Supplementary Appendix

Transcription

1 Supplementary Appendix This appendix has been provided by the authors to give readers additional information about their work. Supplement to: Jacobson IM, Gordon SC, Kowdley KV, et al. Sofosbuvir for hepatitis C genotype 2 or 3 in patients without treatment options. N Engl J Med 213;368: DOI: 1.156/NEJMoa

2 SUPPLEMENTAL INFORMATION POSITRON PRINCIPAL INVESTIGATORS 4 FUSION PRINCIPAL INVESTIGATORS... 4 SUPPLEMENTARY METHODS Study Design Eligibility Criteria for POSITRON Eligibility Criteria for FUSION Definition of Virologic Failure for Both Studies Statistical Methods POSITRON FUSION Multivariate Analysis SUPPLEMENTARY EFFICACY Study Disposition Figure S1. Patient Disposition in POSITRON Figure S2. Patient Disposition in FUSION Table S1. Reasons for Screen Failure in POSITRON (n=13 of 41 screened) 19 Table S2. Reasons for Screen Failure in FUSION (n=75 of 277 screened) 21 Interferon Classifications Figure S3. Reasons for Interferon Ineligibility in POSITRON Figure S4. Reasons for Interferon Intolerance in POSITRON Analysis of Factors Associated With SVR12 in POSITRON Table S3. SVR12 Rates by Patient Subgroup in POSITRON Table S4. SVR12 in Patients With GT 2 and 3 Infection Receiving SOF+RBV for 12 Weeks by Presence or Absence of Cirrhosis in POSITRON 28 Table S5. Univariate Analysis of Factors Associated With SVR12 in Positron. 29 Table S6. Multivariate Logistic Regression Identifying Factors Associated With SVR12 in POSITRON... 3 Analysis of Factors Associated With SVR12 in FUSION Table S7. SVR Rates by Patient Subgroup in FUSION Table S8. SVR12 in Patients Receiving SOF+RBV for 12 or 16 Weeks by GT 2 or 3 Infection and Presence or Absence of Cirrhosis in FUSION

3 SUPPLEMENTAL INFORMATION (CONTINUED) Table S9. Univariate Analysis of Factors Associated With SVR12 in Patients Receiving 12 Weeks of SOF+RBV in FUSION Table S1. Multivariate Logistic Regression Identifying Factors Associated With SVR12 in Patients Receiving 12 Weeks of SOF+RBV in FUSION.. 36 Table S11. Univariate Analysis of Factors Associated With SVR12 in Patients Receiving 16 Weeks of SOF+RBV in FUSION Table S12. Multivariate Logistic Regression Identifying Factors Associated With SVR12 in Patients Receiving 16 Weeks of SOF+RBV in FUSION.. 38 Resistance in POSITRON and FUSION.. 39 SUPPLEMENTARY SAFETY Table S13. Adverse Events Leading to Discontinuation From Both Study Drugs in POSITRON Table S14. Adverse Events Leading to Discontinuation From Both Study Drugs in FUSION... 4 Table S15. All Treatment-Emergent Adverse Events in POSITRON Table S16. All Treatment-Emergent Adverse Events in FUSION Figure S5. Treatment-Emergent Adverse Events by System-Organ Class in POSITRON Figure S6. Treatment-Emergent Adverse Events by System-Organ Class in FUSION. 55 Table S17. Treatment-Emergent Serious Adverse Events in POSITRON 56 Table S18. Treatment-Emergent Serious Adverse Events in FUSION. 58 Table S19. Adverse Events by Cirrhosis Status in POSITRON 59 Table S2. Adverse Events by Cirrhosis Status in FUSION 6 Figure S7. Hematology Values During Treatment in POSITRON Figure S8. Hematology Values During Treatment in FUSION Table S21. Hematology Abnormalities in POSITRON Table S22. Hematology Abnormalities in FUSION... 7 Figure S9. Treatment-Emergent Hematologic Abnormalities by Grade in POSITRON Figure S1. Treatment-Emergent Hematologic Abnormalities by Grade in FUSION 71 3

