Inhaled Dornase Alfa for Treatment of ARDS in Patients With SARS-CoV-2
Phase: PHASE3
Conditions: SARS-CoV 2, ARDS
Sponsor: University of Missouri-Columbia

Study Title: Dornase Alfa for ARDS in Patients 
with SARS-CoV-2 
 
NCT number: 04402970 
 
Document Date: Last approved/updated 
3/08/2021 

Background and Significance 
Health care systems across the world are being inundated with patients who are critically ill due to 
infection with Severe Acute Respiratory Syndrome-Coronavirus-2 (SARS-CoV-2) causing 
Coronavirus Disease 2019 (COVID-19). Around 10% of those infected will develop the most severe 
manifestation of the disease requiring admission to an intensive care unit1. Early reports suggested 
neutrophil extracellular traps (NETs) as being a potential contributor to the severity of disease in 
some patients with COVID-192. The primary innate immune role for NETs is to trap and kill invading 
microbes, but in severe cases of COVID-19, NETs appear to cause significant morbidity in the lungs 
with associated microthrombi formation, endothelial damage, capillaritis, neutrophilic mucositis and 
mucus accumulation3-6. Plasma levels of NET activity are increased in patients who requiring 
intubation and are inversely correlated with arterial blood oxygen content to fraction of inspired 
oxygen ratio (PaO2/FiO2)7. Dornase alfa, currently is in use in patients with Cystic Fibrosis, works by 
degrading large extracellular DNA in the airways8,9. We proposed a trial of using inhaled dornase alfa 
as a therapeutic target to reduce excess NETs in patients with acute respiratory distress syndrome 
(ARDS) secondary to COVID-19 pneumonia, with outcome aims including improved lung compliance 
and gas exchange10.  
 
Aims and Objectives 
Aim #1: Determine if use of nebulized dornase alfa in ARDS secondary to COVID-19 will lead to 
improved pulmonary mechanics as measured by surrogate values of PaO2/FiO2 and static lung 
compliance.  
Aim #2: Determine if use of nebulized dornase alfa in ARDS secondary to COVID-19 will lead to a 
reduction in alveolar and serum NET activity. 
 
 
 

 
Research Design 
A single center, non-randomized, controlled before-and-after clinical study was designed to examine 
the effects of inhaled dornase alfa in patients with acute respiratory distress syndrome secondary to 
COVID-19 pneumonia. A second standard of care patient population is to be collected as a case 
control group for comparison. After inclusion to the study and consent has been obtained, we will 
collect blood samples and perform diagnostic flexible bronchoscopy with bronchoalveolar lavage 
(BAL). Patients will then receive nebulized dornase alfa via vibrating mesh nebulizer through the 
ventilator circuit twice daily for 3 days. On day 4 after randomization, blood samples and BAL fluid 
samples will again be collected to determine change in serum and alveolar NET activity. Therapy will 
be discontinued in any patients who develop treatment failure defined as an increase in FiO2 by 20%, 
reduction in static lung compliance by more than 10 or need for rescue therapies such as 
extracorporeal membrane oxygenation (ECMO) or inhaled nitric oxide. Primary outcome measure will 
be change in arterial oxygen saturation to inhaled fraction of oxygen (PaO2/FiO2) before and after 
therapy. Secondary outcomes to be included will be change in static lung compliance, duration of 
mechanical ventilation, length of ICU stay, length of hospitalization, secondary bacterial infections, 
and mortality. 
Study Population and Data Collection 
Patients are to be recruited from the medical intensive care unit at the University of Missouri, a 250-
bed academic tertiary care medical center, after confirmation of ARDS secondary to SARS-CoV-2 
infection and progression of care to requiring mechanical ventilation. Inclusion criteria included age ≥ 
18 years, hospitalized, and mechanically ventilated for illness related to SARS-CoV-2 infection, with 
individual or surrogate ability to sign informed consent, and negative urine-based pregnancy test in 
female patients. Exclusion criteria included contraindication or intolerance to dornase alfa, length of 
mechanical ventilation expected to be less than 48 hours, life expectancy less than 24 hours based 
upon judgment of treatment physician, pregnancy, or inability to obtain informed consent. For the first 

