- Reversibility of Disease: Demonstrated ³12% and 200mL reversibility of FEV1 within 30 minutes following 200 to 400mcg of albuterol/salbutamol inhalation aerosol (or one nebulized albuterol/salbutamol treatment) at Visit 1. If a subject fails to demonstrate an increase in FEV1 of ³12% and 200mL, the subject is not eligible for the study and will not be allowed to re-screen.