Phase I/II study of an implantable device delivering low intensity pulsed ultrasound (LIPU) to disrupt the blood-brain barrier (BBB) followed by intravenous carboplatin chemotherapy in patients with recurrent glioblastoma (GBM).

2034Background: The BBB prevents the passage of most drugs from the blood to the brain and may be responsible for the limited efficacy of current chemotherapies in GBM patients. Two to four minutes of LIPU in combination with injection of micron-sized microbubbleshas been shown to be a safe method for disrupting the BBB for a duration of 6 hours to increase the passage of drugs such as carboplatinby 5 to 7 fold in normal brain. Methods: Patients with recurrent GBM were implanted with a 1 MHz, 10-mm diameter pulsed ultrasound device in a burr hole during additional debulkingsurgery or during a dedicated procedure under local anesthesia. Ultrasound dose was escalated using a 3+3 Simon design. The device was activated monthly in combination with injection of a sulfur hexafluoride microbubbleto transiently disrupt the BBB in 5 cm3 of the tumor field before IV administration of carboplatinchemotherapy (AUC4-6). Patients received 150-270 seconds of pulsed ultrasound < 1 hour prior to chemotherapy. BBB disr...