Inhaled medications are often used to treat lung diseases such as cystic fibrosis. We are performing this study to determine whether inhaled medications dissolved in surfactant-based solutions will distribute more evenly throughout the lungs when compared to standard saline-based solutions. We think that inhaling medication that is in a surfactant-based liquid will result in more medication reaching partially blocked parts of the lung. This study will use a special nuclear medicine test called an aerosol deposition scan to compare how a drug spreads in the lung using a surfactant-based aerosol compared to a saline-based aerosol.

Cystic fibrosis (CF) is an inherited chronic disease that affects the lungs and digestive system of about 30,000 children and adults in the United States (70,000 worldwide). The lungs of a person with cystic fibrosis often contain thick sticky mucus that can clog the lungs and lead to life-threatening lung infections. A major milestone in the treatment of CF was the development of an inhaled form of an antibiotic drug called tobramycin. For an inhaled antibiotic to work it must be delivered to all infected parts of the lung. Many studies have shown that blockages in the lungs, like those found in CF patients, can prevent inhaled medicines from reaching all parts of the lungs.

Usually aerosolized medications are dissolved in saline or water. Most of these medications could be dissolved in surfactant solutions and aerosolized. Soaps are common examples of surfactants. Surfactants may have the ability to spread medication over the inside surface of the lungs similar to the way dish soap spreads over water. We think that inhaling medication that is in a surfactant-based liquid will result in more medication reaching partially blocked parts of the lung. We further believe that the normal movements of the lung associated with breathing will further spread surfactant-based aerosol medications, and contribute to even more even drug distribution over longer periods of time.

A surfactant-based inhaled antibiotic would have the potential to reach more sites of infection in the lung, possibly getting rid of infection all together. This study will use a special test called an aerosol deposition scan to compare how a drug spreads in the lung using a surfactant-based aerosol compared to a saline-based aerosol. The study includes one screening and two testing visits.

Inclusion Criteria:

• Age ≥ 18 years
• Diagnosis of cystic fibrosis as determined by sweat test or genotype and clinical symptoms
• Clinically stable as determined by the investigator (pulmonologist).

Exclusion Criteria:

• Known allergies to any of the administered components (as described by subjects or based on positive RAST test to bovine serum albumin)
• Any past instances of bronchospasm associated with aerosol medications
• FEV1 < 60% predicted
• Positive urine pregnancy test (as administered to all female subjects of childbearing potential on testing days)
• Currently a nursing mother
• History of reactive airways disease associated with significant instances of bronchoconstriction
• Self-reported smoking history within the last 6 months.
• Subjects receiving any treatments or diagnostic procedures involving radioisotopes within the last 30 days.
• Subjects in the CF arm of the study will also be excluded if their pre-study pulmonary function test (FEV1) is more than 15% depressed from their last baseline pulmonary function test, if this baseline value is from within the last 6 months, or if they have experienced an exacerbation requiring hospitalization or treatment with an IV antibiotic within the last month.

Cystic fibrosis subjects

Our aerosol delivery method resulted in more peripheral distribution than was anticipated. The more peripheral deposition pattern likely affected the location and quantity of deposited calfactant available to cause transport.