R&D initiatives are initially focus on the use of XENEX™ as a neuroprotectant in post-cardiac arrest syndrome (PCAS) patients. 

Following a successful in-hospital PCAS study, the focus will move to PCAS in a pre-hospital ambulance setting.  This opens the door to future indications in therapeutic areas such as stroke and traumatic brain injury.

XENEX™ for Post Cardiac Arrest Syndrome

Post-Cardiac Arrest Syndrome (PCAS) Background

Cardiac arrest (CA), which is an abrupt loss of heart function related to the body’s electrical system, is often precipitated by a heart attack, which is related to blood flow blockage.  Loss of blood-flow and oxygenation to the brain, known as hypoxia-ischemia, causes neurologic damage and often results in death.  In fact, an estimated 75% of all CA deaths are attributed to brain injury.

With over 500,000 patients per year in the United States alone, CA is the 3rd leading cause of death with approximately one CA occurring every minute.  The majority of the CA events occur outside of the hospital, and only an estimated 60% of the patients are alive to be treated by emergency medical responders.  Of those fortunate enough to be resuscitated, only about 1/3 survive to hospital discharge.


There is currently no pharmacotherapy available for neuroprotection in the resuscitated PCAS patient population, i.e. those who experience a return of circulation but remain comatose. The current standard of care, upon diagnosis and any intervention, is targeted temperature management (TTM), also known as therapeutic hypothermia, administered for 24 hours in the critical care setting. Even with mounting evidence and wide spread adoption of TTM, only about 50% of PCAS patients who receive therapy survive to discharge. Reperfusion injury is the leading cause of death in this setting.


Extensive preclinical findings suggest that xenon is a promising neuroprotective therapy in hypoxic-ischemic patients, especially when administered with TTM. The positive results of a Phase II Study (N=110) in out-of-hospital cardiac arrest (OHCA) support these findings.  NPXE hopes to replicate these findings in the larger Phase III XePOHCAS Trial.

Phase III XePOHCAS Trial

Xenon for Neuroprotection During Post-Cardiac Arrest Syndrome in Comatose Survivors of an Out of Hospital Cardiac Arrest (XePOHCAS)

TRIAL DESIGN: Randomized, controlled trial of ~1,400 patients in ~30 centers in North America and Europe

PATIENT POPULATION: Adult patients who benefited the most in Phase II study – return of spontaneous circulation (ROSC) within 30 minutes

TREATMENT ARMS: XENEX™ plus Targeted Temperature Management (TTM) versus TTM-Alone

PRIMARY ENDPOINTS:  Survival & Good Neurological Outcome (able to manage own affairs without assistance)

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Pre-Hospital OHCA

The general held belief is that “time is brain.”  Upon completion of a successful Phase III XePOHCAS Trial, which studied the administration of xenon in the intermediate care unit (ICU), NPXe plans to evaluate xenon administration in an ambulance setting.

Xenon Delivery System

Hospital Delivery Device

The Xenon Delivery System (XDS) delivers XENEX™ into a patented closed-loop inhalation system consisting of a proprietary gas controller, consumable circuit, ventilator, and a patient monitor.

Pre-Hospital Delivery Device

NPXe plans to develop a pre-hospital XDS to prosecute studying xenon in the ambulance setting.