Systemic interferon-alpha in the treatment of HTLV-I-associated myelopathy

Treatment with interferon-alpha (IFN-alpha) was undertaken in 16 patients with human T-lymphotropic virus type I-associated myelopathy (HAM). All patients had progressive spastic paraparesis before treatment. Twelve patients were enrolled in an open therapeutic trial with a dose of 3.0 x 10(6) IU/day of IFN-alpha and 4 in a randomized, double-blind, multidose (3.0 x 10(6), 1.0 x 10(6) or 0.3 x 10(6) IU/day) trial. IFN-alpha was injected intramuscularly for 28 days. Eight of 12 patients enrolled in an open trial and 2 patients receiving a dose of 3.0 x 10(6) IU/day of IFN-alpha in a randomized trial showed clinical improvements during and after the treatment. The results showed that, although not for all patients, systemic IFN-alpha with a dose of 3.0 x 10(6) IU/day is effective in the treatment of HAM.