In this study, 28 subjects with CTD-ILD received MMF for nearly 36 patient-years. MMF was very well tolerated; only two patients discontinued MMF for any reason. In contrast, prior to being started on MMF, 15 patients discontinued other immunomodulatory agents, most because of adverse effects. In addition, MMF maintained pulmonary physiology without increasing the median daily dose of glucocorticoids. Values for FVC, TLC, and Dlco did not decrease while patients were receiving MMF. In fact, clinically significant increases in these values were seen in nine patients as a result of MMF therapy. read only
To our knowledge, this is the first study examining the use of MMF specifically for the ILD component of CTD. Stratton and colleagues treated 13 patients with recently diagnosed diffuse scleroderma with a regimen of MMF and antithymocyte globulin. They found that FVC% and Dlco% remained stable over 12 months. However, the number of patients with ILD at study entry or completion was not reported. In that study—despite using similar doses of MMF (1,800 mg/d) to our cohort (2,000 mg/d)— 43% of patients had adverse effects from MMF, and 16% of patients discontinued MMF because of adverse effects. We observed MMF to be extremely safe and well tolerated in our cohort. Treiber described a patient with recurrent ILD associated with ulcerative colitis. The patient had ILD that was refractory to therapy with AZA and CYC; however, MMF led to improvements in chest CT findings, pulmonary physiology, and measures of gas exchange, along with a dramatic reduction in daily oral glucocorticoid dose. Based on that case report and other data suggesting that MMF suppresses primary human lung fibroblast proliferation in vitro, Altschuler speculated that MMF would be a reasonable therapy for IPF, a devastating fibrosing lung disease of unknown etiology and with pathologic features sometimes found in patients with CTD-ILD.