Treatment of pulmonary fibrosis for twenty weeks with imatinib mesylate in a patient with mixed connective tissue disease.

Interstitial lung disease, which is common in patients with mixed connective tissue disease (MCTD), can progress to severe pulmonary fibrosis. The tyrosine kinase inhibitor imatinib mesylate has recently been shown to prevent experimental pulmonary, dermal, and renal fibrosis. Our patient, a 64-year-old woman with MCTD and rapidly progressive pulmonary fibrosis, presented with rapid deterioration despite treatment with immunosuppressants. During 20 weeks of treatment with imatinib mesylate at 400 mg/day, our patient improved significantly according to several outcome measures, including New York Heart Association classification, diffusing capacity for carbon monoxide, 6-minute walking distance, arterial oxygen pressure, and reduction of ground-glass opacities seen on high-resolution computed tomography. No adverse effects of imatinib mesylate were observed. These findings suggest that imatinib mesylate might be effective in patients with fibrotic diseases and warrant the initiation of larger clinical studies on the safety and efficacy of imatinib mesylate in connective tissue diseases.