Science of Coagulation

Blood coagulation is an important part of the host defense mechanism required for repair and maintenance of the circulatory system. This complex and multifactorial process has been described to contain two parallel but distinct pathways; hemostasis and thrombosis.

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Why Factor XIa?

Factor XIa is a clinically-validated target for the prevention of thrombosis by selectively inhibiting the activation of the intrinsic (contact) pathway, without impacting normal hemostasis (bleeding) through the extrinsic pathway.

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About Frunexian

  • eXIthera’s lead IV candidate Frunexian (formerly EP-7041) is a novel, potent and selective small-molecule Factor XIa inhibitor
  • Completed Phase 1 demonstrating safety, tolerability and ideal clinical PK profile with validated efficacy marker aPTT
  • Established that effective anticoagulation is achievable with a small molecule therapeutic without the danger of increased bleeding risk or the need for a reversal agent
  • Preventing major bleeding events saves lives and will significantly reduce healthcare costs


Westborough, Mass., March 3, 2021 – eXIthera Pharmaceuticals, a clinical-stage biotechnology company focused on addressing bleeding complications associated with currently available antithrombotic agents through the targeted inhibition of coagulation Factor XIa, today announced the U.S. Food and Drug Administration (FDA) has accepted its Investigational New Drug (IND) application to initiate a Phase 2 clinical trial […]
Dr. Neil Hayward, CEO and founder of eXlthera, is here to discuss his company, which is developing Factor XI inhibitor antithrombotics that are attacking blood clots from a new angle and are giving patients new hope.