1. Are (exogenous) interferons really necessary? Peter Ferenci Medical University of Vienna

2. Treatment of chronic non-A,non-B hepatitis with recombinant human alpha interferon. A preliminary report JH Hoofnagle, KD Mullen, DB Jones, V Rustgi, A Di Bisceglie, M Peters, JG Waggoner, Y Park, and EA Jones Volume 315:1575-1578 December 18, 1986 December 18, 1986 Effect of interferon on experimental vaccinia and herpes-simplex virus infections in rabbits' eyes. CANTELL K, TOMMILA V. Lancet. 1960 Sep 24;2(7152):682-4

3. Role of interferon-alfa in treatment of hepatitis?  Mode of action immune-modulatory (dose dependent!) antiviral antiproliferative  IFN-sensitivity IL28B Nullresponse….

4. 100% 0% 1st dose 14–28 Days HCV RNA Maintenance phase Detection limit Time Course of Virological Response to IFN Therapy in Patients With CHC Inhibition of viral replication Immune system elimination of infected cells ? Induction phase Ferenci P 1999

5. NK cells and response to IFN therapy in patients with CHC Ahlenstiehl et al, Gastroenterology 2011

6. HCV Life Cycle and DAA Targets Adapted from Manns MP, et al. Nat Rev Drug Discov. 2007;6:991-1000. Receptor binding and endocytosis Fusion and uncoating Transport and release (+) RNA Translation and polyprotein processing RNA replication Virion assembly Membranous web ER lumen LD ER lumen LD NS3/4 protease inhibitors NS5B polymerase inhibitors Nucleoside/nucleotide Nonnucleoside *Role in HCV life cycle not well defined NS5A* inhibitors

7. INFORM-1 study: proof of concept study, combination of a PI (danoprevir, DNV) with the polymerase inhibitor mericitabine (MCB) 48w1d4d7d14d 500 mg BID MCB 100 mg TID DNV B n=8/2 1000 mg BID MCB 200 mg TID DNV D n=8/4 TF (non-null) 1000 mg BID MCB 600 mg BID DNV E n=8/2 TF (null) 1000 mg BID MCB 900 mg BID DNV F n=8/2 Naive 1000 mg BID MCB 900 mg BID DNV G n=8/2 Naive P/R (Peg-IFN + RBV) 100 mg TID DNV 500 mg BID MCB 100 mg TID DNV A n=8/0 Active/placebo 500 mg BID MCB 200 mg TID DNV 1000 mg BID MCB 100 mg TID DNV C n=16/2 TF = IFN-treatment failuresGane EJ et al. Lancet 2010

8. Median Log 10 HCV RNA Change from Baseline (IU/mL) Days –6 –5 –4 –3 –2 –1 0 1 02468101214 MCB (mg BID) / DNV (mg) Placebo 500 BID / 100 TID 1000 BID / 100 TID 500 BID / 200 TID 1000 BID / 200 TID 1000 BID / 600 BID (pEVR) 1000 BID / 900 BID (TF - Null) 1000 BID / 900 BID (Naive) Gane EJ et al. Lancet 2010 Median change from baseline by treatment group Cohorts B–G

9. Naive and Null Responders with a BID Oral Regimen of RG7128 and RG7227 Median Log 10 HCV RNA (IU/mL) 1 2 3 4 5 6 7 Days 135791113 Limit of Detection TF - Nulls Naives RG7128 1000 mg BID + RG7227 900 mg BID Gane et al, Lancet 2010 0 10 20 30 40 50 60 70 80 90 100 <LLOQ<LLOD 50 25 88 Nulls Naives Nulls Naives 63

10. GS-9256 + Tegobuvir Alone, With RBV, or With PegIFN/RBV in GT1 Tx-Naive Patients –Phase II study of tegobuvir (GS-9190), an NS5B nonnucleoside polymerase inhibitor, and GS-9256, an NS3 protease inhibitor as part of HCV therapy Zeuzem S, et al. AASLD 2010. Abstract LB-1. GS-9256 75 mg BID + Tegobuvir 40 mg BID (n = 16) † Wk 48 Wk 4 GS-9256 75 mg BID + Tegobuvir 40 mg BID + RBV* † (n = 15) PR* (n = 16) PR* (n = 15) GS-9256 75 mg BID + Tegobuvir 40 mg BID + PR* (n = 15) PR* (n = 15) Part A Part B (nonrandomized) Treatment-naive patients with GT1 HCV *PegIFN alfa-2a 180 µg/wk; weight-based RBV 1000-1200 mg/day. † PegIFN/RBV started early if virologic breakthrough.

