemoptysis. * Anticoagulation therapy for the treatment of a pulmonary embolus or has had a pulmonary embolus in the last 6 months of screening. * Active tuberculosis infection. * 12-lead ECG with QT interval \>450 msec (or \>480 msec for BBB) * Laboratory abnormalities in clinical laboratory tests at screening: 1. Serum creatinine level 2. Total bilirubin, aspartate aminotransferase or alanine aminotransferase values 3. Hematological or coagulation values outside the normal reference range * Any medical history of disease that has the potential to cause a rise in total bilirubin over the ULN. * COVID-19 infection within 4 weeks of Screening or receipt of COVID-19 vaccine within 2 weeks prior to first dose of RCT1100. * Receipt of vaccine with live virus, attenuated live virus, or live viral components within 2 weeks prior to first dose of RCT1100 or to receive these vaccines during treatment or within 8 weeks of completion of study treatment. Other protocol defined inclusion/exclusion criteria may apply.