Use of intravenous cyclophosphamide in known or suspected, advanced non-specific interstitial pneumonia

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.

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.

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.

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.