Patent ID: 8877164

Claim:
An aerosol formulation consisting of: a 20-ketosteroid; a liquefied HFA propellant, a co-solvent selected from pharmaceutically acceptable alcohols; and an agent selected from the group consisting of phosphoric acid present in an amount equivalent to 0.0004 to 0.040% w/w of 15 M phosphoric acid, based on the total weight of the formulation and sulphuric acid present in an amount equivalent to 0.0005 to 0.02% w/w of 0.075 M sulphuric acid, based on the total weight of the composition that sequesters a metal ion present in the formulation, thereby improving the chemical stability of the active ingredient; wherein said co-solvent is ethanol; and, wherein said formulation is in the form of a solution in which said 20-ketosteroid is completely dissolved.