Scleroderma is an autoimmune disease that causes hardening of the skin and connective tissues. The cause is unknown. One complication of scleroderma is interstitial lung disease. This disease, characterized by inflammation (alveolitis) and scarring (fibrosis) of lung tissue, slowly erodes lung function, causing breathlessness and dry cough. Interstitial lung disease is a common cause of death in people with scleroderma.

Preliminary studies suggest that cyclophosphamide, an old drug used to suppresses the immune system, can help preserve lung function in patients with interstitial lung disease. Since there are no other known treatments, many physicians prescribe cyclophosphamide for these patients. However, this drug’s true usefulness is unclear, as randomized, controlled trials—the gold standard for establishing a drug’s safety and efficacy—have not been done.

The purpose of the Scleroderma Lung Study was to determine if cyclophosphamide was in fact useful for patients with scleroderma-related interstitial lung disease. The results of this randomized, controlled trial were published in the June 22, 2006 issue of New England Journal of Medicine . They showed that cyclophosphamide caused small, but significant improvements in lung function compared with placebo, which failed to even prevent further deterioration of lung function.

About the Study

The Scleroderma Lung Study Research Group recruited 158 patients with scleroderma-related interstitial lung disease. The patients were randomly assigned to receive either cyclophosphamide or placebo daily for one year. Lung function was measured every three months and compared between the two groups. Patients were also monitored for a second year, during which neither placebo nor cyclophosphamide was given.

After one year, lung function slightly improved in the cyclophosphamide group, while it continued to decline in the placebo group. The difference between the two groups was significant. The drug’s protective effect persisted at 24 months.

Cyclophosphamide also led to a slight, but significant increase in adverse effects, particularly a drop in the number of infection-fighting white blood cells. This effect resolved with adjustment of the drug’s dosage.

A possible limitation to these findings is the number of people who withdrew from the study, although this number was similar in both groups.

How Does This Affect You?

This study reports a small, but significant improvement in lung function due to cyclophosphamide, providing legitimacy to this treatment for scleroderma-related interstitial lung disease. While the cyclophosphamide group reported slightly more side effects than the placebo group, the researchers believe that the potential benefits outweigh the risks.

If you are living with scleroderma, talk with your doctor to determine if cyclophosphamide is a good choice for you. With this difficult-to-treat condition, even small improvements can be meaningful.

If you have scleroderma, heed the following guidelines to help protect your lungs:

  • Have a thorough lung exam soon after symptoms of skin thickening appear. This exam will include lung function tests, which can detect problems early, when they are potentially more treatable.
  • Report signs of worsening lung function to your doctor:
    • Fatigue
    • Shortness of breath or difficulty breathing
    • Swollen feet
  • Receive flu and pneumonia vaccines regularly, as recommended by your doctor. These conditions are particularly dangerous for a person with lung disease.