1. 5/14/2015 1 Interim Results from HCV SPRINT-1 Phase 2 Study of Boceprevir Plus Peginterferon alfa-2b/Ribavirin in Treatment-Naïve Subjects with Genotype-1 CHC T. Poynard, MD

2. 5/14/2015 2 HCV SPRINT-1 Investigators Luis Balart Thomas Boyer Robert Brown William Cassidy Raymond Chung Gary Davis Mitchell Davis Steven Flamm Bradley Freilich Joseph Galati Greg Galler Reem Ghalib Alexandra Gibas Eliot Godofsky Jorge Herrera Ira Jacobson Shobha Joshi John King Paul Kwo Eric Lawitz William Lee James Levin Jonathan McCone Timothy Morgan Frederick Nunes Lisa Marie Nyberg Mary Pat Pauly Craig Peine Gary Poleynard Fred Poordad David Pound Natarajan Ravendhran Lorenzo Rossaro Raymond Rubin Michael Ryan Eugene Schiff Kenneth Sherman Mitchell Shiffman Coleman Smith Robert Strauss Mark Sulkowski John Vierling Ziad Younes Frank Anderson Jenny Heathcote Paul Marotta Stephen Shafran Michael Adler Rafael Barcena Thomas Berg Marc Bourliere Jean-Pierre Bronowicki Giampiero Carosi Antonio Craxi Rafael Esteban-Mur Xavier Forns Christophe Hezode Michael Manns Patrick Marcellin Fredrik Nevens Claus Niederau Thierry Poynard Jurg Reichen Henk Reesink Mario Rizzetto Christian Trepo Stefan Zeuzem USCanada EU

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4. 5/14/2015 4 Aims of the Study  To evaluate the most effective treatment strategy in HCV-1 treatment naïve patients  Duration of therapy  28 weeks vs. 48 weeks  Lead-in strategy with Peginterferon alfa-2b + ribavirin followed by boceprevir 800 mg TID vs. Triple therapy from Day 1  Standard vs low dose ribavirin  800-1400 mg/day vs 400-1000 mg/day  To evaluate the predictability of Week 4 and 12 HCV-RNA undetectability on SVR

5. 5/14/2015 5 Study Design PEG 1.5 µg/kg + REBETOL 800-1400 mg + boceprevir 800 mg TID for 48 weeks PEG 1.5 µg/kg + REBETOL 800-1400 mg + boceprevir 800 mg TID for 28 weeks No Lead-in Dosing Strategy PEG 1.5 µg/kg + REBETOL 400-1000 mg + boceprevir 800 mg TID for 48 weeks Low dose REBETOL Dosing Strategy PEG 1.5 µg/kg + REBETOL 800-1400 mg for 48 weeks Control PEG 1.5 µg/kg + REBETOL 800-1400 mg + boceprevir 800 mg TID for 24 weeks PEG 1.5 µg/kg + REBETOL 800-1400 mg + boceprevir 800 mg TID for 44 weeks PEG-INTRON + REBETOL 800-1400 mg x 4 weeks Lead-in Dosing Strategy Follow-up x 44 weeks Follow-up x 24 weeks Follow-up x 44 weeks

6. 5/14/2015 6 SVR Data Available for Interim Analysis PEG 1.5 µg/kg + REBETOL 800-1400 mg + boceprevir 800 mg TID for 28 weeks No Lead-in Dosing Strategy PEG 1.5 µg/kg + REBETOL 800-1400 mg + boceprevir 800 mg TID for 24 weeks PEG-INTRON + REBETOL 800-1400 mg x 4 weeks Lead-in Dosing Strategy Follow-up x 44 weeks SVR 12

7. 5/14/2015 7 Baseline Characteristics P/R lead-in→ P/R/boceprevir, N=103 ‡ P/R/boceprevir,N=107 P/R Control, N=104 Gender Male (%) 505967 Race Caucasian (%) 838080 Mean age (years) 47.746.448.3 Mean weight (kg) 79.983.483.4 HCV Subtype (%) 1a516351 1b362840 Viral load mean (log 10 IU/mL) 6.56.66.5 HCV-RNA >600,000 IU/mL (%) 879290 Cirrhosis (%) 778 ‡ Boceprevir added to treatment regimen after 4 week lead-in of PEG-IFN α-2b + ribavirin.

