Phase 2a Immune Modulation With Ultrasound for Newly Diagnosed Glioblastoma

Brain tumor treatment is hampered by the blood-brain barrier (BBB). This barrier prevents drugs carried in the bloodstream from getting into the brain. If the BBB can be opened, making it temporarily more permeable, drugs may able to better reach the brain tumor. In this trial we will implant a novel device with 9 ultrasound emitters, allowing temporary and reversible opening of the BBB to maximize brain penetration of drugs that modulate the immune system. The device will be implanted after radiation is completed. Immune modulating drugs will be given every 3 weeks in conjunction with activation of the device to open the BBB. The objectives of this trial are to establish whether it is safe and feasible to administer immune modulating drugs in this manner, and identify whether the treatment is effective in treating glioblastoma.

Eligible patients will undergo implant of the Soncloud-9 device within 1-5 weeks of completion of radiotherapy. About 1-3 weeks after surgery, patients will undergo sonication and intravenous administration of balstilimab, botensilimab and liposomal doxorubicin. Brain MRI will be done to quantify extent of blood brain barrier opening. The dose for balstilimab is 450 mg every 3 weeks. The dose for botensilimab is 1mg/kg every 6 weeks. The dose for liposomal doxorubicin is 30 mg every 3 weeks. Sonication and administration of study agents will continue every 3 weeks (21 days= 1 cycle) for a total of 9 cycles (approx. 6 months). Additional cycles may be considered if deemed beneficial and in the patient's best interest. Blood samples for circulating tumor DNA will also be collected before and after each sonication. The first 6 patients will comprise a safety run-in cohort with intensified safety monitoring through the end of the second cycle.