Potent HCV Antiviral Activity by Inhibiting Fatty November 11, Acid Synthase 2012 AASLD George Kemble, PhD CSO
Drug Profile: Rationale & Approach • Unique mechanism of action to enable the following: – Pan genotype antiviral activity – Activity against other classes of drug resistant HCV mutants – Well tolerated – High barrier to resistance • Approach – Identify a cellular protein that is: • required for HCV replication • not critical for day to day function of the host – Develop proprietary compounds that fit with the evolving SOC 2
Fatty Acid Synthase (FASN) Large, homodimer • FASN Multiple enzymatic domains • Acetyl-CoA + Palmitate 7 Malonyl-CoA + ATP, NADPH Other fatty Diglycerides acids & complex & lipids Triglycerides Post- translational modifications (eg NS4b) Adult mice lacking liver FASN are normal Maier, et al. Science, 2002 PDB ID: 2CF2 Chakravarthy, et al, Cell Metabolism, 2005 3
HCV Depends on the FASN Pathway FASN and/or its product interact with HCV at multiple points of the viral replication cycle Viral Entry RNA Replication Virus Assembly and Exit Yang, et al, Hepatol. (2008) Yu, et al, J. Virol (2006) Sakamoto, et al. Nat. Chem Biol (2005) Umehara, et al., Biochem & Biophys Res. Comm (2006) Majeau, et al, J. Biol. Chem (2009) Moradpour et al. Nature Reviews Microbiology (2007) 4
3-V Inhibitors Are Potent & Specific GT1b Replicon Infectious HCV (Gt2a) Inhibitory (50%) Concentration FASN FASN Enzyme GT1b GT2a Enzyme in vitro in cells Replicon* Virus* 50 nM 40 nM 60 nM 41 nM *No toxicity observed at highest concentration tested (10,000 nM) 5
FASN Inhibition Blocks HCV RNA Replication & Protein Expression Inhibition of HCV RNA Replication 100.0 % Luciferase Inhibition 80.0 60.0 40.0 20.0 0.0 48 72 96 3-V FASN Inhibitor Treatment (hrs) NS5a Ab No Drug 6
FASN Inhibition Reduces HCV RNA In Passaged Cell Lines 100 (normalized to GAPHD) % HCV RNA Relative to 75 Untreated Cells 50 No Drug Prot. Inhib 3-V FASN Inhib 25 0 0 5 10 15 20 25 Days Post Treatment 7
Targeted Inhibition of FASN Palmitate add-back demonstrates on-target mechanism HCV Replicon FASN inhibitor HCV RNA replication (Luciferase) + / - Palmitate FASN enzymatic activity (palmitate synthesis) 1.5 synthesis (response) de novo PMT Response de novo palmitate TVB-0002722 3-V inhib. 3-V inhib. 3-V inhib. + 10 µ M palmitate TVB-0002722 + PA 10uM 3-V inhib.+ 10 µ M palmitate 1.0 3-V inhib. + 25 µ M palmitate 3-V inhib. + 25 µ M palmitate TVB-0002722 + PA 25uM 3-V inhib. + 50 µ M palmitate 3-V inhib. + 50 µ M palmitate TVB-0002722 + PA 50uM 0.5 0.0 10 - 5 10 - 4 10 - 3 10 - 2 10 - 1 10 0 10 1 10 2 Concentration, uM Concentration, µ M Concentration, µ M FASN is inhibited HCV RNA repl is restored 8
3-V FASN inhibitors active against a range of HCV variants Median E fg ectiveness Concentration ( µ M) Active across genotypes Gt1a Gt1b Gt2 0.06 0.06 0.10 120 % Activity Compared to WT replicon 90 3-V inhibitor 60 Control Cmpds 30 (DAAs) 0 Active against replicons resistant to other classes of HCV drugs Drug Resistant Mutation in Gt1b Replicon 9
FASN inhibited in rats following oral administration * 150 * % FASN Activity 125 Harvest Liver 100 Analyze 13 C Palmitate 75 12 or 24 hours 50 25 Add 3-V FASN inhibitor 13 C Acetate Oral gavage 0 Tracer (t=0) Veh 30 60 Veh 30 60 (t=10 or 22 hrs) mpk mpk mpk mpk 12 hr 24 hr post dose post dose P<0.05 Mann-Whitney 10
Profile of 3-V’s FASN inhibitors • Attractive compounds with unique mechanism of action – On-target activity confirmed – Potent (EC 50 ’s < 100nM) – Pan genotype antiviral activity – Active against HCV mutants resistant to various classes of DAAs – Well tolerated following multiple day dosing at levels that suppress liver FASN in rats • IND enabling studies underway • Phase 1 and proof of concept in HCV patients in 2013 11
3-V Biosciences, Inc. Contributors Doug Buckley Marc Evanchik Robert McDowell Stefan Moese Yamini Ohol Johan D. Oslob Visit Poster #1876 Merdad Parsey for additional information Amy K. Patick Mohan Sivaraja Sam Tep Satya Yendluri
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