Leflunomide for the Treatment of Multiple Sclerosis: A Case Series
Over the past two decades, fourteen separate branded disease modifying therapies (DMTs), one branded generic and two unbranded generics have been FDA approved, yet the rising cost of DMTs has raised the question whether generic medications approved for other indications should be considered in MS. Leflunomide, the parent compound of teriflunomide, is a selective inhibitor of de novo pyrimidine synthesis approved for the treatment of rheumatoid arthritis (RA) since 1998.
To report a case series of 53 patients treated with leflunomide in five MS centers across the United States, and to describe patient characteristics and reasons for off-label use of leflunomide.
Fifty-three leflunomide-treated patients (85% women) were identified based on chart review at five U.S. MS centers, mean age at leflunomide initiation of 61 years. 64% of patients had relapsing-remitting MS, while 32% had secondary-progressive MS and 2 had primary-progressive MS (formerly, progressive-relapsing MS). Only 17% of patients had comorbid RA, and the leflunomide was being used to treat both the MS and RA; another 6% had comorbid Crohn's disease. Maximum leflunomide exposure was 90 months, with a mean exposure of 24.5 months and median of 17 months. Leflunomide was used as a monotherapy in 54% of patients, and as a low cost adjunct for efficacy in combination with other DMTs 46% of the time. Approximately half (53%) were placed on leflunomide for financial reasons.
Leflunomide, while not FDA-approved for MS, may be a lower cost alternative for patients with access issues in obtaining an MS DMT or in those looking to supplement the efficacy of other approved MS DMTs.