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Pediatric Brain Cancer

The second most common type of cancer in children.

Pediatric brain cancers (PBCs), such as high-grade glioma and ependymoma, are malignant tumors in the brain or spinal cord that account for approximately 26% of all childhood cancers.

High-Grade Glioma (HGG)

About

HGG is a rare, fast-growing CNS tumor that forms in glial cells of the brain and spinal cord. It can be found almost anywhere within the CNS, but is most commonly within the supratentorium in children ages 15-19. HGG tumors in children act differently from those in adults, causing headaches, seizures, and difficulty achieving developmental milestones depending on the tumor location.

Incidence

360-400

children diagnosed each year in North America

Survival

20%

of children survive 5 years from diagnosis

Current Treatment Approaches

As HGG spreads quickly through brain tissue, it is difficult to treat. The tumor’s location and a microscopic evaluation of the grade (grade III anaplastic astrocytoma and grade IV glioblastoma) helps determine the progression of the disease and the best potential treatments.
The standard of care accepted by most experts is to attempt a complete surgical resection followed by a combination of focal radiotherapy and chemotherapy in children over 3 years of age. If tumor recurrence follows chemotherapy and radiation, experimental treatments may be considered.

Ependymoma

About

Ependymoma is a rare, slow- or fast-growing (depending on the grade) primary CNS tumor that forms in ependymal cells in the brain and spinal cord – and may spread throughout the CNS, though infrequently. All ependymomas can recur, but patients are often tumor-free for years before testing shows tumor regrowth, either at the initial tumor site or elsewhere within the CNS. Symptoms depend on tumor location and size, usually including irritability, sleeplessness, vomiting, nausea, back pain, arm/leg weakness, and headaches.

Incidence

250

children diagnosed each year in the U.S.

Survival

71%

of children with Grade II and 57% with Grade III survive 5 years from diagnosis

Current Treatment Approaches

Treatment involves a combination of surgery, radiation therapy, and/or chemotherapy. Once the tumor is removed, patients are often administered radiation therapy, though many are only able to receive a single dose.
The role of chemotherapy is unclear, but it may be used for recurrent tumors following radiation therapy or to delay radiation in infants and very young children.

The Opportunity

To develop a minimally invasive procedure
that can more safely deliver a high dose of
radiation directly to a child’s CNS tumor.

Compared to similar radiotherapeutics, rhenium (186Re) obisbemeda may potentially clear the body in a quicker amount of time – less than a day. The use of the radioisotope, Rhenium-186, also appears to be a better match for this application than other radioisotopes, as it has a 3.8-day half-life that facilitates higher dose amounts to be absorbed in the CNS before entering the circulatory system.
Our lead drug candidate, rhenium (186Re) obisbemeda, is a radiotherapeutic designed to inject high doses of radiation directly into the CNS via Convection Enhanced Delivery (CED). By targeting the tumor more precisely, we expect 186RNL will minimize radiation exposure to normal tissues, exhibit a higher safety margin and bypass the blood-brain barrier more effectively than EBRT.
The ReSPECT-PBC Phase 1 clinical trial evaluating rhenium (186Re) obisbemeda for the treatment of recurrent, refractory, or progressive pediatric ependymoma or high-grade glioma is expected to start in 2023.