Use of Recombinant Human Deoxyribonuclease I in Primary Ciliary Dyskinesia Bronchiectasis-A Real Life Pilot Study

Introduction: Recombinant human deoxyribonuclease I (rhDNase) cleaves DNA in mucus, facilitating increased mucociliary clearance of purulent sputum. In cystic fibrosis (CF), rhDNase improves pulmonary function and decreases exacerbations. Conversely, rhDNase use in non-CF bronchiectasis (NCFB) patients has not yielded similarly effective results. We explored the safety and feasibility of rhDNase in patients with bronchiectasis due to primary ciliary dyskinesia (PCD). Methods: In this real-life pilot study, patients with PCD received rhDNase to treat viscous mucus. We compared pulmonary function tests and pulmonary exacerbations for these patients over six months of use of rhDNase. Results: Eight PCD patients with symptomatic bronchiectasis commenced use of rhDNase at variable dosing (ranging from at least twice weekly to a full 2.5 mg dose daily). Over a six-month period, pulmonary function tests, as measured by mean FVC and FEV₁, remained relatively stable compared to prior to commencing rhDNase. Mean pulmonary exacerbations decreased from 3.1 to 2.3 in the six-month period after commencing rhDNase, as compared to the six-month period prior to rhDNase. Conclusions: Use of rhDNase in PCD patients was safe and did not adversely impact lung function or increase pulmonary exacerbations, in contrast to earlier trial results in NCFB patients with heterogeneous etiologies. Further clinical data is required to identify the population of PCD patients who can benefit from rhDNase, as well as the appropriate dosing and timing.