Pritumumab is a human IgG1 kappa antibody that has been derived from a B-cell isolated from a regional draining lymph node of a patient with cervical carcinoma. Specificity analysis of the antibody with human tissues showed the antigen, altered tumor-associated vimentin, to be highly restricted to various cancers and not normal cells and tissues. In various clinical trials in Japan 249 patients with brain cancer were treated with pritumumab. The overall response rate was between 25-30% with several survivors beyond 5-years post-treatment. The patients were on a low dose regimen of 1mg given twice a week for a course of 24 weeks for a total dose of 48 mgs per course. Pritumumab appears to be a safe and effective therapy in patients with malignant gliomas.