Interstitial Drug Therapy for Brain Tumors: A Case Study

Abstract

A novel method of delivering cancer chemotherapeutic drugs to the brain in concentrations higher than those achievable by standard routes of administration has been developed. The drug was incorporated into wafers (trademarked BIODEL®) of a biodegradable, biocompatible polymer. The drug chosen for initial studies was BCNU (carmustine, 1,3-bis[2-chloroethyl]-1-nitrosourea), the most widely used chemotherapeutic agent for the disease to be treated, glioblastoma multiforme, a universally fatal form of brain cancer. Preclinical studies in a number of species demonstrated the safety of this material implanted either directly into the brain or subcutaneously. Efficacy studies in rats demonstrated that implanting BIODEL® wafers containing BCNU either at the time of tumor implantation or after 4 days of tumor growth could significantly prolong survival of the animals, while greatly diminishing side effects of the BCNU therapy.

The safety of this material implanted into these patients during a Phase I/II study has been demonstrated. No systemic side effects of doses of BCNU which would produce marked effects on the hemopoeitic system when injected intravenously have been observed. Further studies, designed to measure the efficacy of this approach to the treatment of brain cancer in a multicentered Phase III clinical trial in the United States and Canada, are currently underway.