Canada. Aventis Pharma Inc. have issued a "Dear Healthcare Professional" letter highlighting important safety information regarding reports of interstitial lung disease associated with leflunomide. The letter advises that leflunomide, indicated for the treatment of active rheumatoid arthritis in adults, has been associated with rare spontaneous reports of interstitial lung-disease, reported in 0.19 per 1000 person-years' exposure. In a Japanese post-marketing surveillance programme involving 3658 patients receiving leflunomide, interstitial lung disease was reported in 0.8% of patients, with 29 cases of interstitial pneumonitis, 11 of which had a fatal outcome. Causality assessment was complicated in these cases due to the presence of confounding factors such as pre-existing lung disease and/or previous or concomitant use of other disease-modifying antirheumatics known to be associated with interstitial lung disease. The "Precautions", "Adverse Reactions" and "Information for the Consumer" sections have been updated with this safety information. (See also WHO Pharmaceuticals Newsletters Nos. 9/10, 1998; 2&3, 2001; 1, 2003; 4, 2003).
Reference:
"Dear Healthcare Professional" letter from Aventis Pharma Inc., 21 June 2004. Available on the Internet at www.hc-sc.gc.ca