Optimal airway antimicrobial therapy for cystic fibrosis: the role of inhaled aztreonam lysine

Areas covered in this review: This review describes the development (2003 - 2010) of aztreonam lysine 75 mg powder and solvent for nebulizer solution (AZLI; Cayston<SU (R)</SU), an aerosolized formulation of the monobactam antibiotic aztreonam. What the reader will gain: AZLI was studied in patients with CF and chronic P. aeruginosa airway infection. In placebo-controlled trials, AZLI improved respiratory symptoms, increased forced expiratory volume in 1 sec (FEV1), decreased sputum P. aeruginosa density, and was well tolerated. An open-label follow-on trial of nine 'on/off' courses showed that AZLI was safe and the effect durable with repeated administration. AZLI was recently approved for use in CF patients in Australia and the USA, and conditionally approved in Canada and the European Union. AZLI is given three times daily for 28 days (2 - 3 min/dose), followed by 28 days off-drug. AZLI is used only with the Altera Nebulizer System (TM), which provides appropriate particle size and small airway deposition, and has excellent portability. Take home message: AZLI is a new therapy that is safe and effectively improves respiratory symptoms and FEV1 in patients with CF.