Scleroderma Lung Disease

BACKGROUND:

Systemic sclerosis is a connective tissue disease of unknown etiology characterized by microvascular injury and excessive fibrosis of the skin and viscera. In the United States, 5,000 to 10,000 new cases are diagnosed annually. Approximately 80 percent of these persons will eventually develop some degree of lung involvement, and restrictive lung disease (interstitial fibrosis) is now the leading cause of morbidity and mortality in systemic sclerosis. An inflammatory alveolitis is thought to be the precursor of interstitial pulmonary fibrosis in systemic sclerosis. An effective treatment for SSc interstitial lung disease has yet to be identified. Cyclophosphamide (CYC) is already being widely used by rheumatologists desperate to do something to halt rapidly declining lung function in SSC patients. Thus, the time is ripe to perform a placebo-controlled trial of CYC in this disease.

Pulmonary scleroderma strikes all races and is most prevalent among women during their child-bearing, child-rearing, and working years. A positive outcome from this trial, demonstrating that oral cyclophosphamide has a beneficial effect on pulmonary fibrosis, would be of great importance by offering a scientific basis for treatment. Similarly, a negative result, demonstrating no benefit from cyclophosphamide therapy, would also be important in avoiding hazardous and expensive therapy that is now being used widely.

DESIGN NARRATIVE:

Multicenter, placebo-controlled, randomized, double-blind. Subjects are recruited at 12 clinical centers and randomized to 2 mg/kg/day of cyclophosphamide or placebo. Follow-up visits for pulmonary assessments occur every three months for two years after treatment. If patients fail the cyclophosphamide treatment, they will be offered azathioprine for the remainder of the 24 month trial. The primary endpoint of the study is change in forced vital capacity at the end of 12 months of treatment. Secondary endpoints include quality of life, activity, and dyspnea indices, and carbon monoxide diffusing capacity. Recruitment ends in December, 2003.

Inclusion criteria

• Patients with limited or diffuse systemic scleroderma if they had evidence of active alveolitis on examination of bronchoalveolar-lavage (BAL) fluid (defined as neutrophilia of ≥3 percent, eosinophilia of ≥2 percent, or both)on thoracic high-resolution computed tomography (CT), any ground-glass opacity,
• Onset of the first symptom of scleroderma other than Raynaud's phenomenon within the previous seven years,
• An FVC between 45 and 85 percent of the predicted value
• Grade 2 exertional dyspnea according to the baseline instrument of the Mahler Dyspnea Index (as measured with the use of the magnitude-of-task component).

Exclusion criteria

• A single-breath carbon monoxide diffusing capacity (DlCO) that was less than 30 percent of the predicted value,
• A history of smoking within the preceding six months, other clinically significant pulmonary abnormalities,
• Clinically significant pulmonary hypertension requiring drug therapy.
• Patients taking prednisone at a dose of more than 10 mg per day, those who had previously been treated for more than four weeks with oral cyclophosphamide or had received two or more intravenous doses,
• Patients who recently received other potentially disease-modifying medications.