Aerosolized Hypertonic Xylitol Versus Hypertonic Saline in Cystic Fibrosis (CF) Subjects

Phase 1

Completed

Conditions: Cystic Fibrosis

Interventions: Drug: Hypertonic saline
Drug: Xylitol

Registration Number: NCT00928135

Lead Sponsor: Joseph Zabner

Brief Summary: Cystic fibrosis (CF) lung disease is characterized by chronic bacterial colonization and recurrent infection of the airways. Lowering the airway surface liquid (ASL) salt concentration has been shown to increase activity of salt sensitive antimicrobial peptides.

Xylitol is a 5-carbon sugar that can lower the ASL salt concentration, thus enhancing innate immunity. In this study, the investigators propose to test the safety and tolerability of aerosolized xylitol used daily for 2 weeks in subjects with cystic fibrosis. In a pilot, 2-week study, 60 subjects with cystic fibrosis with an FEV1(Forced expiratory volume in 1 second ) \>30% predicted will be randomized to receive aerosolized 7% hypertonic saline (5 ml) or 15% xylitol, (5 ml) twice a day for 14 days. The primary outcomes will be safety as assessed by FEV1 change from baseline, adverse events and respiratory symptom score. Outcomes for trend in efficacy include density of colonization of sputum, time to next exacerbation, sputum cytokines and revised CF quality of life questionnaire.

Detailed Description: Cystic fibrosis (CF) lung disease is characterized by chronic bacterial colonization and recurrent infection of the airways. Disruption of the cystic fibrosis transmembrane conductance regulator chloride channels in subjects with CF results in altered fluid and electrolyte transport across the airway epithelium thereby initiating infections.

These infections eventually destroy the lungs and contribute to significant morbidity and mortality in patients with CF. It is well known that antibacterial activity of innate immune mediators such as lysozyme and beta defensins in human airway surface liquid (ASL) is salt-sensitive; an increase in salt concentration inhibits their activity.

Conversely, their activity is increased by low ionic strength. Lowering the ASL salt concentration and increasing the ASL volume might therefore potentiate innate immunity and therefore decrease or prevent airway infections in subjects with CF.

Xylitol, a five-carbon sugar with low transepithelial permeability, which is poorly metabolized by bacteria can lower the salt concentration of both cystic fibrosis (CF) and non-CF epithelia in vitro. Xylitol is an artificial sweetener that has been successfully used in chewing gums to prevent dental caries; it has been used as an oral sugar substitute without significant adverse effects. It has also been shown to decrease the incidence of acute otitis media by 20-40%; nasal application to normal human subjects was found to decrease colonization with coagulase negative staphylococcus. We found that aerosolized iso-osmolar xylitol was safe in mice, healthy volunteers and stable subjects with CF when administered over a single day. In a recent study, we observed that single doses of 10% followed by 15% xylitol was well tolerated by subjects with cystic fibrosis who were stable. In this pilot study we propose to test the hypothesis that aerosolized hypertonic xylitol given daily for 2 weeks, will be safe and well tolerated and potentially lower the density of colonization in subjects with CF compared to hypertonic saline. We chose hypertonic concentration of xylitol to be comparable in part to hypertonic saline which is being offered as a routine treatment in hospitalized patients with CF exacerbation.

Recruitment & Eligibility

Status: COMPLETED

Sex: All

Target Recruitment: 63

Inclusion Criteria

Subjects with CF (medical record evidence of CFTR(Cystic fibrosis transmembrane conductance regulator) mutation or sweat chloride test or nasal voltage difference, and 1 or more clinical findings of CF),
Age 12 or greater
FEV1 > 30% predicted(within the last 14 days and oxygen saturation > 90% on FiO2(fraction of inspired oxygen) ≤ 50%,
Admitted for an exacerbation,
Use of effective contraception in women,
Able to provide written informed consent.

Exclusion Criteria

Pregnancy,
History of asthma based on methacholine challenge or bronchial hyperresponsiveness on PFTS(Pulmonary Function Test),
Hemoptysis more than 60 mL within the last 30 days,
Use of any investigational study drug within the last 30 days,
Initiation of hypertonic saline within the last 30 days,
A serum creatinine 2 mg/dl or more
Active malignancy in the last year
Antibiotics for CF exacerbation as an outpatient in the last 2 weeks
B cepacia colonization
Waiting list for lung transplant
Lack of FEV1 data from the last 14 days
Previous participation in this study

Study & Design

Study Type: INTERVENTIONAL

Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
7% Hypertonic saline	Hypertonic saline	5 ml of 7% saline twice daily
Hypertonic xylitol	Xylitol	5 ml of 15% xylitol twice daily

Primary Outcome Measures

Name	Time	Method
Change in FEV1 Percentage Predicted From Baseline	14 days	Change in lung function (forced expiratory volume in 1 second) between baseline and Day 14

Secondary Outcome Measures

Name	Time	Method
Exacerbations During 6 Months Follow-up	6 months	numbers of subjects that experienced an exacerbation during the 6 months follow-up
Density of Colonization of Pseudomonas Aeruginosa Per Gram of Sputum	14 days	Mean difference from baseline of Sputum density expressed as log colony forming units between baseline and Day 14