Asahi Kasei company Zoll Medical has secured an investigational device exemption (IDE) approval from the US Food and Drug Administration (FDA) to begin the feasibility study of TherOx Supersaturated Oxygen (SSO2) Therapy.

The randomised and prospective ISO SHOCK study will assess the use of TherOx SSO2 Therapy in patients with ST Elevation Myocardial Infarction (STEMI) and cardiogenic shock and treated concurrently with a mechanical circulatory support device.

The trial will allow the company to evaluate the safety and feasibility of delivering SSO2 Therapy to patients presenting with STEMI and cardiogenic shock compared to standard practice and outcomes shown in the National Cardiogenic Shock Initiative (NCSI).

Zoll Circulation president Neil Johnston said: “SSO2 Therapy was designed to recover damaged myocardium in heart attack patients, with the intention of preventing devastating heart failure and potentially death.

“The initiation of the ISO SHOCK trial for the sickest of these patients — those in cardiogenic shock — only reinforces our commitment to this cause.”

A STEMI heart attack is related to a two-fold increased risk of developing cardiogenic shock, a condition in which the heart cannot pump adequate oxygenated blood to important organs.

SSO2 Therapy is expected to hold the potential to mitigate damaged tissue while enhancing left ventricular structure and function in this complex patient population.

Zoll Medical will randomise 60 patients in the study in 20 sites across the US to evaluate whether SSO2 Therapy could deliver benefit to patients compared to the current standard of care.

The trial’s primary safety endpoint will evaluate mortality at 30 days with the SSO2 Therapy group compared to the control group as well as against the historical 32% mortality from the NCSI.

In addition, the feasibility endpoints will measure completion of a 60-minute SSO2 infusion after successful PCI and securing an MRI between three and seven days after PCI.

SSO2 Therapy is claimed to be the first and only FDA-approved treatment to significantly minimise cardiac muscle damage in heart attack patients after percutaneous coronary intervention.

California-based TherOx, which is now part of Zoll Medical, has developed SSO2 Therapy.