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(funded by Cystic Fibrosis Foundation Therapeutics, Inc. (CFFT))

Cystic fibrosis (CF) is a genetic disorder caused by mutations in the gene encoding the cystic fibrosis transmembrane conductance regulator (CFTR) protein. Over 1,900 mutations, categorized into five genotypic or functional classes are implicated in causing
CF. Severity of disease varies widely in CF based on CFTR-dependent and independent factors. Progressive obstructive lung disease is the main determinant of morbidity and mortality in CF; therefore it is critical to identify biomarker profiles that reflect and predict
this phenotypic variability, and understand their relationship to residual CFTR activity. Emerging CFTR modulator therapies that directly target defective CFTR are being evaluated in pivotal clinical trials and may become available in the next few years. It is not known how partial restoration of CFTR function might impact CF disease progression and disease-related biomarkers. Thus there is urgent need to i) identify and validate biomarkers that might reflect partial restoration of CFTR function and can be used to monitor disease
progression, and ii) evaluate the mechanistic effects of CFTR modulators on biomarkers and exploratory outcome measures in individuals with CF.
This is a two-part, multi-center, prospective longitudinal, exploratory study of biomarkers, clinical and physiological profiles in CF.



(funded by Department of Defense (DoD))

Deployment of military personnel has been associated with increased respiratory morbidity likely due, in part, to inhalation of novel particulate matter (PM), such as from burn pits. Inflammation is a key initial response to inhaled particulates. Our center has developed a protocol using inhaled wood smoke particles (WSP) as a model agent to study PM-induced airway inflammation. Prednisone is a well-known anti-inflammatory agent used in the treatment of airway inflammatory diseases, such as asthma. Efficacy of prednisone has not been studied in the context of PM-induced airway inflammation, such as that seen in military personnel. We hypothesize that a single dose of oral prednisone will reduce neutrophilic airway inflammation following WSP exposure.

Healthy adults demonstrating a >10% increase in sputum %PMNs following WSP exposure in a separate screening protocol will be invited back to participate in this randomized, double-blind, placebo-controlled cross-over study.

In-vivo effects of E-cigarette aerosol on innate lung host defense

(funded by National Institute of Health (NIH))

While e-cigs are commonly represented as safer alternatives to tobacco cigarettes, little is known regarding the health effects of their short- or long-term use. The responses and the e-cig components exerting these effects on the airways are largely unknown. Hence, a critical need currently exists in identifying e-cig components, namely specific flavors, modifying respiratory immune responses.


Phase I Assessment of Hypertonic Saline in Moderate to Severe Asthmatics

( funded by NIH National Heart, Lung, and Blood Institute (NHLBI)

Mucus in the respiratory tract is an important part of asthma and can cause asthma symptoms to be severe. Currently there are no medications that specifically target mucus in patients with asthma. Hypertonic saline (HS) is concentrated salt water, also known as 7% sodium chloride solution. In patients with other lung diseases like cystic fibrosis, which involves large amounts of mucus blocking the airways, inhaling HS helps to loosen the mucus and improve movement of mucus out of the lungs. In studies done at our center, HS has been used to help people cough up samples of mucus-containing material called sputum. HS has been well tolerated by people with mild asthma. The purpose of this study is to see if HS improves movement of mucus out of the lungs in people with asthma that is more severe.


Effect of gamma tocopherol enriched supplementation on response to inhaled O3 exposure

(funded by National Institute of Environmental Health Sciences (NIEHS))

The purpose of this study was to assess whether a gamma tocopherol supplement decreases O3-induced responses in mild allergic asthmatics. To study the effects of 1200mg gamma tocopherol (yT), a form of vitamin E, given daily on the response of the airway in mild asthmatics after exposure to ozone (O3)

This study is considered a randomized, double blind  and cross-over study.

Effect of gamma tocopherol enriched supplementation on response to inhaled LPS

(funded by National Institute of Environmental Health Sciences (NIEHS))

Asthma is the most commonly encountered breathing disease in children and adults in the United States and is a leading cause of illness worldwide. Endotoxin is part of outdoor air pollution and is found in a number of different workplaces.  It is even found in homes, and it is in cigarette smoke.  Endotoxin is believed to be one of the triggers for asthma attacks.

The purpose of this study is to see if giving people the vitamin E taken in a capsule will affect the lung response to the inhaled endotoxin.  This study is considered a cross-over study,

Standardization of Mucociliary Clearance (MCC) Methodology

(funded by CF Foundation)

Mucociliary and cough clearance (MCC and CC), innate host defense mechanisms important for keeping the airways cleansed of bacteria and viruses are impaired in cystic fibrosis (CF). The ability to accurately measure MCC and CC in CF patients is critical to assessment of new therapies designed to improve their function, and, as a result, decrease pulmonary exacerbations and decline in lung function (link to pdf download Donaldson et al, Proc Am Thorac Soc 4:399–405, 2007). A few CF centers have shown the capability to make measurements of MCC/CC but the techniques across these centers are not standardized, making comparison of results difficult at times. With the increasing development of new mucoactive drugs designed to improve MCC/CC in CF it is vital to develop standard techniques for these measures so that full advantage may be taken of limited CF patient populations available for such studies (link to pdf download Bennett et al J Aerosol Med Pulm Drug Deliv. 2010; 23(5):261-72). Additionally, these new, standardized methods may be used to assess impairment of MCC/CC in individuals with a smoking history that may lead to chronic obstructive lung disease.

