Micro-bubbles Allows Drug Delivery to the Brain
9/15/16 There was a recent article in Medical Physics Web that pertained to micro-bubbles being used to penetrate the difficult blood-brain barrier to get drugs delivered to a brain tumor. MES loves hearing about micro technology so we found this article very fascinating and we are excited at the technological advances that are currently taking place in the medical and pharmaceutical fields.
The blood-brain barrier (BBB), a protective layer of cells, limiting the delivery of most drugs into the brain is the reason why brain diseases are so hard to effectively treat. This new research combines pulsed ultrasound with injected microbubbles that vibrate in response to these sound waves to temporarily open the BBB.
This implantable ultrasound transducer is attached to the skull. It has no internal energy source, making it MRI-compatible, and is powered externally by a transcutaneous needle that is connected during treatment sessions.
This device has been tested in patients with recurrent glioblastoma (an aggressive and difficult to treat brain tumor). Preliminary results indicate that the device can safely disrupt the BBB and boost the amount of drug delivered to the brain.
“The blood-brain barrier is one of the last major frontiers of neuroscience,” said Carpentier, one of the researchers. “The publication of the trial results in one of the most prestigious US scientific journals is a major acknowledgment of this medical first.”
The device was implanted into patients divided into groups, each group getting a different acoustic pressure in order to determine at what pressure the BBB becomes disrupted. It was found that a starting pressure of 1.1 MPa was the most successful and detectable adverse side effects were not noticed. The trial is still ongoing to determine the maximum tolerated pressure. Preliminary findings suggest the approach is safe and well tolerated in patients with recurrent glioblastoma and has the potential to optimize chemotherapy delivery in the brain. It was also assessed that the patients that had confirmed BBB disruption had no detected tumor progression. While clinical trials continue, the thoughts of what other brain-related illnesses that can be effected by this new technology is very exciting!