FDA Approves Study for Next-Generation TherOx SSO2 Therapy for AMI

November 5, 2015—TherOx, Inc. announced it has received US Food and Drug Administration (FDA) investigational device exemption approval for a confirmatory safety study of a second-generation system that delivers supersaturated oxygen (SSO₂) therapy for reduction of infarct size after an acute myocardial infarction (AMI). This 100-patient study is being conducted to support a premarket approval submission to the FDA. 

According to TherOx, SSO₂ therapy is intended as the first treatment option beyond percutaneous coronary intervention (PCI) to salvage heart muscle in AMI patients. It is a solution of highly oxygenated saline mixed with the patient’s blood, delivered through a catheter to the targeted ischemic area of the heart. SSO₂ therapy, adjunctive to PCI, is intended to salvage the jeopardized myocardium and thus reduce infarct size.
    
Simon Dixon, MBChB, an investigator for this study, commented in the company’s announcement, “In multiple peer-reviewed studies, we have found the infarct size reduction achieved by SSO₂ therapy was clinically significant compared to PCI. I am excited about the potential that SSO₂ therapy shows in improving outcomes for patients experiencing large anterior infarcts and treated within 6 hours of onset.” Dr. Dixon is chair of cardiovascular medicine at Beaumont Hospital in Royal Oak, Michigan.
 
The first-generation TherOx SSO₂ therapy received European CE Mark approval and was successful in meeting the safety and effectiveness endpoints in the AMIHOT II trial. Statistical results from the AMIHOT II trial of SSO₂ therapy, together with PCI and stenting, demonstrated a 26% relative reduction in infarct size compared to PCI and stenting alone.
 
The company advised that this second-generation system builds on the success of AMIHOT II and includes the additional benefits of shortening the treatment time to 60 minutes and expanding the myocardial treatment area to the entire left coronary system so that no ischemic area goes untreated. SSO₂ therapy supports the current guidelines for interventional cardiology procedures, noted TherOx.

In the United States, SSO₂ therapy is delivered by an investigational device and is limited by United States law to investigational use. It is not for sale or distribution in the United States.