A Randomized Phase III Trial of Memantine and Whole-Brain Radiotherapy With or Without Hippocampal Avoidance in Patients With Brain Metastases

This randomized phase III trial compares memantine hydrochloride and whole-brain radiotherapy
with or without hippocampal avoidance in reducing neurocognitive decline in patients with
cancer that has spread from the primary site (place where it started) to the brain. Whole
brain radiotherapy (WBRT) is the most common treatment for brain metastasis. Unfortunately,
the majority of patients with brain metastases experience cognitive (such as learning and
memory) deterioration after WBRT. Memantine hydrochloride may enhance cognitive function by
binding to and inhibiting channels of receptors located in the central nervous system.
Radiation therapy uses high energy x-rays to kill tumor cells and shrink tumors. Using
radiation techniques, such as intensity modulated radiotherapy to avoid the hippocampal
region during WBRT, may reduce the radiation dose to the hippocampus and help limit the
radiation-induced cognitive decline. It is not yet known whether giving memantine
hydrochloride and WBRT with or without hippocampal avoidance works better in reducing
neurocognitive decline in patients with brain metastases.