The efficacy of inhaled corticosteroids (ICS) in asthmatic subjects showing no sputum eosinophils is controversial. The broad aim of this study is to assess whether ICS alone or in combination with long-acting beta-2 agonists are an effective treatment in non-eosinophilic asthmatic subjects. Methods: The investigators will perform a randomized double-blind, placebo-controlled, multicenter study comparing the efficacy of ICS and placebo for 4 weeks followed by a 4-week open treatment period with ICS/salmeterol in steroid-naïve asthmatic subjects without sputum eosinophilia. The primary outcome will be the the Asthma Control Questionnaire (ACQ) score after four weeks of treatment by ICS or placebo.