KG207

KG207 is a bi-functional engineered biologic being developed for Alzheimer’s disease that consists of a blood–brain barrier–penetrant single-domain antibody (FC5) fused via an IgG Fc fragment to an amyloid‑β oligomer‑binding peptide, enabling active transport into the brain and selective clearance of highly toxic soluble Aβ42 oligomers.[1][4][8][9][11] Designed as a modified IgG1-Fc fusion protein of approximately 90 kDa rather than a conventional monoclonal antibody, it incorporates an Fc5-mediated transcytosis motif for >10‑fold higher brain exposure than standard mAbs, point mutations in the Fc region (C220S, D270G) to attenuate pro‑inflammatory Fcγ receptor interactions, and an oligomer‑specific binding peptide to promote removal of toxic Aβ via cerebrospinal fluid while sparing plaque and monomeric forms and reducing ARIA‑E/H risk.[1][4][8][9] In transgenic rodent models, KG207 (and the closely related construct KG207‑M/FC5‑mFc2a‑ABP) reduced brain amyloid load by PET, increased CSF Aβ42/40 ratio, improved functional connectivity and hippocampal volume, normalized CSF neurofilament light chain, and showed no evidence of amyloid‑related imaging abnormalities or microhemorrhage, supporting its development as a disease‑modifying therapy for early Alzheimer’s disease.[1][2][4][5][9][11]

Other names

FC5-mFc2a-ABPFC-5-mFc2a-ABPFC 5-mFc2a-ABPFC5-mFc-ABPFC-5-mFc-ABPFC 5-mFc-ABPFC5-mFc2a-ABP fusion proteinFC-5-mFc2a-ABP fusion proteinFC 5-mFc2a-ABP fusion protein