5 days and at day 14 if applicable, daily measurements of PaO2/FiO2, static lung compliance, and 
positive end expiratory pressure (PEEP) will be collected. Demographic and clinical data of the 
patients to be obtained from electronic medical records at enrollment. Clinical study information will 
include age, sex, co-morbidities, therapies received, serological testing, ventilator data, bacterial and 
viral culture data, days of hospitalization, days in the intensive care unit, days of mechanical 
ventilation and mortality.  
 
Primary Statistical Plan and Analysis 
The primary hypothesis for this study is that by giving an inhaled medication targeting alveolar NET 
formation there will be an improvement in alveolar gas exchange. A control group for comparison is 
added who will have received standard of care. Improvement in alveolar gas exchange will be defined 
as a change in PF ratio from baseline for both the treatment and control groups with comparison of 
95% CI between groups. Secondary endpoints of change in static lung compliance and change in 
PEEP will be analyzed in a similar fashion to change in PF ratio. The study is not powered to 
determine additional secondary endpoints such as mortality and length of hospitalization, but values 
will be collected and analyzed as unpaired t-test with significant p-value < 0.05. Bronchoalveolar fluid 
analysis for MPO-DNA will be compared before and after therapy with paired t-test analysis with 
significant p-value < 0.05.  
 
Potential Impact 
 
Resources 
1. Emanuel EJ, Persad G, Upshur R, et al. . Fair allocation of scarce medical resources in the 
time of Covid-19. N Engl J Med. 2020;382(21):2049-2055. 
2. Earhart AP, Holliday ZM, Hofmann HV, Schrum AG. Consideration of dornase alfa for the 
treatment of severe COVID-19 acute respiratory distress syndrome. New Microbes New 
Infect. 2020;35:100689.  

3. Barnes BJ, Adrover JM, Baxter-Stoltzfus A, et al. Targeting potential drivers of COVID-19: 
Neutrophil extracellular traps. J Exp Med. 2020;217(6):e20200652. doi:10.1084/jem.20200652 
4. Schönrich G, Raftery MJ. Neutrophil extracellular traps go viral. Front Immunol. 2016;7:366. 
5. Kambas K, Chrysanthopoulou A, Vassilopoulos D, et al. Tissue factor expression in neutrophil 
extracellular traps and neutrophil derived microparticles in antineutrophil cytoplasmic antibody 
associated vasculitis may promote thromboinflammation and the thrombophilic state 
associated with the disease. Ann Rheum Dis. 2014;73(10):1854-1863. 
doi:10.1136/annrheumdis-2013-203430 
6. Brinkmann V, Reichard U, Goosmann C, et al. Neutrophil extracellular traps kill bacteria. 
Science. 2004;303(5663):1532-1535. doi:10.1126/science.1092385 
7. Middleton EA, He XY, Denorme F, et al. Neutrophil extracellular traps contribute to 
immunothrombosis in COVID-19 acute respiratory distress syndrome. Blood. 2020; 136(10): 
1169-1179. doi:10.1182/blood.2020007008 
8. Shak S, Capon DJ, Hellmiss R, Marsters SA, Baker CL. Recombinant human DNase I 
reduces the viscosity of cystic fibrosis sputum. Proc Natl Acad Sci U S A. 1990;87(23):9188-
9192. doi:10.1073/pnas.87.23.9188 
9. Ramsey BW, Astley SJ, Aitken ML, et al. Efficacy and safety of short-term administration of 
aerosolized recombinant human deoxyribonuclease in patients with cystic fibrosis. Am Rev 
Respir Dis. 1993;148(1):145-151. doi:10.1164/ajrccm/148.1.145 
10. Wang, Q., C. M. Doerschuk, and J. P. Mizgerd.  Neutrophils in innate immunity. Semin Respir  
Crit. Care Med. 2004. 25:33-41.