Malignant gliomas are an especially difficult type of cancer to treat. Manifesting in the brain or spine, patients diagnosed with this deadly form of cancer have only a 3 percent likelihood of surviving five years or more. Now, a new method for delivering chemotherapy drugs is showing early signs of prolonging survival times among patients with malignant glioma.This new delivery process, called convection enhanced delivery, uses two catheters that are stereotactically placed in the tumor tissue to directly deliver Topotecan to the cancerous area.
Of the 16 patients who received the Phase 1 trial treatment, the median survival was 59 weeks. Furthermore, the median time to tumor progression was recorded at 20 weeks, and more than three-fourths of all patients survived for at least 6 months. These figures were statistically much better than those found in present treatment processes.
The direct chemotherapy process was formulated to overcome a poor penetration rate of intravenous and oral cancer drugs related to brain tumors. Due to a blood-brain barrier, the majority of drugs in the bloodstream never enter the brain. Additionally, surgery is not typically an effective treatment method because gliomas tend to grow tentacles that make them very difficult to remove completely.
Topotecan, a chemo drug currently used for lung cancer and sold by GlaxoSmithKline, was chosen for the trial because it has been shown to be effective in killing malignant glioma cells. However, the amount of Topotecan required in standard treatment procedures to adequately penetrate the brain was deemed too toxic for normal cells.
Though the new treatment has achieved early success, additional studies are required. Phase 2 clinical trials will begin in the coming months. Side effects presently linked to the new treatment include weakness in the upper extremities and neurological issues that occur due to brain damage.