The Story of Endexo Anti-Thrombotic Polymer Additives from Interface Biologics

One of the greatest challenges for implanted medical devices is to overcome the body’s own defense systems. Unfortunately, the immune system treats all foreign materials as threats, including medical implants whose purpose is to restore health or prolong life.

Interface Biologics Inc (IBI) is a Canada-based company that develops transformative biomedical polymer technology with the purpose of improving the safety and effectiveness of medical devices, addressing the body’s own defense system. It all started back in December 2001 at the University of Toronto in Dr Paul Santerre’s lab, with his groundbreaking work on materials for improving the biocompatibility of medical implants. Seed financing was raised from venture capital funds to demonstrate proof-of-concept of the now trademarked Endexo technology for providing anti-thrombotic character in a variety of polyurethane chemistry applications such as catheters, blood bags, stent grafts and other blood contacting devices.  

The Endexo technology encompasses a range of low molecular weight additives for reduced thrombus formation on devices without the use of heparin. It was expanded to a wide-range of polymers including many medical grade plastics with different hardness, processing temperatures and processing means (for example, injection molding, solution spinning or extrusion)

In 2005, post Series A financing, Interface Biologics moved into the Toronto’s acclaimed MaRS Innovation Centre, a collaborative facility dedicated to accelerating emerging technologies.  This is located near the University of Toronto campus and is close to seven specialty hospitals.  Working within their newly built state-of-the-art lab facilities, IBI began working with a wide variety of catheter manufacturers to better understand the implementation of the Endexo technology in a specific application.

Endexo is a low molecular weight polymer with a range of chemistries. IBI has numerous different formulations depending on the application and base polymer requirements. The chemistry make-up allows the molecules to migrate to the top nanometers of material interface, such that it is present on all surfaces. The additive is typically added at 1-5 weight percent and provides significant surface modification.

The Endexo technology provides a passive surface that reduces adhesion and activation of blood proteins and components, thereby reducing thrombus formation. This feature is useful in vascular access catheters where thrombus formation can lead to deep vein thrombosis and subsequent downstream emboli, resulting in high morbidity and mortality.

Endexo technology is currently licensed to AngioDynamics for vascular access devices and Fresenius Medical Care for chronic dialysis systems. The AngioDynamics BioFlo PICC and BioFlo Port (both trademarked) are the first ever anti-thrombogenic catheters to gain FDA clearance. In-vitro blood loop results show that on average the BioFlo Port catheter had 96% less thrombus accumulation on its surface compared to non-coated conventional port catheters.

In addition to Endexo technology, IBI has a rich pipeline of biomedical polymers that enable devices to deliver pharmaceuticals, small molecules, peptides and biologics. The next generation products take advantage of the simplicity of various chemistries and self-locating properties to proactively engage biological systems for drug delivery applications. 

More than a decade later, Dr Paul Santerre remains actively involved as chief scientific officer at Interface Biologics. In this role, he works with IBI employees, scientific advisors and industry partners to help move their innovative ideas from a polymer chemistry lab to clinical applications, ultimately improving patient outcomes and reducing costs for the healthcare system.