11. GS-9256 + Tegobuvir Alone, With RBV, or With PegIFN/RBV: Virologic Response Zeuzem S, et al. AASLD 2010. Abstract LB-1. HCV RNA ResponseGS-9256 + Tegobuvir (n = 15) GS-9256 + Tegobuvir + RBV (n = 13) GS-9256 + Tegobuvir + PegIFN/RBV (n = 14) Median maximal change from baseline, log 10 IU/mL -4.1-5.1-5.7 Achieved nadir ≤ 25 IU/mL, % 1362100 Day 14 HCV RNA ≤ 25 IU/mL, % 74671 Day 28 HCV RNA ≤ 25 IU/mL (RVR), % 738100 Tegubovir requires both pegIFN and RBV program terminated due to safety issues

12. ZENITH: telaprevir (PI) + VX-222 (NNI) ± Peg-IFN/RBV in treatment-naive G1 patients *Based on a 10 day healthy volunteer DDI study; when combined with telaprevir, VX-222 doses of 100 mg and 400 mg provide VX-222 plasma exposures equivalent to 250 mg and 750 mg bid. Nelson D, et al. AASLD 2011. Abstract LB-14. Week012 Telaprevir 1125 mg bid VX-222 100 mg bid* Telaprevir 1125 mg bid VX-222 100 mg bid* RBV Peg-IFN alfa-2a Telaprevir 1125 mg bid VX-222 400 mg bid* Telaprevir 1125 mg bid VX-222 400 mg bid* RBV Peg-IFN alfa-2a D N=30 RBV Peg-IFN alfa-2a RVR2-guided Week 36 A N=18 B N=29 C N=29 DDI = drug-drug interaction; NNI = non-nucleoside inhibitor; Peg-IFN = peginterferon alfa; PI = protease inhibitor; RBV = ribavirin

13. ZENITH: telaprevir (PI) + VX-222 (NNI) ± Peg-IFN/RBV in treatment-naive G1 patients *Based on a 10 day healthy volunteer DDI study; when combined with telaprevir, VX-222 doses of 100 mg and 400 mg provide VX-222 plasma exposures equivalent to 250 mg and 750 mg bid. Nelson D, et al. AASLD 2011. Abstract LB-14. DUAL regimens terminated Week012 Telaprevir 1125 mg bid VX-222 100 mg bid* Telaprevir 1125 mg bid VX-222 100 mg bid* RBV Peg-IFN alfa-2a Telaprevir 1125 mg bid VX-222 400 mg bid* Telaprevir 1125 mg bid VX-222 400 mg bid* RBV Peg-IFN alfa-2a D N=30 RBV Peg-IFN alfa-2a RVR2-guided Week 36 A N=18 B N=29 C N=29

14. Telaprevir 1125 mg bid VX-222 400 mg bid* RBV E/F (E G1b N=23; F G1a N=23) Enrolment complete ZENITH: telaprevir (PI) + VX-222 (NNI) ± Peg-IFN/RBV in treatment-naive G1 patients *Based on a 10 day healthy volunteer DDI study; when combined with telaprevir, VX-222 doses of 100 mg and 400 mg provide VX-222 plasma exposures equivalent to 250 mg and 750 mg bid. Nelson D, et al. AASLD 2011. Abstract LB-14. DUAL regimens terminated Week012 Telaprevir 1125 mg bid VX-222 100 mg bid* Telaprevir 1125 mg bid VX-222 100 mg bid* RBV Peg-IFN alfa-2a Telaprevir 1125 mg bid VX-222 400 mg bid* Telaprevir 1125 mg bid VX-222 400 mg bid* RBV Peg-IFN alfa-2a D N=30 RBV Peg-IFN alfa-2a RVR2-guided Week 36 A N=18 B N=29 C N=29

15. ZENITH: telaprevir + VX-222 ± Peg-IFN/RBV SVR12 data SVR12, % 24 29 27 30 9 11 14 15 13 –No patient in either QUAD arm experienced viral breakthrough. However, 2 patients relapsed in Arm C (7%) and 2 patients (including 1 patient who received only 1 week of treatment) in Arm D (7%) Nelson D, et al. AASLD 2011. Abstract LB-14.

