Escalating and Cumulative-Dose Study of Pharmacokinetics (PK), Pharmacodynamics (PD) and Safety of A006

Inclusion Criteria:

- Body weight ≥ 50 kg for men and ≥ 45 kg for women, and BMI within the range of 18.5 -
30.0 kg/m2 inclusive;

- Sitting blood pressure ≤ 135/90 mmHg;

- Demonstrating negative alcohol/drug screen tests;

- Demonstrating negative HIV, HBsAg and HCV-Ab screen tests;

- With mild-to-moderate persistent asthma for at least 6 months prior to Screening, and
having used inhaled β-agonist(s) for asthma control;

- Demonstrating a Mean Screening Baseline FEV1 at 50.0 - 85.0 % of predicted normal;

- Demonstrating a ≥ 15.0% Airway Reversibility in FEV1 within 30(±5) min after inhaling
2 actuations of Proventil® MDI;

- Demonstrating Peak Inspiratory Flow Rate within 80-150 L/min;

- Demonstrating proficiency in the use of DPI and MDI after training;

- Females of child-bearing potential must be non-pregnant, non-lactating, and
practicing a clinically acceptable form of birth control;

- Having properly consented to participate in the trial.

Exclusion Criteria:

- Smoking history of ≥ 10 pack-years, or having smoked within 6 months prior to
Screening;

- Upper respiratory tract infections within 2 wk, or lower respiratory tract infection
within 4 wk;

- Asthma exacerbations that required emergency care or hospitalized treatment, within 4
wk prior;

- Any current or recent respiratory conditions that might significantly affect
pharmacodynamic response to the study drugs, besides asthma;

- Concurrent clinically significant cardiovascular, hematological, renal, neurologic,
hepatic, endocrine, psychiatric, malignancies, or other illnesses that could impact
on the conduct, safety and evaluation of the study;

- Known intolerance or hypersensitivity to any of the ingredients of the study drug DPI
or Proventil® MDI;

- Use of prohibited drugs or failure to observe the drug washout restrictions;

- Having been on other clinical drug/device studies in the last 30 days;

- Having donated blood within the last 30 days prior to Screening.