Cyclophosphamide pulse therapy in idiopathic
pulmonary fibrosis.
Kolb M, Kirschner J, Riedel W, Wirtz H, Schmidt M
Dept of Medicine, University of Wurzburg, Germany.
Idiopathic pulmonary fibrosis (IPF) is a progressive disorder with poor
prognosis. Response to treatment is infrequent and the use of
immunosuppressive agents other than corticosteroids is the subject of
ongoing discussion because of uncertain efficacy and side-effects. To
determine the efficacy and safety of cyclophosphamide pulse therapy in
IPF, this study retrospectively analysed 18 patients with progressive
IPF who were treated with intermittent i.v. cyclophosphamide (1-13 g x
month(-1)) and additional oral prednisolone for 1 yr. Static lung
volumes, arterial oxygen tension (Pa,O2) at rest, clinical symptoms and
potential treatment-related side-effects were recorded. Cyclophosphamide
had to be stopped in one patient, owing to repeated pulmonary infection;
11 patients were responders (five improving, six stabilizing) and six
patients deteriorated. The change in vital capacity (VC) of responders
was +6.7+/-18.0% (mean +/-SD), compared with -20.6+/-18.2% in
nonresponders (p=0.008). Pa,O2 remained constant in responders
(+0.13+/-0.88 kPa (+1.0+/-6.6 mmHg)), while it decreased in
nonresponders (-2.08+/-1.92 kPa (-15.6+/-14.4 mmHg, p=0.008)).
Additional prednisolone was reduced by 19.1+/-13.4 mg in responders,
compared with 6.7+/-16.3 mg in nonresponders (p=0.02). VC at initiation
of therapy was higher in responders (60.2+/-10.2 versus 40.3+/-12.9%
predicted; p=0.004). No side-effects occurred, other than respiratory
tract infection. These data demonstrate that intravenous
cyclophosphamide pulse therapy may be a favourable regimen for certain
patients with progressive idiopathic pulmonary fibrosis. Patients with a
vital capacity of more than 50% predicted and a shorter duration of
disease may benefit most.