Retrospective evaluation of interferon-beta treatment in subacute sclerosing panencephalitis.

BACKGROUND: Few effective treatment methods are available for subacute sclerosing panencephalitis (SSPE),an infection associated with the measles virus. Interferons have shown some benefit in previous studies and clinical practice. OBJECTIVE: The purpose of this study was to compare the efficacy of 2 different regimens of interferon-beta(IFN-beta) in the treatment of SSPE in pediatric patients. METHODS: We retrospectively compared the results obtained with 2 regimens of IFN-beta1a: 60 microg administered intramuscularly once weekly (IFN-beta 1/wk), or 22 microg administered subcutaneously 3 times per week (IFN-beta 3/wk). All patients also received oral inosiplex 50 to 100 mg/kg daily, a treatment known to have partial efficacy in SSPE. Patients who continued treatment for at least 3 months and had at least 1 year of follow-up data were evaluated. Clinical parameters included the Neurological Disability Index (NDI), a measurement of mental, motor, and sensory functions; disease stage; and mental status. Data obtained at 6 and 12 months were compared with those at the time of diagnosis, and the percent change from baseline was calculated. A satisfactory clinical response was defined as reduction or stabilization of the NDI or stage improvement at 6 or 12 months. RESULTS: Patients treated with IFN-beta 3/wk had increased survival time (P < 0.02) and higher clinical response rates compared with those treated with IFN-beta 1/wk (P < 0.05). When stage 2 and stage 3 patients were evaluated separately, survival was significantly longer (P = 0.007) and the rate of progression slower in both stage groups with IFN-beta 3/wk. CONCLUSION: The results obtained for this patient sample suggest that IFN-beta administered subcutaneously times per week combined with inosiplex may be an effective treatment option in SSPE. This treatment regimen warrants further study.