Bronchiolitis obliterans syndrome (BOS) is a devastating pulmonary complication affecting long-term survivors of allogeneic hematopoietic cell transplantation. Treatment of BOS with prolonged courses of high dose corticosteroids is often associated with significant morbidity. Reducing the exposure to corticosteroids may reduce treatment-related morbidity. Our institution has recently begun to treat patients with emerging therapies in an effort to diminish corticosteroid exposure. We retrospectively reviewed the 6-month corticosteroid exposure, lung function and failure rates in eight patients with newly diagnosed BOS who were treated with a combination of fluticasone, azithromycin and montelukast (FAM) and a rapid corticosteroid taper. These patients were compared with 14 matched historical patients who received high-dose corticosteroids, followed by a standard taper. The median 6-month prednisone exposure in FAM-treated patients was 1819 mg (0-4036 mg) compared with 7163 mg (6551-7829 mg) in the control group (P=0.002). The median forced expiratory volume in 1 s (FEV(1)) change in FAM-treated patients was 2% (-3 to 4%] compared with 1% (-4 to 5%) in the control group (P=1.0). Prednisone exposure in FAM patients was one quarter that of a retrospective-matched group of patients, with minimal change in median FEV(1), suggesting that BOS may be spared of the morbidities associated with long-term corticosteroid use by using alternative agents with less side effects.