The technique for measuring MCC/CC involves patient inhalation of radiolabeled particles followed by scanning with a gamma camera to determine the rate of particle movement from the lungs. It is vital, however, to develop standard techniques for these measures that can eventually be transferred to other CF centers to make larger CF patient populations available for such studies. Using standardized methods, we recently found that MCC and MCC/CC were similar in healthy adult subjects studied at three different CF centers (Johns Hopkins U and U of Pittsburgh). This standardized protocol may prove beneficial in multi-center trials for testing new therapies that are designed to improve MCC/CC (link to pdf download Bennett et al J Aerosol Med Pulm Drug Deliv. 2013; 26(3):157-64).

Hypertonic Saline in Cystic Fibrosis

Durability of Hypertonic Saline for Enhancing Mucociliary Clearance in Cystic Fibrosis (funded by Novartis Pharmaceuticals)

Direct measurement of mucociliary and cough clearance (MCC/CC) has been used as a biomarker in cystic fibrosis, and additional knowledge of the performance of this biomarker can further exploratory clinical trial designs, enabling support of programs to develop new inhaled therapies (link to pdf download Donaldson et al, Proc Am Thorac Soc 4:399–405, 2007).

There is a reduction in epithelial lining fluid height in cystic fibrosis as a consequence of decreased function of the Cystic Fibrosis Transmembrane conductance Regulator (CFTR) chloride channel and related increased activity of the Epithelial Sodium Channel that results in impaired mucociliary clearance (MCC), mucus stasis, inflammation, infection, and ultimately progressive bronchiectasis. Inhalation of hypertonic saline, through a direct osmotic effect on the airways, results in an increase in epithelial lining fluid height in vitro and increase in MCC in vivo as measured following inhalation of a radiotracer with gamma scintigraphy (link to pdf download Donaldson et al, N Eng J Med 354:241-50, 2006).

Blockade of the Epithelial Sodium Channel for a period of at least 4 hours may be required to achieve the necessary durability to achieve clinical success in improving lung function in CF patients. This durability should also enable twice daily dosing. For comparison we need to know the effectiveness of hypertonic saline over the same period.

The purpose of the Novartis clinical study was 1) To determine the durability of improvement in mucociliary and cough clearance (MCC/CC) following inhalation of single doses of inhaled hypertonic saline (7%) on cystic fibrosis (CF) patients, 2) To determine the inter-individual variability of baseline MCC/CC measurements in adult CF patients, 3) To determine the inter-individual variability of MCC/CC measurements following inhalation of hypertonic saline in CF patients, and compare similar measurements of MCC/CC made at John Hopkins University.

Surfactant in CF

A Double Blind, Cross-over Study Comparing Aerosolized Lucinactant and Vehicle on Mucociliary Clearance for Cystic Fibrosis Lung Disease (funded by the CF Foundation)

In cystic fibrosis (CF), dysregulated ion transport leads to depletion of the airway surface liquid (ASL) layer and the subsequent formation of mucus plaques that adhere to airway surfaces. As a result, cilia and cough-dependent clearance slows in affected lung regions, airways become obstructed and chronic infection and inflammation ensues. Once ASL volume depletion permits mucus adhesion to airway surfaces, reversal of this process will likely require disruption of the strong hydrophobic interactions between secreted mucins and cell surface proteins that mediate mucus adhesion. The administration of a therapeutic aerosol with detergent-like properties, therefore, would be predicted to reverse mucus adhesion and restore MC. Surfactant, a complex mixture of lipids and protein secreted by the distal lung compartment, has a well-defined role in lowering the surface tension of airway lining fluids, thus stabilizing alveoli and small airways. Surfactant also has detergent properties that reduce mucus adhesiveness and promote MC. These properties, along with its long track record of safe exogenous administration, raise the possibility that aerosolized surfactant may be a beneficial therapy for CF lung disease.

This single-center pilot study is designed as a double-blind, randomized, cross-over clinical trial to evaluate the effects of inhaled lucinactant, an investigational peptide-containing synthetic surfactant in patients with mild to moderate CF lung disease. The primary outcome will be the rate of mucus clearance (MCC), as assessed via gamma scintigraphy, post-lucinactant and post vehicle. Secondary outcomes will include the rate of cough clearance (CC), lung clearance index (LCI), absolute change from baseline in FEV1 after 5 doses of study medication, CF-specific quality of life score (via CFQ-R instrument), in vitro assessments of sputum rheology, and various safety parameters.

