HFA-134a clinical trials

A Study to Compare Safety of 4 Weeks Exposure to Propellants Hydrofluoroalkane 1,1-difluoroethane (HFA-152a) and HFA-1,1,1,2-tetrafluoroethane (134a)

This study looks at how safe two different types of 'propellant' are in asthma inhalers. Propellants are the harmless gases that push the medicine out. We want to check if a new type of propellant is as safe as one already in use for people with asthma.