16. MATTERHORN: study design weeks F/U Quad: MCB 1000mg + DNVr 100/100mg + P/R F/U Cohort B: Null Responders A2 A3 IFN free: MCB 1000mg + DNVr 100/100mg + R A1 Triple: DNVr 100/100mg + P/R IFN free: MCB 1000mg + DNVr 100/100mg + R Quad: MCB 1000mg + DNVr 100/100mg + P/R B1 B2 F/U Cohort A: Partial Responders Phase 2, randomized within cohort, open-label, parallel study of 2 cohorts N= 420 (70 pts/arm) Quad: MCB 1000mg + DNVr 100/100mg + P/R F/U B3 48241272 P/R Stratification by: »IL28B (CC, CT, TT) »G1a/1b

17. MATTERHORN: study design weeks F/U Quad: MCB 1000mg + DNVr 100/100mg + P/R F/U Cohort B: Null Responders A2 A3 IFN free: MCB 1000mg + DNVr 100/100mg + R A1 Triple: DNVr 100/100mg + P/R IFN free: MCB 1000mg + DNVr 100/100mg + R Quad: MCB 1000mg + DNVr 100/100mg + P/R B1 B2 F/U Cohort A: Partial Responders Phase 2, randomized within cohort, open-label, parallel study of 2 cohorts N= 420 (70 pts/arm) Quad: MCB 1000mg + DNVr 100/100mg + P/R F/U B3 48241272 P/R Stratification by: »IL28B (CC, CT, TT) »G1a/1b GT1a

18. Zeuzem S, et al. AASLD 2011. Abstract LB-15 Phase 2b SOUND-C2: BI201335 (PI) + BI207127 (NNI) ± RBV in treatment naive G1 patients –Randomization stratified by HCV subtype (G1a vs G1b) and IL28B genotype (rs12979860 CC vs non-CC) –52% of patients were male, 98% White, 38% G1a, 85% had baseline HCV RNA ≥800,000 IU/mL, 10% had compensated cirrhosis, and 25% had IL28B genotype CC Randomization Naive, CHC, G1 N=362 Weeks1640028 BI207127 600 mg tid BI201335 120 mg qd RBV BI207127 600 mg tid BI201335 120 mg qd RBV Follow-up BI207127 600 mg tid BI201335 120 mg qd Follow-up BI207127 600 mg bid BI201335 120 mg qd RBV Follow-up BI207127 600 mg tid BI201335 120 mg qd RBV Follow-up

19. SOUND-C2: preliminary SVR in treatment Arm A (16 week treatment duration, BI201335 + BI207127 + RBV in treatment naive G1 patients) (n=81) Proportion of patients (%) Zeuzem S, et al. AASLD 2011. Abstract LB-15

20. BMS-790052 + BMS-650032 Alone or With PegIFN/RBV in GT1 Null Responders Lok A, et al. NEJM 2012. Prior null responders with GT1 HCV (N = 21) BMS-790052 60 mg QD + BMS-650032 600 mg BID (n = 11) Wk 72 Wk 24 Follow-up BMS-790052 60 mg QD + BMS-650032 600 mg BID + PR* (n = 10)  Open-label, randomized, placebo-controlled phase IIa trial  BMS-790052: NS5A polymerase inhibitor Follow-up *PegIFN alfa-2a 180 µg/wk; weight-based RBV 1000-1200 mg/day.

21. HCV RNA Levels in Groups A and B. Lok AS et al. N Engl J Med 2012;366:216-224

23. BMS-790052/BMS-650032 in Japanese G1b null responders: virological response –1 subject discontinued at Week 2; HCV RNA was undetectable after 24 weeks’ follow-up –No apparent association between detection of baseline RAVs and virological outcome LLOQ = lower limit of quantification (15 IU/mL); RAV = resistance-associated variants Patients (%) RVRcEVREOTRSVR12SVR24 Chayama K, et al. Hepatology 2011; DOI:10.1002/hep.24724.

