- Researchers at Sunnybrook Health Sciences Centre and The Hospital for Sick Children are collaborating on a clinical trial using focused ultrasound in patients with diffuse intrinsic pontine glioma (DIPG).
- DIPGs are highly aggressive and devastating brain tumors that affect young children.
- In this trial, physicians are exploring focused ultrasound-induced blood-brain barrier opening to enhance delivery of chemotherapy to the tumor.
Researchers at Sunnybrook Health Sciences Centre and The Hospital for Sick Children (SickKids) have begun a collaborative clinical trial using focused ultrasound to open the blood-brain barrier (BBB) and deliver chemotherapy in patients with diffuse intrinsic pontine glioma (DIPG).
DIPGs are highly aggressive and devastating brain tumors that affect young children, typically aged 5–9. They affect a region of the brainstem that regulates the body’s involuntary activities such as breathing, heart rate, and swallowing. Only 10 percent of children survive past the two-year mark after diagnosis because current therapies are highly ineffective.
One reason that brain tumors – including DIPG – are challenging to treat is the BBB. This protective layer of tightly joined cells that lines the blood vessels in the brain prevents harmful substances, such as toxins and infectious agents, from diffusing into the surrounding brain tissue. However, it can also prevent therapeutic agents – like chemotherapy – from getting into the brain.
Focused ultrasound has been shown to temporarily disrupt the BBB in a noninvasive, safe, and targeted manner. The ultrasound waves interact with microbubbles in the vessels, causing them to vibrate rapidly and create openings that can enable therapies to pass through.
In this trial, researchers are investigating the safety and feasibility of using Insightec’s Exablate Neuro device to open the BBB in 10 participants between the ages of 5 and 18. Participants will undergo focused ultrasound therapy in conjunction with chemotherapy during three treatment cycles, about four to six weeks apart. The first patient underwent the initial procedure earlier this month.
The trial is being led by Nir Lipsman, MD, PhD, neurosurgeon and director of Sunnybrook’s Harquail Centre for Neuromodulation, and James Rutka, MD, PhD, director of the Arthur and Sonia Labatt Brain Tumour Research Centre at SickKids.
“DIPG is a devastating pediatric brain tumor which is inoperable due to its location in the brainstem,” says Dr. Lipsman. “Focused ultrasound is an innovative and noninvasive approach to more effectively delivering chemotherapy directly to the tumor. Our hope is that this continued research will bring us closer to enhancing treatments to help change the course of the disease.”
Sunnybrook Health Sciences Centre is a Focused Ultrasound Foundation Center of Excellence, and the Foundation is funding a portion of this clinical trial.
If you are interested in learning more about this clinical trial, please contact James Rutka, MD, (416-813-6425, email@example.com) or Maheleth Llinas (416-480-6100 ext 2476, firstname.lastname@example.org).
Additional DIPG Trials in the US
Focused ultrasound is being investigated to address DIPG at other sites in the US. At Children’s National Hospital (CNH) in Washington, DC, a team of researchers is conducting two clinical trials. One approach is similar to the Sunnybrook trial, where focused ultrasound will be used to open the BBB in an effort to deliver chemotherapy to the tumor. The other trial at CNH is testing sonodynamic therapy as a way to destroy the tumor. Both clinical trials are currently recruiting patients. CNH became the Foundation’s first pediatric Center of Excellence in 2020.
Another DIPG clinical trial investigating focused ultrasound-induced BBB opening to deliver chemotherapy began in July 2021 at Columbia University.