Comprehensive Report on KN-057 (Armocibart): A Novel TFPI-Inhibiting Monoclonal Antibody for Hemophilia

Executive Summary

KN-057, also known under the proposed International Nonproprietary Name (INN) Armocibart, is an investigational monoclonal antibody developed by Suzhou Alphamab Biotechnology Co., Ltd. It functions by inhibiting Tissue Factor Pathway Inhibitor (TFPI), a natural anticoagulant, thereby promoting coagulation.[1] This mechanism is particularly relevant for treating hemophilia A and B, including patients who have developed inhibitors to standard factor replacement therapies, as the action of KN-057 is independent of the deficient or inhibited clotting factors VIII or IX.[3] Currently, KN-057 is advancing through late-stage clinical development, with multiple Phase 3 trials underway in China and a Phase 2 trial completed.[1] Administered subcutaneously, early clinical data suggests a favorable safety profile, a pharmacokinetic profile supporting once-weekly dosing, and positive pharmacodynamic effects on thrombin generation.[5] Highlighting its potential to address a significant unmet medical need, KN-057 has received Orphan Drug Designation from the U.S. Food and Drug Administration (FDA) for hemophilia A.[2] This report synthesizes available preclinical rationale, clinical trial details, pharmacokinetic and pharmacodynamic profiles, safety information, regulatory status, and intellectual property pertaining to KN-057.