24. PSI-7977 ELECTRON: PSI-7977 + RBV study design for treatment-naive G2/3 –Treatment-naive, non-cirrhotic, age ≥18 years –HCV RNA >50,000 IU/mL –Allowed concurrent methadone use –Stratified by HCV genotype and IL28B genotype –Randomized 1:1:1:1 into IFN sparing or IFN-free Weeks PSI-7977 + RBV PSI-7977 + RBV + Peg-IFN PSI-7977 + RBV + Peg-IFN PSI-7977 + RBV 128424 SVR12 N=10 Gane EJ, et al. AASLD 2011. Abstract 34

25. PSI-7977 ELECTRON: IFN-free PSI-7977 + RBV achieves 100% SVR12 Gane EJ, et al. AASLD 2011. Abstract 34 PSI-7977 RBV 12 weeks PEG PSI-7977 RBV 8 weeks PEG PSI-7977 RBV 4 weeks PEG PSI-7977 RBV NO PEG Time, week N%<LODN N N 29/11827/8888/9898/1080 411/1110010/101009/910010/10100 811/1110010/101009/910010/10100 12 11/11 100 10/10 100 9/9 10010/10100

26. 26 NS5A NS5B NS2 NS3 NS4B CYCLOPHILIN A IS ESSENTIAL FOR HCV REPLICATION AND IS INHIBITED BY ALISPORIVIR Gallay PA. Clin Liver Dis 2009;13:403–417 ALISPORIVIR Inhibition of replication Replication of new viral RNA NS5A NS5B NS2 NS3 NS4B CypA CypA

27. Phase 2b VITAL-1: alisporivir IFN-free therapy in G2/3 treatment-naive patients Pawlotsky JM, et al. AASLD 2011. Abstract LB-11 Viral response defined by HCV RNA < 25 IU/mL; sc = subcutaneous injection Randomization Screening ALV1000 ALV600R ALV800R ALV-P PR Loading 1 week RVRHCVEVREOTRSVR12SVR24RNA BL14122436486 Week ALV 600 mg bid + RBV 400 mg bid ALV 600 mg bid + RBV 400 mg bid ALV 600 mg bid + Peg-IFN sc weekly RBV 400 mg bid + Peg-IFN 180 mg sc weekly ALV 1000 mg qd ALV 600 mg qd + RBV 400 mg bid ALV 800 mg qd + RBV 400 mg bid ALV 600 mg qd + Peg-IFN 180 mg sc weekly ≥25 IU/mL ALV 600 mg qd+ RBV 400 mg bid + Peg-IFN sc weekly ALV 600 mg qd+ RBV 400 mg bid + Peg-IFN sc weekly ALV 600 mg qd+ RBV 400 mg bid + Peg-IFN sc weekly ALV 600 mg qd+ RBV 400 mg bid + Peg-IFN sc weekly

28. Phase 2b VITAL-1: ALV IFN-free treatment maintains HCV RNA negative response to week 12 Pawlotsky JM, et al. AASLD 2011. Abstract LB-11 Viral response by <LOQ; Analysis for patients who had Week 12 HCV RNA assessment RCR patients On IFN-free treatment IFN-free week 12 results: ALV1000 26%; ALV800R 37%; ALV600R 41% Non-RCR patients with Add-on IFN from week 6 Add-on IFN to non-RVR patients shows rapid response Week Proportion of patients (%) 024681012 20 40 60 80 100 0 ALV 1000 mg (n=55) ALV 600 mg + RBV (n=49) ALV 800 mg + RBV (n=51) ALV 1000 mg (n=22) ALV 600 mg + RBV (n=30) ALV 800 mg + RBV (n=37) Week Proportion of patients (%) 024681012 20 40 60 80 100 0 98% 100% 92%

29. Summary IFN-free therapy –All combinations in early development –SVR close to 100% in G1b –SVR 100% Genotype 2/3 patients –RBV required –Shortening of treatment –role of IL28B Polymorphisms?

30. –If no new safety signals are detected IFN-free therapy of hepatitis C may became reality in 2015 Outlook IFN-free therapy

31. –If no new safety signals are detected IFN-free therapy of hepatitis C may became reality in 2015 Outlook IFN-free therapy and we have reached the “holy grail” of hepatology

33. NK cells in HCV infection and response to IFN therapy in patients with CHC

34. NK cells and response to IFN therapy in patients with CHC Ahlenstiehl et al, Gastroenterology 2011

35. cellular response to HCV infection HCV virus activated kinase IRF-3 IRF-7 IFN production IFN receptor IFN responding genes antiviral proteins