1st focused ultrasound US study to open blood-brain barrier will help deliver glioblastoma drugs

In the first-of-its-kind FDA-approved study, researchers from the University of Maryland School of Medicine are using MRI-guided focused ultrasound to open the blood-brain barrier to help deliver drugs for patients with glioblastoma.

The study was approved by the FDA in October 2017 and will be conducted with patients undergoing brain cancer surgery at the university’s medical center, according to an Aug. 9 news release.  

Although the blood-brain barrier helps safeguard the brain, it also restrains physicians from delivering disease- and tumor-fighting drugs. In fact, 98 percent of currently FDA-approved drugs do not enter the brain because of the blood-brain barrier, explained lead author Graeme Woodworth, MD, a professor of neurosurgery and director of the Brain Treatment and Research Center at the University of Maryland.  

“The ability to temporarily disrupt the blood-brain barrier without causing tissue damage has the potential to dramatically alter the landscape of drug delivery to the brain for many diseases,” Woodworth said in a statement. “If we can selectively open the blood-brain barrier, then in the future we could give a much lower dose of powerful drugs, which would likely reduce toxic side effects and make treatments safer and more effective for patients.” 

For their study, Woodworth and colleagues will inject gas-filled microbubbles into the bloodstreams of 15 patients with suspected glioblastoma scheduled for brain tumor removal surgery. The researchers will then move the microbubbles back and forth with sounds waves to stretch the blood vessel walls to create temporary openings to allow gadolinium to go into the brain tissue, according the news release.  

“If successful, this approach would allow us to use chemotherapy and other therapies in the brain in ways that are currently not possible,” Woodworth said.  

The MRI data will then be used in an advanced 3D-guidance system called intraoperative stereotactic neuronavigation to correctly confine the tumor within the brain, according to the release. After the tumor removal surgery is complete, researchers will examine the removed tissue to study the effects from the focused ultrasound procedure.  

Woodworth and colleagues believe their research may help increase the amount of navigation data available to surgeons.  

In the next few months, the researchers hope to start another FDA-approved clinical trial of patients with newly diagnosed glioblastoma, which usually has a 15-month life expectancy rate after diagnosis. For this, the patients will undergo blood-brain barrier opening before chemotherapy to target areas of tumor reccurrence.  

“MRI-guided focused ultrasound holds great promise in treating a variety of medical conditions, from cancer to Parkinson’s disease,” said E. Albert Reece, MD, PhD, MBA, dean of the University of Maryland School of Medicine. “Our physician-scientists are leading major research studies and are at the forefront of efforts to determine how this new technology can be used to provide better treatments for patients.” 

The study is sponsored by InSightec, which developed the MRI-guided focused ultrasound technology used in the study, according to the release.