Bronchoprovocation Study to Demonstrate the Pharmacodynamic Bioequivalence of Albuterol Sulfate HFA Inhalation Aerosol (E.Q. 90 mcg of Albuterol Base/Inh) of Macleods Pharmaceuticals Ltd

Who cannot join

• 1.Subjects with FEV1 \< 1.5L during methacholine challenge test 2.Evidence of upper or lower respiratory tract infection (e.g., pneumonia, bronchitis, sinusitis) within six weeks prior to the study.
• 3.History of seasonal asthma exacerbations, in which case the subject should be studied outside of the relevant allergen season 4.History of cystic fibrosis, bronchiectasis or other respiratory diseases other than asthma (e.g., COPD, interstitial lung disease) 5.Treatment in an emergency room or hospitalization for acute asthmatic symptoms within past three months prior to screening visit 6.Need for daily oral corticosteroids within past three months prior to screening visit 7.History of life-threatening asthma leading to hospitalization within the past 1 year prior to screening visit 8.Known intolerance or hypersensitivity to any component of the albuterol metered dose inhaler (MDI) 9.Uncontrolled hypertension (systolic BP \>200 mmHg, or diastolic BP \>100 mmHg) 10.History or evidence of myocardial infarction or stroke 11.History of known aortic aneurysm 12.Current use of cholinesterase inhibitor medication (for myasthenia gravis) 13.Clinically significant ECG recording at screening such as flattening of T wave, prolongation of QTc interval (\>450 milliseconds), and ST segment depression, which in the opinion of the Investigator, would compromise subject's safety or interfere with the study results 14.History of recent eye surgery or intracranial pressure elevation risk 15.Uncontrolled diabetes (HbA1c ≥9%) at screening 16.Evidence or history of clinically significant disease or abnormality including congestive heart failure, uncontrolled artery disease, cardiac dysrhythmia, or ECG with evidence of ischemic heart disease. In addition, historical or current evidence of significant hematologic, hepatic neurologic, psychiatric, renal, or other disease or that, in the opinion of the Investigator, would put the subject at risk through study participation, or would affect the study analyses if the disease exacerbates in the study 17.Presence of any abnormal clinically significant laboratory investigation at screening visit 18.History of paradoxical bronchospasm 19.Has participated in another investigational study or device research study within 30 days before screening visit date 20.Women are pregnant, breast-feeding, or planning pregnancy during study
• Period continuation criteria If subject does not meet any one Period continuation criteria at any visit of Period; retest visit will be conducted and study treatment dosing should not be administered. Period continuation criteria will be checked for maximum three visits.
• If subject does not meet all Period continuation criteria at any one visit and within three consecutive visits:
• At Period 1: subject should not be randomized and will be considered a 'randomization failure' At Period 2 to Period 4: subject should not administer study treatment dosing and must be discontinued from the study
• Baseline FEV1 should not be less than 70% of predicted normal value and should be within 88 -112% of qualifying day FEV1 value.