Discovery of Roblitinib (FGF401) as a Reversible-Covalent Inhibitor of the Kinase Activity of Fibroblast Growth Factor Receptor 4

J Med Chem. 2020 Nov 12;63(21):12542-12573. doi: 10.1021/acs.jmedchem.0c01019. Epub 2020 Oct 1.

Abstract

FGF19 signaling through the FGFR4/β-klotho receptor complex has been shown to be a key driver of growth and survival in a subset of hepatocellular carcinomas, making selective FGFR4 inhibition an attractive treatment opportunity. A kinome-wide sequence alignment highlighted a poorly conserved cysteine residue within the FGFR4 ATP-binding site at position 552, two positions beyond the gate-keeper residue. Several strategies for targeting this cysteine to identify FGFR4 selective inhibitor starting points are summarized which made use of both rational and unbiased screening approaches. The optimization of a 2-formylquinoline amide hit series is described in which the aldehyde makes a hemithioacetal reversible-covalent interaction with cysteine 552. Key challenges addressed during the optimization are improving the FGFR4 potency, metabolic stability, and solubility leading ultimately to the highly selective first-in-class clinical candidate roblitinib.

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Binding Sites
  • Cell Line, Tumor
  • Cell Proliferation / drug effects
  • Cysteine / chemistry
  • Dogs
  • Drug Design
  • Half-Life
  • Hepatocytes / cytology
  • Hepatocytes / drug effects
  • Hepatocytes / metabolism
  • Liver Neoplasms / drug therapy
  • Mice
  • Microsomes, Liver / metabolism
  • Molecular Dynamics Simulation
  • Piperazines / chemistry*
  • Piperazines / metabolism
  • Piperazines / pharmacology
  • Piperazines / therapeutic use
  • Protein Kinase Inhibitors / chemistry*
  • Protein Kinase Inhibitors / metabolism
  • Protein Kinase Inhibitors / pharmacology
  • Protein Kinase Inhibitors / therapeutic use
  • Pyridines / chemistry*
  • Pyridines / metabolism
  • Pyridines / pharmacology
  • Pyridines / therapeutic use
  • Rats
  • Receptor, Fibroblast Growth Factor, Type 4 / antagonists & inhibitors*
  • Receptor, Fibroblast Growth Factor, Type 4 / metabolism
  • Structure-Activity Relationship
  • Xenograft Model Antitumor Assays

Substances

  • Piperazines
  • Protein Kinase Inhibitors
  • Pyridines
  • Receptor, Fibroblast Growth Factor, Type 4
  • Cysteine
  • roblitinib