Scientists in Hong Kong have developed the world’s first nasal spray to protect brain cells immediately following a stroke, an advance they claim could lead to a new “emergency rescue tool”.
Stroke is one of the leading causes of death and disability, imposing an annual burden exceeding $890bn on healthcare systems worldwide.
Current treatment for stroke begins after hospital admission and involves the use of clot-breaking drugs and reperfusion therapies designed to restore blood flow through arteries going to the brain.
As the window for effective intervention is extremely narrow, however, more than 85 per cent of the patients are unable to receive timely treatment.
Many drugs targeting the brain in clinical trials also fail as they cannot cross the organ’s protective barrier to keep away infectious germs from the blood.
So developing timely interventions that are effective and safe within the “golden therapeutic window” remains key.
“The failure rate of drug candidates targeting the central nervous system in clinical trials exceeds 90 per cent, largely because these drugs cannot cross the blood-brain barrier, and thus fail to reach the brain to exert their therapeutic effects,” Aviva Chow Shing-fung from Hong Kong University explained.
To overcome this, scientists developed the “Nanopowder” nasal spray with brain-protective drugs as the active ingredient, developed into ultra-small inhalable powders.
The spray is inhaled into the nasal cavity, where it effectively deposits in the target area and separates into nanoparticles.
The tiny particles then travel along the nose-to-brain pathway, bypassing the blood-brain barrier to deliver the drug directly to the organ, researchers say.
The nasal spray provides early protection en route to the hospital, significantly slowing the death of brain cells immediately after a stroke and buys valuable time for subsequent intervention, scientists say, adding that it can be a breakthrough solution for prehospital emergency treatment of stroke.
Researchers found that administering the nasal spray within 30 minutes of stroke onset could reduce the death of brain tissues by over 80 per cent and protect neurological and body movement functions.
The spray can mitigate inflammation, prevent cell death and preserve the integrity of the blood-brain barrier, potentially extending the time available for treatment, they say.
“After a stroke, every second matters,” Shao Zitong, a post doctoral fellow at Hong Kong University said.
“Even an additional 10 minutes of brain protection might determine whether a patient can walk or speak in the future.”
“The key breakthrough of this technology lies in shifting stroke treatment from the ‘in-hospital’ setting to the ‘prehospital’ stage,” she explained, “enabling neuroprotection rather than merely clot dissolution or thrombectomy.”