After the surgical resection of brain tumors, treatments using chemotherapy are typically administered. Unfortunately, most drug molecules barely penetrate into the brain tissue due to the blood-brain barrier (BBB).
The SonoCloud® medical device allows for a temporary disruption of the BBB and thus an increase in the intracerebral bioavailability of chemotherapeutic agents. It can in principle be used for the treatment of primary brain tumors (gliomas, glioblastomas, astrocytomas, …) as well as secondary brain tumors (metastases). The combined annual incidence in Europe and the USA is more than 250,000 patients for these indications.
A phase 1/2a clinical trial has been started to study the transient opening of the BBB with the SonoCloud® before administration of chemotherapy in patients with recurrent glioblastoma. In the long term, the SonoCloud® system can be used for other disorders for which the BBB limits the efficacy of drug therapies (neurodegenerative diseases such as Alzheimer’s).
The SonoCloud® Treatment
The SonoCloud® medical device is implanted in the skull, normally following a surgical resection of the tumor. If the patient cannot be operated on, the SonoCloud® can be implanted in a burr hole performed for a diagnostic biopsy or during a special surgical act under local anesthesia. After implantation, the skin is used to recover the implant. The implant is activated before each chemotherapy session using a transdermal needle that connects the implant to an external generator. The connection to the implant can be performed by a nurse. The ultrasound is emitted directly to the brain tissue, without having to pass the skull, to temporarily open the blood-brain barrier. Finally, even large molecules can be effectively delivered to the brain after disruption of the BBB.
The figure shows the opening of the blood-brain barrier using the SonoCloud® in an animal model. Note the contrast enhancement in the T1w MR image, which shows the region of BBB disruption. After 6 hours, the BBB integrity is restored.