Adequate pharmacological treatment controls symptoms in most asthmatics. Pressurized metered dose inhalers (pMDI)are the most used drug delivery devices. Valved holding chambers of different types and sizes have also been developed for use in combination with pMDI. The therapeutic efficacy of treatment depends on the amount of inhaled particles. The chambers can optimize lung deposition as it obviates lung-hand coordination and retain larger particles. The aim of this study is to compare the efficacy of the fine particle combination pMDI Beclomethasone/Formoterol in asthma control,with or without the aid of a spacer in patients without adequate asthma control on medium to high-dose inhaled steroids associated with long acting beta adrenergic drugs. The hypothesis is that there is no clinical efficacy difference between the two forms of drug administration.