1. Francesco Negro University Hospitals, Geneva, Switzerland Future treatment of HCV with Host Targeting Antivirals

2. Host-Targeting Antivirals (HTA) vs. Direct Acting Antivirals (DAA)  Less or no risk of selecting drug resistance  Pan-genotypic activity  Risk of toxicity due to interference with cellular functions PRO’s CON’s

3. Host factors as target for anti-HCV therapy Compound Host factor targeted HCV life cycle phase targeted Current clinical phase CD81 antibodiesCD81EntryPreclinical ITX 5061 (iTherX)SCARB1Entry1b EzetimibeNPC1L1EntryPreclinical ErlotinibEGF-REntryPreclinical DasatinibEphrin RA2EntryPreclinical Alisporivir (Novartis)CypARNA replication3 (siRNA) PI4KIII-  RNA replicationPreclinical MiravirsenmiR122RNA replication2 StatinsHMGCoARRNA replicationNA (siRNA)DGAT1AssemblyPreclinical Celgosivir  -glucosidase I Assembly/releaseTerminated Adapted from VON HAHN et al, 2011; HERKER et al, 2010; SAINZ et al, 2012 TROTARD et al, 2009; LUPBERGER et al, 2011

4. Alisporivir (DEBIO-025), a cyclophilin inhibitor without immunosuppressive effects DEBIO-025CsA Cyclophilin binding domain Calcineurin binding domain

5. Alisporivir binds to cyclophilin but not to calcineurin NF-ATc P Cyclosporin A- cyclophilin complex binds calcineurin CyP CsA CN NF-ATc P Activation of immune response NF-ATc NF-ATc dephosphorylation is blocked alisporivir Alisporivir-Cyp complex does NOT bind to CN leaving immune response intact CyP CN

6. CYCLOPHILINS ARE CHAPERONES  Cyclophilins have diverse cellular functions  Ubiquitous proteins –Expressed in various tissues (liver, muscle, CNS) –>7 subtypes reported in humans –Detected in cytosol, nucleus, ER, mitochondria (depending on subtype)  Peptidyl prolyl isomerase (PPIase) activity –Catalyzes isomerization of peptidic bonds from trans to cis to facilitate the de novo protein unfolding –HCV exploits the PPIase activity of CypA for its own replication PENG et al, 2005; RYFFEL et al, 1991; COLGAN, et al. 2004

7. Cyclophilin A (CyPA) is the main cyclophilin involved in HCV replication 7 Yang F, et al. J Virol 2008;82:5269–5278; Chatterji U, et al. J Biol Chem 2009;284:16998–17005 Kaul A, et al. PLoS Pathog 2009;5:e1000546

8. Additional effects of cyclophilin inhibition in HCV infection  Restoration of mitochondrial function QUARATO et al, Hepatology 2011  Reduction of autophagy, thus limiting the inhibitory effect of autophagy on innate immune response CARREIRA et al, Autophagy 2010

9. Alisporivir Pan-genotype antiviral activity As a monotherapy or added to SOC, G1-4 High resistance barrier Mutations associated with resistance to Cyp inhibitors can be selected in vitro within NS5A (a substrate of PPIase activity of CypA) but appear very slowly (28 passages, 4-6 months) The D320E (domain III of NS5A) mutation is associated with resistance to alisporivir (cross-resistance to CsA and alisporivir) but is not sufficient to lead to breakthrough in patients Resistance is low-level (<5-fold) and involves reduced binding to CyPA FLISIAK et al, Hepatology 2009; FERNANDEZ et al. Hepatology 2007; GOTTO et al, Cancer Sci 2009 CRABBE et al Expert Opin Investig Drugs 2009; WIEDERMANN et al, Antimicrob Agents Chemother 2010 FLISIAK et al, EASL 2011; CHATTERJI et al, J Hepatol 2010; COLMONT et al, PLoS One 2010

10. Alisporivir monotherapy or in combination with SOC [4 weeks, treatment-naive, HCV genotypes 1 and 4] FLISIAK et al, Hepatology 2009;49:1460–1468

11. Alisporivir monotherapy or in combination with SOC [4 weeks, treatment-naive, HCV genotypes 2 and 3]

12. Dreaming about an IFN-  -free world...

13. Alisporivir-RGT (n=71) Alisporivir + PEG-IFN-  /RBV 24-48 weeks PEG-IFN-  /RBV (n=73) Placebo + PEG-IFN-  /RBV 48 weeks The ESSENTIAL Study (205 Study) Multicenter (EU), 48 weeks, treatment-naive, HCV-1, phase IIb RCT ITT population (n=288) Alisporivir48 (n=72) Alisporivir + PEG-IFN-  /RBV 48 weeks 600 mg BID first week then 600 mg QD RVR non-RVR Alisporivir24 (n=72) Alisporivir + PEG-IFN-  /RBV 24 weeks FU FLISIAK et al, EASL 2011 0247248

14. The ESSENTIAL Study – SVR ITT population (n=288) 39/73 54/72 49/7134/72 FLISIAK et al, EASL 2011 P=0.008

15. The ESSENTIAL Study (205 Study) ITT population (n=288)  Alisporivir + PEG-IFN-  /RBV is superior to PEG-IFN-  /RBV: –RVR was ~3-fold higher in all alisporivir-containing arms –SVR increased from 55% to 76% in the 48-week triple regimen –Improvement of SVR was independent of IL28B genotype –Triple regimen was well tolerated (transient, reversible hyperbilirubinemia in ~1/3 of patients, without cholestasis or hepatotoxicity) FLISIAK et al, EASL 2011

16. Alisporivir disposal and risk of DDIs  DEB025 is mainly metabolised through cytochrome P450 3A4  DEB025 is an inhibitor of P-gp, BSEP, MRP2 (leading to hyperbilirubinemia), NTCP, OATP1B1 and OATP1B3 16

17. Alisporivir – Ongoing phase III program Patients’ populationComparator HCV GT 1 naivePegIFN + RBV HCV GT 1 naïve, African AmericanBOC+PegIFN+RBV

18. miRNA-122 is essential to HCV replication Miravirsen (Santaris) is a small LNA modified phosphorothioate anti-sense oligonucleotide targeting (and blocking) miR-122 JOPLIN et al, Science 2005; JANSSEN et al, AASLD 2011

19. Preclinical and phase 1 data on Miravirsen LANFORD et al, Science 2010; ELMEN et al, Nature 2008  Miravirsen inhibits HCV in vitro (EC 50 0.67  m)  No resistance-conferring mutations in the miR-122 seed regions (conserved among HCV genotypes)  In healthy volunteers, safe and well tolerated, with no dose limiting toxicity

20. Proof-of-concept study of Miravirsen (oligonucleotide targeting miR-122) in treatment-naïve HCV-1 JANSSEN et al, AASLD 2011

21. Mean HCV RNA Log changes during Miravirsen JANSSEN et al, AASLD 2011 No evidence of drug resistance Prolonged dose-dependent antiviral activity well beyond the end of therapy, consistent with 30 day terminal half-life