Preclinical studies of a death receptor 5 fusion protein that ameliorates acute liver failure

J Mol Med (Berl). 2019 Sep;97(9):1247-1261. doi: 10.1007/s00109-019-01813-w. Epub 2019 Jun 22.

Abstract

Acute liver failure (ALF) is a life-threatening disease with a high mortality rate. There is an urgent need to develop new drugs with high efficacy and low toxicity. In this study, we produced a pharmaceutical-grade soluble death receptor 5 (sDR5)-Fc fusion protein for treating ALF and evaluated the pharmacology, safety, pharmacokinetics, efficacy, and mechanisms of sDR5-Fc in mice, rats, and cynomolgus monkeys. sDR5-Fc bound with high affinity to both human and monkey tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) effectively blocked TRAIL-induced apoptosis in vitro and significantly ameliorated ALF induced by concanavalin A (Con A) in mice. Mechanistically, sDR5-Fc inhibited hepatocyte death and reduced inflammation in vivo. Furthermore, sDR5-Fc attenuated the production of inflammatory cytokines by splenocytes activated with Con A or an anti-CD3 antibody in vitro. Consistent with these results, splenocytes from TRAIL-/- mice produced much lower levels of inflammatory cytokines than those from TRAIL+/+ mice. In cynomolgus monkeys, sDR5-Fc was safe and well tolerated when intravenously administered as a single dose of up to 1200 mg/kg or multiple doses of 100 mg/kg. After treatment with a single dose, linear pharmacokinetics with a mean half-life of > 1.9 days were observed. After 12 weekly doses, sDR5-Fc exposure increased in an approximately dose-proportional manner, and the mean accumulation ratio ranged from 1.82- to 2.11-fold. These results support further clinical development of our sDR5-Fc protein as the first TRAIL-targeting drug for ALF treatment. KEY MESSAGES: sDR5-Fc binds with high affinity to TRAIL to effectively block TRAIL-induced apoptosis. sDR5-Fc ameliorates Con A-induced acute liver failure in mice by inhibiting hepatocyte death and inflammation. sDR5-Fc or TRAIL knockout attenuates the production of inflammatory cytokines by activated splenocytes in vitro. sDR5-Fc is safe and well tolerated in acute or long-term toxicity study.

Keywords: Acute liver failure; Apoptosis; Death receptor; Inflammation; TRAIL.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Apoptosis / physiology
  • Apoptosis Regulatory Proteins / metabolism
  • Cell Line, Tumor
  • Concanavalin A / metabolism
  • Cytokines / metabolism
  • Hep G2 Cells
  • Humans
  • Inflammation / metabolism
  • Liver Failure, Acute / metabolism*
  • Macaca fascicularis
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Rats
  • Rats, Sprague-Dawley
  • Receptors, TNF-Related Apoptosis-Inducing Ligand / metabolism*
  • TNF-Related Apoptosis-Inducing Ligand / metabolism

Substances

  • Apoptosis Regulatory Proteins
  • Cytokines
  • Receptors, TNF-Related Apoptosis-Inducing Ligand
  • TNF-Related Apoptosis-Inducing Ligand
  • TNFRSF10B protein, human
  • Concanavalin A