Discovery of BIO-8169─A Highly Potent, Selective, and Brain-Penetrant IRAK4 Inhibitor for the Treatment of Neuroinflammation

J Med Chem. 2024 May 23;67(10):8383-8395. doi: 10.1021/acs.jmedchem.4c00560. Epub 2024 May 2.

Abstract

Interleukin receptor associated kinase 4 (IRAK4) plays an important role in innate immune signaling through Toll-like and interleukin-1 receptors and represents an attractive target for the treatment of inflammatory diseases and cancer. We previously reported the development of a potent, selective, and brain-penetrant imidazopyrimidine series of IRAK4 inhibitors. However, lead molecule BIO-7488 (1) suffered from low solubility which led to variable PK, compound accumulation, and poor in vivo tolerability. Herein, we describe the discovery of a series of pyridone analogs with improved solubility which are highly potent, selective and demonstrate desirable PK profiles including good oral bioavailability and excellent brain penetration. BIO-8169 (2) reduced the in vivo production of pro-inflammatory cytokines, was well tolerated in safety studies in rodents and dog at margins well above the predicted efficacious exposure and showed promising results in a mouse model for multiple sclerosis.

MeSH terms

  • Animals
  • Brain* / drug effects
  • Brain* / metabolism
  • Dogs
  • Drug Discovery
  • Encephalomyelitis, Autoimmune, Experimental / drug therapy
  • Interleukin-1 Receptor-Associated Kinases* / antagonists & inhibitors
  • Interleukin-1 Receptor-Associated Kinases* / metabolism
  • Male
  • Mice
  • Neuroinflammatory Diseases / drug therapy
  • Neuroinflammatory Diseases / metabolism
  • Protein Kinase Inhibitors* / chemical synthesis
  • Protein Kinase Inhibitors* / chemistry
  • Protein Kinase Inhibitors* / pharmacokinetics
  • Protein Kinase Inhibitors* / pharmacology
  • Protein Kinase Inhibitors* / therapeutic use
  • Pyrimidines / chemical synthesis
  • Pyrimidines / chemistry
  • Pyrimidines / pharmacokinetics
  • Pyrimidines / pharmacology
  • Pyrimidines / therapeutic use
  • Rats
  • Structure-Activity Relationship

Substances

  • Interleukin-1 Receptor-Associated Kinases
  • IRAK4 protein, human
  • Protein Kinase Inhibitors
  • Pyrimidines