Study terminated due to lack of care guidelines in the protocol.

This study is designed to show that pharmacotherapy guided by eNO and clinical standard of care produces a superior outcome to trial-based therapy guided by clinical standard of care alone.

Patients with persistent, moderate to severe asthma will be randomized to receive therapy guided by either eNO and clinical standard of care (eNO group) or clinical standard of care (control group). An eNO treatment algorithm will be established for each patient in the eNO group at Baseline (Visit 1). Enrollment is estimated to be six months with a follow up period of twelve months.

Inclusion Criteria:

• Pre-existing diagnosis of asthma
• Persistent, moderate or severe asthma as classified by NAEPP
• Sub-optimally controlled asthma
• Initiated ICS therapy for at least the past 30 days and a history of improvement of asthma control on steroids

Exclusion Criteria:

• Active cigarette smoking or ≥ 10 pack-years smoking history
• Xolair taken in the past 6 months prior to enrollment
• Oral prednisone taken in the last 4 weeks prior to enrollment
• Cystic Fibrosis, COPD, ciliary dyskinesia, chest wall deformities or scoliosis
• Subject is currently enrolled in another investigational drug study