PROTOCOL OUTLINE: This is randomized, double blind, placebo controlled study. Patients are randomized to receive beta interferon and thalidomide placebo (arm I), thalidomide and beta interferon placebo (arm II), or placebo for both beta interferon and thalidomide (arm III). Patients receive interferon beta by subcutaneous injection and thalidomide orally. All patients are maintained on glyceryl trierucate and glyceryl trioleate (Lorenzo's oil) therapy.