Leflunomide for Musculoskeletal GVHD After Allogeneic Stem Cell Transplant

Graft versus host disease (GVHD) is a well-known complication of allogeneic transplant. In GVHD, the cells of the donor attack the patient's tissues and cause damage. It can affect any organ or system of the body. In a proportion of patients, it affects the joints and muscles. This is known as musculoskeletal GVHD. The standard treatment of musculoskeletal GVHD is steroids. However, these are usually needed for prolonged periods, and cause a large number of additional problems in transplant patients. Leflunomide is a drug which has been used for several years in diseases like rheumatoid arthritis (RA). RA is an auto-immune disorder. The biological mechanisms underlying RA and musculoskeletal GVHD are quite similar. Hence it is likely that leflunomide may work in musculoskeletal GVHD also. The investigator have previously used leflunomide in a few patients with musculoskeletal GVHD and have found it to be extremely effective. Also, it was very safe (unlike steroids). Yet another advantage is that it is fairly cheap. The purpose of the current study is to study the efficacy and safety of leflunomide in patients with musculoskeletal GVHD in a prospective way.