Design and Mechanistic Analysis of a Potent Bivalent Inhibitor of Transthyretin Amyloid Fibrillogenesis

J Med Chem. 2025 Jun 12;68(11):11543-11571. doi: 10.1021/acs.jmedchem.5c00430. Epub 2025 May 27.

Abstract

Transthyretin amyloidosis (ATTR) is a systemic disease that primarily affects the heart and the peripheral nervous system. Despite available therapeutic options, advanced ATTR amyloidosis still presents unmet medical needs. We have therefore focused on the design of bivalent small molecules starting from our prototype palindromic ligand mds84, whose binding by transthyretin (TTR) greatly improves stability of the native structure by overcoming the negative cooperativity which is typical of monovalent stabilizers. Among the newly designed compounds here, we present B26, which is pseudoirreversibly bound by native TTR with faster entry kinetics into the protein molecule compared to mds84. It retains the ability to inhibit fibril formation in vitro, together with improved solubility. Using solution NMR, we show that B26 occupies both TTR binding sites simultaneously, leading to conformational effects distant from the binding site, including the proteolytic cleavage site involved in fibril formation by the mechano-enzymatic mechanism.

MeSH terms

  • Amyloid Neuropathies, Familial / drug therapy
  • Amyloid* / antagonists & inhibitors
  • Amyloid* / chemistry
  • Amyloid* / metabolism
  • Binding Sites
  • Drug Design*
  • Humans
  • Ligands
  • Prealbumin* / antagonists & inhibitors
  • Prealbumin* / chemistry
  • Prealbumin* / metabolism

Substances

  • Prealbumin
  • Amyloid
  • Ligands

Supplementary concepts

  • Amyloidosis, Hereditary, Transthyretin-Related