Nasal Spray Developed to Protect Brain Cells Immediately After Stroke

Scientists in Hong Kong have developed a nasal spray designed to protect brain cells immediately after a stroke occurs. The spray uses ultra-small inhalable powders containing brain-protective drugs that are inhaled into the nasal cavity. These powders separate into nanoparticles that travel along the nose-to-brain pathway, delivering the drug directly to the brain while bypassing the blood-brain barrier.

Stroke remains one of the leading causes of death and disability worldwide. It imposes an annual economic burden exceeding $890 billion on healthcare systems. Existing treatments, which include clot-breaking drugs and therapies to restore blood flow, can begin only after a patient reaches a hospital.

More than 85 percent of patients cannot receive these interventions in time because the window for effective treatment is narrow. Many drug candidates targeting the central nervous system fail in clinical trials because they cannot cross the blood-brain barrier.

The failure rate of such drug candidates exceeds 90 percent, largely because the drugs cannot reach the brain to exert therapeutic effects. The new nasal spray is intended to provide protection while patients are en route to medical facilities. Tests showed that administering the spray within 30 minutes of stroke onset reduced brain tissue death by over 80 percent.

It also helped preserve neurological functions and body movement. The spray mitigates inflammation, prevents cell death and maintains the integrity of the blood-brain barrier. This approach could extend the time available for subsequent hospital-based treatments.

Researchers described the spray as a potential breakthrough for prehospital emergency care. "After a stroke, every second matters," a postdoctoral fellow at Hong Kong University said. " The technology shifts the focus of stroke treatment from the in-hospital setting to the prehospital stage.

It emphasizes neuroprotection in addition to clot dissolution or mechanical clot removal.

The nasal spray, referred to as Nanopowder, was created by researchers at Hong Kong University. It deposits in the target area of the nasal cavity and converts into nanoparticles that follow a direct pathway to the brain. This delivery method avoids the limitations that prevent many intravenous drugs from reaching affected brain tissue.

Current standard care begins after hospital admission. The spray is designed to slow brain cell death during transport, buying time for definitive treatments once the patient arrives.