Abstract

Radioimmunotherapy ( RIT) may improve the management of malignant gliomas. A Phase I clinical trial was performed to evaluate, for the first time, the toxicity and clinical effect of an intracavitary administration of a single dose of Nimotuzumab (h-R3) labeled wit (188)Re. Nimotuzumab is a humanized monoclonal antibody directed against epidermal growth factor receptors. Three patients with anaplastic astrocytoma ( AA) and 8 with glioblastoma multiforme ( GBM) were intended to be treated with 3 mg of mAb labelled with 10 or 15 mCi of (188)Re. In patients treated with 10 mCi ( n = 6) transitory worsening of pre-existing neurological symptoms were observed. Two patients treated with 15 mCi ( n = 4) developed early severe neurological symptoms and one also developed late severe toxicity ( radionecrosis). In the group treated with 10 mCi, 1 GBM patient died in progression 6 months after the treatment, 2 patients ( 1 GBM and 1 AA) developed stable disease during 3 months. One GBM patient had partial response for more than 1 year and 2 patients ( 1 GBM and 1 AA) were asymptomatic and in complete response after 3 years of treatment. Maximal tolerated dose of the radioimmunoconjugate (188)Re-Nimotuzumab was 3 mg of the h-R3 labelled with 10 mCi of 188Re. The radio-immunoconjugate showed a high retention in the surgical created resection cavity and the brain adjacent tissues with a mean value of 85.5% of the injected dose one hour post-administration. This radioimmunoconjugate may be relatively safe and a promising therapeutic approach for treating high grade gliomas.