Pilot study to test inhaled nitric oxide in cystic fibrosis patients with refractory Mycobacterium abscessus lung infection

• Published in: Journal of cystic fibrosis Vol. 19; no. 2; pp. 225 - 231
• Main Authors: Bentur, Lea, Gur, Michal, Ashkenazi, Moshe, Livnat-Levanon, Galit, Mizrahi, Marko, Tal, Asher, Ghaffari, Abdi, Geffen, Yuval, Aviram, Micha, Efrati, Ori
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.03.2020
• Subjects: Cystic fibrosis; Inhaled nitric oxide; Mycobacterium Abscessus; Pulmonary/Respiratory; CRP; M. abscessus; NTM; GSNO; AEs; NO2; SD; CFU; Inhaled nitric oxide; qPCR; Mycobacterium Abscessus; ARDS; CF; MABSC; SpO2; Cystic fibrosis; iNO; 6MWT; FVC; NOS; SNOs; FEV1; MetHb; SAEs; 6MWD; CFTR; C-Reactive Protein; Colony Forming Unit; Standard Deviation; Forced Expiratory Volume in 1 s; Six-Minute Walk Test; Acute Respiratory Distress Syndrome; Cystic Fibrosis Transmembrane Conductance Regulator; Nitrogen Dioxide; Non-Tuberculosis Mycobacteria; Adverse Events; Forced Vital Capacity; Six-Minute Walk Distance; Methemoglobin; Quantitative Polymerase Chain Reaction; Mycobacterium Abscessus Complex; Nitric Oxide Synthase; Serious Adverse Events; S-nitrosothiols; S-nitrosoglutathione; Mean Peripheral Oxygen saturation
• ISSN: 1569-1993; 1873-5010; 1873-5010
• DOI: 10.1016/j.jcf.2019.05.002

Airways of Cystic Fibrosis (CF) patients are Nitric Oxide (NO) deficient which may contribute to impaired lung function and infection clearance. Mycobacterium abscessus (M. abscessus) infection prevalence is increasing in CF patients and is associated with increased morbidity and mortality. Here, we assess the safety and efficacy of intermittent inhaled NO (iNO) as adjuvant therapy in CF patients with refractory M. abscessus lung infection. A prospective, open-label pilot study of iNO (160 ppm) administered five times/day during hospitalization (14 days), and three times/day during ambulatory treatment (7 days) was conducted. The primary outcome was safety measured by NO-related adverse events (AEs). Secondary outcomes were six-minute walk distance (6MWD), forced expiratory volume in 1 s (FEV1), and M. abscessus burden in airways. Nine subjects were recruited. INO at 160 ppm was well-tolerated and no iNO-related SAEs were observed during the study. Mean FEV1 and 6WMD were increased relative to baseline during NO treatment. M. abscessus culture conversion was not achieved, but 3/9 patients experienced at least one negative culture during the study. Mean time to positivity in M. abscessus culture, and qPCR analysis showed reductions in sputum bacterial load. The study was not powered to achieve statistical significance in FEV1, 6WMD, and bacterial load. Intermittent iNO at 160 ppm is well tolerated and safe and led to increases in mean 6MWD and FEV1. INO exhibited potential antibacterial activity against M. abscessus. Further evaluation of secondary endpoints in a larger cohort of CF patients is warranted to demonstrate statistical significance. •Intermittent 160ppm inhaled NO is safe and tolerable in NTM-CF patients.•Intermittent high-dose iNO therapy may improve lung function in NTM-CF patients.•High-dose iNO may reduce M. abscessus bacterial burden in airways.