Targeting Deposition to the Bronchial Airways with Extremely Slow Inhalation in Cystic Fibrosis Patients

(funded by CF Foundation)

Inhaling large (>5 um) particles during extremely slow inhalations (<0.10 Lps) has been shown to bypass the extrathoracic surfaces and deposit in the airways of healthy subjects when compared to respirable (<5 um) particles inhaled during normal tidal breathing (link to pdf download Zeman et al 2011 ref). Such a targeting strategy may prove useful for both assessing mucociliary clearance (MCC) and delivering therapeutic aerosols in CF patients. These studies are currently being extended to CF subjects in our laboratories, including the effect of HS treatment on MCC following delivery by these methods.

Mucinex in Acute Respiratory Infections

A Single Center, Parallel, Double Blind, Placebo Controlled Trial to Assess the Effect of Mucinex (1200 mg GGE) on Mucociliary and Cough Clearance (MCC/CC) during an acute respiratory infection (funded by Reckitt Benckiser):

While Mucinex (and its active ingredient guaifenisen (GGE)) is FDA approved for over the counter use, most of the data supporting its efficacy, mode of action, and pharmacology pre-dates current methods for assessing such expectorants. There is an increasing interest in better understanding how GGE elicits its beneficial effects to help doctors and pharmacists better target the application of GGE for conditions where GGE can be most effective (e.g. bronchial congestion and mucus hypersecretion as seen in many COPD patients).

The primary objective of this study is to assess the biological effect of Mucinex (1200mg GGE) on mucociliary and cough clearance (MCC/CC) during an acute respiratory tract infection in otherwise healthy, non-smoking adults. In addition we will assess sputum properties (objective measures) and symptoms (subjective measures) after GGE treatment compared to matching placebo. Finally, we will also measure plasma concentrations of GGE for pharmacokinetic analysis. Gamma scintigraphy will be used to monitor retention of inhaled, radioactive particles pre- and post-treatment with Mucinex/placebo on the same study day. Any sputum coughed and collected during these measurements will be assessed for mucin content and rheological parameters.

The proposed study design is unique in that it will allow multiple measures of MCC in a given day. By obtaining baseline and post treatment measures of MCC on the same day during an acute exacerbation we should be able to reduce the intersubject variability associated with multi-day measures and the error that this introduces to paired measures in a given subject. This study may set the stage for testing other therapies (e.g. inhaled hypertonic saline or sodium channel blockers) to relieve the symptoms and time course of colds in otherwise healthy individuals.

Endotoxin Inhalation in Healthy and Asthmatic Subjects

A Study of Inhalation of 20,000 EU Clinical Center Reference Endotoxin in Normal Volunteers Compared to Allergic Asthmatic Individuals (funded by NIH)

Among environmental causes of asthma exacerbation, endotoxin is present in airborne particles and is one of the most significant causes of acute disease in persons with established disease. Asthmatics show an impaired ability to clear mucus from their airways, especially during acute exacerbations. We recently showed that mucociliary clearance (MCC) was depressed following dust mite allergen challenge in allergic asthmatics, and was most evident in those individuals who had a late phase response to the allergen (link to pdf download Bennett et al Clinical & Experimental Allergy).

We performed an open label study comparing MCC indices, exhaled nitric oxide, and sputum cells/cytokines on a baseline study day and after inhalational challenge with 20,000 EU Clinical Center Reference Endotoxin (CCRE) in healthy and atopic asthmatic adults. Four (4) hours after inhaled endotoxin challenge we assessed regional lung deposition and subsequent clearance of inhaled, radiolabeled particles by gamma scintigraphy over a 2-hour period. At the conclusion of MCC measurements (6 hours post challenge), exhaled nitric oxide was measured and airway sputum was induced by hypertonic saline induction to recover airway cells/cytokines.

Mucociliary Clearance During Acute Exacerbations of COPD

(funded by NIH)

The purpose of this research study is to learn more about mucus and whether or not its thickness makes it more difficult for people with Chronic Obstructive Pulmonary Disease (COPD)/chronic bronchitis (CB) to clear their lungs. Previous research has demonstrated in diseases such as cystic fibrosis that mucus clearance is a major component of lung defense, and the inability to clear mucus can lead to increased infections. We hypothesize that dehydrated mucus makes it more difficult for COPD/CB patients to clear their lungs. To test this, we will analyze mucus hydration and clearance in patients with normal lung function or early stage COPD. There is also an increased production of mucus in CB, and we hypothesize that this increased mucus production with poor clearance from the airways leads to recurrent exacerbations. To test this, we will analyze mucus clearance in patients with CB at baseline, during an exacerbation and at recovery.

Patients with COPD often have exacerbations which suggest that the mucus clearance process is altered. We hypothesize that an acute exacerbation of COPD reflects a collapse of this mucus clearance and that rehydration with a concentrated salt solution (hypertonic saline) will restore mucus clearance to the baseline state. Hypertonic saline has been shown to improve the clearance of mucus in patients with cystic fibrosis, and this may improve lung function and reduce lung infections. To test this hypothesis in COPD, we will analyze mucus clearance at baseline and during an exacerbation, and we will test if inhaling hypertonic saline will affect mucus clearance at baseline and during an exacerbation.