A randomized, placebo-controlled trial of emricasan in patients with NASH and F1-F3 fibrosis.

BACKGROUND & AIMS: Non-alcoholic steatohepatitis (NASH) is characterized by hepatocyte steatosis, ballooning, and lobular inflammation which may lead to fibrosis. Lipotoxicity activates caspases, which cause apoptosis and inflammatory cytokine (IL-1ß and IL-18) production. Emricasan is a pan-caspase inhibitor that decreases serum aminotransferases and caspase activation in patients with NASH. This study postulated that 72 weeks of emricasan treatment would improve liver fibrosis without worsening of NASH. METHODS: In this double-blind, placebo-controlled study 318 patients were randomized 1:1:1 to twice-daily treatment with emricasan (5 mg or 50 mg) or matching placebo for 72 weeks. Patients had definite NASH and NASH CRN fibrosis stage F1-F3, as determined by a central reader, on a liver biopsy obtained within 6 months of randomization. RESULTS: Emricasan treatment did not achieve the primary objective of fibrosis improvement without worsening of NASH (emricasan 5 mg: 11.2%; emricasan 50 mg: 12.3%; placebo: 19.0%; odds ratios vs. placebo 0.530 and 0.588, with p = 0.972 and 0.972, respectively) or the secondary objective of NASH resolution without worsening of fibrosis (emricasan 5 mg: 3.7%; emricasan 50 mg: 6.6%; placebo: 10.5%; odds ratios vs. placebo 0.334 and 0.613, with p = 0.070 and 0.335, respectively). In the small subset of patients with consistent normalization of serum alanine aminotransferase over 72 weeks, emricasan may have improved histologic outcomes. CONCLUSIONS: Emricasan treatment did not improve liver histology in patients with NASH fibrosis despite target engagement and may have worsened fibrosis and ballooning. Caspase inhibition lowered serum alanine aminotransferase in the short-term but may have directed cells to alternative mechanisms of cell death, resulting in more liver fibrosis and hepatocyte ballooning. CLINICAL TRIAL NUMBER: Clinical Trials.gov #NCT02686762. LAY SUMMARY: Non-alcoholic steatohepatitis (NASH) is characterized by fat accumulation in liver cells, which leads to inflammation and fibrosis. Emricasan was previously shown to inhibit some of the liver enzymes which lead to liver inflammation and fibrosis. In this study, emricasan did not improve liver inflammation or fibrosis in patients with NASH and pre-existing liver fibrosis.

Human keratinocytes express functional CD14 and toll-like receptor 4.

CD14 and the toll-like receptor 4 have been known to play an important role in lipopolysaccharide-induced cellular responses in bacterial infections. Although CD14 and toll-like receptor 4 expression has been demonstrated in a number of myeloid cells, much less is known about the expression and function of these lipopolysaccharide receptors on nonleukocytes. In this study, we demonstrate that human keratinocytes are capable of expressing functional CD14 and toll-like receptor 4. Keratinocytes were found to constitutively express CD14 and toll-like receptor 4 mRNA that was augmented by exposure to lipopolysaccharide. Cell surface expression of keratinocyte CD14 and toll-like receptor 4 was detected by flow cytometry. Lipopolysaccharide binding to keratinocyte CD14 and toll-like receptor 4 resulted in a rapid intracellular Ca2+ response, nuclear factor-kappaB nuclear translocation, and the secretion of proinflammatory cytokines and chemokines. These results have important implications for our understanding of cutaneous innate immunity to bacterial infections of the skin.