Amunix announces report by Bioverativ on unprecedented half-life obtained in patients treated with a novel, long-acting FVIII utilizing Amunix’s XTEN® technology

MOUNTAIN VIEW, Calif., May 29, 2018 (GLOBE NEWSWIRE) – Amunix Operating Inc. is pleased to report that Bioverativ (a Sanofi company) has announced preliminary Phase 1/2a safety and pharmacokinetic clinical data for BIVV001 (rFVIIIFc-VWF-XTEN), a novel and investigational factor VIII therapy for people with hemophilia A that incorporates Amunix’s XTEN technology to improve circulatory half-life.  In previous announcements, Bioverativ had noted that BIVV001 is the only investigational factor VIII therapy in development that has been specifically designed to overcome the von Willebrand factor ceiling, which is believed to impose a half-life limitation on current factor VIII therapies. Data from the ongoing EXTEN-A clinical study showed that a single low dose of BIVV001 extended the half-life of factor VIII to an unprecedented 37 hours, with high factor activity levels, and was generally well-tolerated. The data were presented at the World Federation of Hemophilia (WFH) 2018 World Congress (Glasgow, Scotland).

“We are delighted to see such a fundamental clinical breakthrough based on the ground-breaking efforts of the many scientists at Bioverativ and Amunix,” stated Volker Schellenberger, CEO and President of Amunix. “We view this news as a potentially transformative milestone for the treatment of hemophilia A patients. For Amunix, this represents further validation of our XTEN technology platform to improve the pharmacokinetics of therapeutic payloads and enhance their delivery.”

In its announcement, Bioverativ indicated that it is now planning to explore twice-a-month dosing with BIVV001, which could transform the treatment paradigm in people with hemophilia A.

About Amunix:

Amunix, based in Mountain View, CA, is a privately held biotechnology company with two proprietary technologies, XTEN and ProTIA, for the discovery and development of novel therapeutics.  Amunix collaborative partners have included Celgene, Genentech, Janssen, Roche, Bioverativ, Baxter, Ambrx, Zealand, Noxxon, and other undisclosed partners in a wide range of therapeutic areas. 

XTEN is a half-life extension technology based on hydrophilic, unstructured, biodegradable proteins that impart a number of favorable properties upon the molecules to which they are attached. In addition to the advantages of reduced dosing frequency, XTENylation stabilizes plasma drug concentrations, which often results in increased efficacy as well as reduced side effects. Amunix has licensed this technology to numerous companies in a wide range of therapeutic areas. Three genetically-fused XTENylated products have been clinically tested.

Amunix is internally developing a pipeline of investigational antibody therapeutics based on its ProTIA (Protease Triggered Immune Activator) technology platform, as well as offering partners access to the technology for augmenting the safety and efficacy of their antibody and cytokine-based proprietary molecules. ProTIA are bispecific immuno-oncologics administered as long-acting prodrugs that can be activated in the tumor environment by tumor-associated proteases, resulting in the binding of T cells to highly-expressed tumor antigens triggering the destruction of the cancer cell.  Due to the selective and localized activation, ProTIA are expected to have an improved safety profile over conventional immuno-oncologics.

For additional information about the company, please visit

Volker Schellenberger, Ph.D.
President and CEO
Tel: 650-889-5095