Effect of Pre-Treatment With Cromolyn or Albuterol on Response to PUL-042 Inhalation Solution (PUL-042)

Healthy subjects (8 per cohort) will be randomized to either pre-treatment or no
pre-treatment (4 per group). The initial cohort will receive pre-treatment with cromolyn
sodium. Subjects will be followed for 2 weeks for safety and tolerability, undergo a 2 week
washout period and then be assigned to the alternative treatment (i.e., subjects who
received cromolyn sodium prior to PUL-042 inhalation solution will not receive pretreatment)
and then followed for an additional 2 weeks.

Subsequent cohorts will receive pre-treatment with albuterol sulfate in a like manner.

Inclusion Criteria:

- Males or females of non-childbearing potential (defined as surgically sterilized
[tubal ligation/hysterectomy/bilateral salpingo oophorectomy or post- menopausal for
> 2 years) with a negative urine human chorionic gonadotropin (hCG) pregnancy test at
the Screening Visit

- Body Mass Index (BMI) between 18 and 30 kg/m2

- Ability to perform spirometry according to American Thoracic Society standards

- Normal spirometry (forced expiratory volume in 1 second [FEV1] and forced vital
capacity [FVC] ≥ 80% and ≤ 120% based on predicted values) at the Screening Visit and
at Visit 2.

- Pulse oximetry ≥95% on room air

- Ability to understand and give informed consent

- Males willing to practice contraception (condom + spermicide) during the study and
for 30 days after completion of the

Exclusion Criteria:

- Febrile (temperature ≥ 99.5°Fahrenheit)

- A history of use of any tobacco products during the year prior to the Screening Visit
and a total exposure of > 5 pack years or a positive urine cotinine level at the
Screening Visit

- Clinically significant laboratory finding as determined by the Principal Investigator
or designee at the Screening Visit or at Visit 2

- Positive test for drugs of abuse (alcohol, cannabinoids, opiates, cocaine,
amphetamine, barbiturates, benzodiazepine, phencyclidine)

- Any active medical problems requiring treatment

- Subjects who exhibit symptoms of respiratory infection or have experienced
respiratory symptoms of an upper respiratory infection within 30 days prior to the
Screening Visit.

- History of chronic pulmonary disease (eg, asthma [including atopic asthma, exercise
induced asthma, or asthma triggered by respiratory infection], pulmonary fibrosis),
pulmonary hypertension, or heart failure

- Any out of range QTc Fridericia (QTcF) or other clinically significant ECG findings
as determined by the Principal Investigator or designee at Visit 2 or Visit 12.

- History of atopic reactions

- Administration of any anti-inflammatory therapy (eg, no steroidal anti-inflammatory
drugs or corticosteroids) within 4 weeks prior to randomization or expected to be
ongoing during the study

- An anticipated need for use of any inhaled medication during the study

- Intake of coffee, tea, cola drinks, chocolate on days of Study Visits 1-21

- Intake of alcohol, caffeine or strenuous exercise within 72 hours prior to study drug
administration or intake of grapefruit within 7 days prior to the administration of
study drug

- Intake of alcohol within 4 hours of spirometry; smoking within 1 hour of spirometry;
performing vigorous exercise within 30 minutes of spirometry; wearing clothing that
substantially restricts full chest and abdominal expansion; or eating a large meal
within 2 hours of spirometry

- Administration of any over the counter (OTC)/prescription medication, supplements,
herbals or vitamins within 14 days prior to study drug administration. Administration
of Tylenol within 72 hours of study drug administration (doses up to 2g/day will be
allowed prior to 72 hours before study drug administration)

- Exposure to any investigational agent within 30 days prior to the Screening Visit

- Receipt of a flu vaccine in the last 3 months

- Prior exposure to PUL-042

- Known positive for human immunodeficiency virus, or on active anti-retroviral therapy
and known hepatitis B surface antigen positive or hepatitis C positive