PT - JOURNAL ARTICLE AU - Michael D Davis AU - Brian K Walsh AU - Scott T Dwyer AU - Casey Combs AU - Nico Vehse AU - Alix Paget-Brown AU - Thomas Pajewski AU - John F Hunt TI - Safety of an Alkalinizing Buffer Designed for Inhaled Medications in Humans AID - 10.4187/respcare.01753 DP - 2013 Jul 01 TA - Respiratory Care PG - 1226--1232 VI - 58 IP - 7 4099 - http://rc.rcjournal.com/content/58/7/1226.short 4100 - http://rc.rcjournal.com/content/58/7/1226.full AB - BACKGROUND: Airway acidification plays a role in disorders of the pulmonary tract. We hypothesized that the inhalation of alkalinized glycine buffer would measurably alkalinize the airways without compromising lung function or causing adverse events. We evaluated the safety of an inhaled alkaline glycine buffer in both healthy subjects and in subjects with stable obstructive airway disease.METHODS: This work includes 2 open-label safety studies. The healthy controls were part of a phase 1 safety study of multiple inhalations of low-dose alkaline glycine buffer; nebulized saline was used as a comparator in 8 of the healthy controls. Subsequently, a phase 2 study in subjects with stable obstructive airway disease was completed using a single nebulized higher-dose strategy of the alkaline inhalation. We studied 20 non-smoking adults (10 healthy controls and 10 subjects with obstructive airway disease), both at baseline and after inhalation of alkaline buffer. We used spirometry and vital signs as markers of clinical safety. We used changes in fraction of exhaled nitric oxide (NO) and exhaled breath condensate (EBC) pH as surrogate markers of airway pH modification.RESULTS: Alkaline glycine inhalation was tolerated by all subjects in both studies, with no adverse effects on spirometric parameters or vital signs. Airway alkalinization was confirmed by a median increase in EBC pH of 0.235 pH units (IQR 0.56–0.03, P = .03) in subjects after inhalation of the higher-dose alkaline buffer (2.5 mL of 120 mmol/L glycine).CONCLUSIONS: Alkalinization of airway lining fluid is accomplished with inhalation of alkaline glycine buffer and causes no adverse effects on pulmonary function or vital signs.