Background: In severe, progressive interstitial lung disease (ILD), specific diagnosis is often difficult, and treatment therefore empirical. An effective, rapidly acting, well-tolerated therapy is desirable. This study reviews the tolerability and efficacy of i.v. cyclophosphamide in known or suspected non-specific interstitial pneumonia (NSIP) following the introduction of an i.v. cyclophosphamide protocol.
Methods: Records of 54 patients with biopsy-proven (n = 7) or suspected NSIP, based on clinico-radiological consensus (n = 47), receiving i.v. cyclophosphamide over 2004-6 were reviewed (excluding systemic sclerosis). Lung-function trends over six months were evaluated, and comparative analysis of paired pulmonary-function before and after the start of therapy was performed.
Results: IV cyclophosphamide was well tolerated, with two withdrawals from therapy, and four deaths, not directly related to treatment. IV cyclophosphamide was associated with disease stability at six-months. Despite having severe, progressive disease, patients receiving i.v. cyclophosphamide had stable lung function at six months. A greater therapeutic response was associated with coexistent HRCT abnormalities indicative of organizing pneumonia. In 22 patients with paired pulmonary-function tests, pulmonary function trends were significantly improved (p = 0.03) and change in DLco differed significantly (p < 0.0001), following cyclophosphamide treatment.
Conclusion: In the empirical treatment of advanced, rapidly progressive known or suspected NSIP, i.v. cyclophosphamide is a well tolerated, rapidly acting immunosuppressant, associated with improvement or stability in most cases.