This clinical study evaluates the 12-week efficacy and safety of Epinephrine HFA Inhalation Aerosol HFA the proposed HFA formulation of metered dose inhaler (MDI) of Epinephrine, in comparison to a Placebo-HFA control MDI and the currently marketed Primatene® Mist (epinephrine CFC inhaler), in adolescent and adult subjects with asthma.

Inclusion Criteria:

• Patients with documented asthma, requiring inhaled epinephrine or beta 2-agonist treatment.
• No significant changes in asthma therapy and no asthma-related hospitalization or emergency visits, within 4 weeks prior to Screening
• Can tolerate withholding treatment with inhaled bronchodilators and other allowed medications for the minimum washout period.
• Demonstrating a Screening Baseline FEV1 that is 50 - 90% of predicted normal value.
• Demonstrating at least a 12% Airway Reversibility.
• Demonstrating satisfactory techniques in the use of metered-dose inhaler and a hand held peak expiratory flow meter.
• Female patients of child-bearing potential must be non-pregnant and non-lactating at Screening and throughout the study, and must use an acceptable method of contraception during the study.

Exclusion Criteria:

• A smoking history of 10-pack years, or having smoked within 12 months of screening.
• Any current or past medical conditions that, per investigator discretion, might significantly affect responses to the study drugs, other than asthma.
• Concurrent clinically significant diseases.
• Known intolerance or hypersensitivity to any component of the study drugs.
• Recent infection of the respiratory tract, before screening.
• Use of prohibited medications.
• Having been on other investigational drug/device studies in the last 30 days prior to screening.
• Known or highly suspected substance abuse.