Brain tumor ‘monorail’ lands FDA breakthrough device nod
Brain tumor ‘monorail’ lands FDA breakthrough device nod

A “tumor monorail” that lures aggressive brain tumor cells to their death in an external container has won “breakthrough device” designation from FDA.

The purpose of the device is not to destroy the glioblastoma tumor, but to halt its lethal spread, making the disease more of a condition to manage than a death sentence, according to researchers at Duke University’s Pratt School of Engineering.

The device works by mimicking the physical structures of the brain’s white matter, where it travels through a narrow opening connecting the left and right hemispheres, a popular growth track for glioblastoma. It is made of aligned polycaprolactone (PCL) nanofiber films that lead from the tumor to a container on top of the skull just under the scalp, where the cancer cells die and can be removed. There are no chemicals or enzymes involved, and the device can be made of a wide variety of materials,

Developed by researchers at Georgia Tech and Emory University, the tumor monorail first made headlines in 2014 in an exploratory study published in Nature Materials, showing that the concept was effective in rat models. A prototype device successfully played Pied Piper to glioblastoma cells, enticing them to migrate toward a repository filled with a toxic gel. The tumors’ spread slowed and they shrank by more than 90 percent.

In its current iteration, the device resembles a long, thin catheter tube with a small reservoir at the end that sits on top of the skull under the scalp. The work continues at Duke, where Ravi Bellamkonda, who began the research while at Georgia Tech, is now Vinik Dean of the Pratt School.

“This was the first demonstration that you can engineer migration inside the body and move a tumor from point A to point B by design,” said Bellamkonda in a statement from Duke. “It was also the first demonstration of bringing the tumor to your drug rather than your drug going into the brain and killing valuable cells.”

“What’s most important is that the tumor is spreading in a controlled way through our device to a reservoir, and away from the mother tumor, rather than through the healthy brain tissue,” added project leader Nassir Mokarram, a research faculty member at Duke’s Department of Biomedical Engineering. “The toxic gel inside the reservoir appears to only play a secondary role, though additional preclinical studies will help make this clear. Simply by being far away from the mother tumor, the cells are more susceptible to dying anyway, and a neurosurgeon can access the reservoir to empty it when needed.”

Breakthrough designations from the FDA aim to expedite the development and review of drugs, diagnostics and devices aimed at life-threatening or irreversibly debilitating conditions. While the designation does not mean that the device has been approved for clinical use, it does provide a partnership with the FDA that can speed development, assessment, and review.

“The tumor monorail device is a true game-changer in how we think about treating brain tumors,” said Barun Brahma, a neurosurgeon at Children’s Healthcare of Atlanta, also a member of the research team since the beginning. “There are many tumors that are considered inoperable due to the location of the tumor or the frailty of the patient. This device affords clinicians the ability to surgically treat these tumors with a minimal approach.”

Since the initial study, the results in rats have been successfully reproduced multiple times by the research group. The researchers are working toward gaining FDA approval for human trials by the end of 2019.

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