No Excess Risk for Lung Disease in Leflunomide-Treated Patients with Rheumatoid Arthritis

Both methotrexate and leflunomide are used to treat patients with rheumatoid arthritis (RA). Many reports have suggested an association between leflunomide and lung toxicity, but actual incidence of such toxicity is unclear. Also, because RA itself has pulmonary manifestations, determining the relation between these medications and adverse pulmonary events is difficult. In 2014, a meta-analysis showed an association between methotrexate and excess risk for adverse infectious (but not noninfectious) pulmonary complications (NEJM JW Gen Med Jun 1 2014 and Arthritis Rheumatol 2014; 66:803). In a new meta-analysis, researchers evaluated data on adverse pulmonary events in eight randomized, controlled trials (mean duration, 55 weeks) of leflunom…