8. 5/14/2015 8 HCV-1 Patients with Undetectable HCV-RNA* at Weeks 4 and 12 of Boceprevir Therapy (ITT) * Roche TaqMan 1.0 (LLD 15 IU/mL) ‡ Boceprevir added to treatment regimen after 4 week lead-in of PEG-IFN α-2b + ribavirin. P/R lead-in → P/R/boceprevir, N=103 ‡ P/R/boceprevir, N=107P/R control, N=104

9. 5/14/2015 9 Just Available Data SVR for 28/48 Weeks and Peg/riba Control

10. 5/14/2015 10 Sustained Virologic Response* for 28/48 Weeks and P/R Control *SVR 12 or later timepoint ‡ Boceprevir added to treatment regimen after 4 week lead-in of PEG-IFN α-2b + ribavirin. 28 Wks n=103 48 Wks n=103 28 Wks n=107 28 Wks n=107 48 Wks n=103

11. 5/14/2015 11 Safety for 28 Weeks of Treatment

12. 5/14/2015 12 Treatment Discontinuations x 28 Weeks P/R lead-in→ P/R/boceprevir, N=103 (%) ‡ P/R/boceprevir, N=107 (%) P/R Control, N=104 (%) Total Discontinued 27 (26) 30 (28) 15 (14) Adverse Events 15 (15) 12 (11) 8 (8) Viral Breakthrough 4 (4) 7 (7) 0 Other* 8 (8) 11 (10) 7 (7) * Lost to Follow Up, Subject Did Not Wish to Continue, Non-compliance with Protocol ‡ Boceprevir added to treatment regimen after 4 week lead-in of PEG-IFN α-2b + ribavirin.

13. 5/14/2015 13 Most Common Adverse Events x 28 Weeks (≥15% in any Arm) P/R lead-in→ P/R/boceprevir, N=103 (%) ‡ P/R/boceprevir, N=107 (%) P/R Control, N=104 (%) Fatigue686155 Anemia535534 Nausea413843 Headache404942 Chills302934 Alopecia293426 Insomnia283437 Pyrexia262634 Diarrhea262623 Dysgeusia26219 Irritability232322 Arthralgia211318 Cough211718 Influenza-Like Illness 202223 Neutropenia172312 Pruritis181815 Dizziness161815 Dyspnoea121714 Anxiety91618 Dry skin 81116 ‡ Boceprevir added to treatment regimen after 4 week lead-in of PEG-IFN α-2b + ribavirin.

14. 5/14/2015 14 Skin and Subcutaneous Disorders* x 28 Weeks *Includes rash (all types), eczema, erythema, photosensitivity reaction, dermatitis, skin irritation and skin exfoliation. § Severe Erythema. Patient was in PEG-IFN α-2b + ribavirin lead in; never received boceprevir ‡ Boceprevir added to treatment regimen after 4 week lead-in of PEG-IFN α-2b + ribavirin. P/R lead-in → P/R/boceprevir, N=103 ‡ P/R/boceprevir, N=107P/R control, N=104

15. 5/14/2015 15 Hemoglobin: Worst WHO Grade Category Observed During Treatment x 28 Weeks † P/R lead-in → P/R/boceprevir, N=206 ‡ P/R/boceprevir, N=226P/R control, N=104 † Epoetin-alfa use allowed; 48% in P/R lead-in, 45% in P/R/boceprevir, 25% in P/R control ‡ Boceprevir added to treatment regimen after 4 week lead-in of PEG-IFN α-2b + ribavirin.

16. 5/14/2015 16 Summary of Interim Results  Boceprevir with P/R X 28 and 48 weeks  Greater SVR than P/R alone X 48 weeks in HCV-1 naïve patients. 1-4  Safety  Boceprevir containing regimens appear to be well- tolerated.  Incidence of rash and pruritis comparable to Control.  No boceprevir-defining toxicity responsible for treatment discontinuation. 1 Fried M, et al. N Engl J Med 2002;347:975-82. 2 Manns M, et al. Lancet 2001; 358: 958–65. 3 Sulkowski M, et al. Abstract #LB 2, EASL 2008. 4 Jacobson I, et al. Hepatology 2007;46:982-990.