4 POSITRON PRINCIPAL INVESTIGATORS Australia: Jacob George, Barbara Leggett, Stephen Pianko, Alexander Thompson Canada: Magdy Elkashab, Alnoor Ramji, Mark Swain, Bernard Willems, Eric Yoshida New Zealand: Edward Gane, Catherine Stedman United States: Nezam Afdhal, Avanish Aggarwal, Leslie Bank, Kimberly Beavers, Michael Bennett, Raymond Chung, Mitchell Davis, Richard Elion, Kyle Etzkorn, Gregory Everson, Bradley Freilich, Michael Galambos, Stuart Gordon, Tarek Hassanein, Robert Herring, Jr, Federico Hinestrosa, Ira Jacobson, Kris Kowdley, Marcelo Kugelmas, Jay Lalezari, Eric Lawitz, Claudia Martorell, Anthony Mills, Giuseppe Morelli, Ronald Nahass, Anders Nyberg, Ponni Perumalswami, Gary Poleynard, K. Rajender Reddy, Maribel Rodriguez-Torres, Peter Ruane, Vinod Rustgi, Michael Ryan, Michael Saag, Eugene Schiff, Thomas Sepe, Aasim Sheikh, Mitchell Shiffman, Coleman Smith, Mark Sulkowski, David Wyles, Ziad Younes, Zobair Younossi FUSION PRINCIPAL INVESTIGATORS Canada: Brian Conway, Curtis Cooper, Magdy Elkashab, Saya Feinman, Jordan Feld, Kelly Kaita, Mang Ma, Alnoor Ramji, Stephen Shafran, Mark Swain, Bernard Willems, Eric Yoshida New Zealand: Edward Gane, Catherine Stedman United States: Nezam Afdhal, Avanish Aggarwal, M. Tarek Al-Assi, Leslie Bank, Kimberly L Beavers, Michael Bennett, Christopher Christensen, Israel Crespo, Mitchell Davis, Kyle Etzkorn, Gregory Everson, Bradley Freilich, Michael Galambos, Stuart Gordon, Tarek Hassanein, Robert Herring, Jr, Federico Hinestrosa, Kris Kowdley, Marcelo Kugelmas, Jay Lalezari, Eric Lawitz, Anthony Martinez, Claudia Martorell, Giuseppe Morelli, Ronald Nahass, Anders Nyberg, Keyur Patel, Ponni Perumalswami, Gary Poleynard, K. Rajender Reddy, Maribel Rodriguez-Torres, Peter Ruane, Vinod Rustgi, Michael Ryan, Eugene Schiff, Thomas Sepe, Aasim Sheikh, Mitchell Shiffman, Coleman Smith, Mark Sulkowski, William Towner, Ziad Younes, Zobair Younossi 4

5 SUPPLEMENTARY METHODS STUDY DESIGN Eligibility Criteria for POSITRON Inclusion Criteria Patients were to meet all of the following inclusion criteria to be eligible for participation in this study: 1. Willing and able to provide written informed consent 2. Male or female, age 18 years 3. Confirmation of chronic hepatitis C virus (HCV) infection documented by either: a) A positive anti-hcv antibody test or positive HCV RNA, or positive HCV genotyping test 6 months prior to the Baseline/Day 1 visit; or b) A liver biopsy performed prior to the Baseline/Day 1 visit with evidence of chronic HCV infection. 4. Cirrhosis determination a) Cirrhosis was defined as any 1 of the following: Liver biopsy showing cirrhosis Fibroscan (in countries where locally approved) showing cirrhosis or results >12.5 kpa A FibroTest score >.75 and an aspartate aminotransferase (AST):platelet ratio index (APRI) >2 during Screening b) Absence of cirrhosis was defined as any 1 of the following: Liver biopsy within 2 years of Screening showing absence of cirrhosis Fibroscan (in countries where locally approved) with a result 12.5 kpa within 6 months of Baseline/Day 1 A FibroTest score.48 and APRI 1 during Screening In the absence of a definitive diagnosis of presence or absence of cirrhosis by the above criteria, a liver biopsy was required. 5. Infection with HCV genotype 2 or 3 as determined at Screening 6. HCV RNA 1 4 IU/mL at Screening 7. Patient were to meet 1 of the following classifications: 5

6 a) Interferon (IFN) unwilling: patient had to have medical records documenting his/her decision declining treatment with an IFN-based regimen 3 months prior to signing the Informed Consent b) IFN ineligible: patient was deemed ineligible by the investigator for treatment with IFN due to 1 of the following comorbidities, which are deemed at risk for worsening with IFN treatment: Autoimmune disorders including but not limited to: dermatomyositis, immune (idiopathic) thrombocytopenic purpura, inflammatory bowel disease, interstitial lung disease, interstitial nephritis, polymyositis, psoriasis, rheumatoid arthritis, sarcoidosis, and systemic lupus erythematosus Significant psychiatric disease necessitating hospitalization or period of disability, or history of psychosis, schizophrenia, bipolar disorder, moderate depression, schizoaffective disorder, suicidal ideation, or suicide attempt Seizure disorder Poorly controlled thyroid dysfunction; hypothyroidism (thyroid-stimulating hormone 2 x the upper limit of normal [ULN] and 1 x ULN) or hyperthyroidism (thyroid-stimulating hormone < the lower limit of normal and >.1 μiu/ml) Retinal disease Poorly controlled diabetes (hemoglobin [Hb]-A1c >6.1% and 1%) Other relative IFN contraindications, including age, which are not specifically listed above, but may have been approved after discussion with the Gilead Medical Monitor c) IFN intolerant: patient completed 12 weeks of treatment (ending 3 months prior to Screening) with IFN and discontinued treatment due to development or significant worsening of 1 of the following conditions: Significant local or systemic adverse reaction to IFN (eg, hypersensitivity and injection-site reactions) Psychiatric disease necessitating hospitalization or period of disability, or psychosis, schizophrenia, bipolar disorder, depression, schizoaffective disorder, suicidal ideation, or suicide attempt Significant cognitive impairment 6

7 Neuropathy Disabling flu-like symptoms (eg, arthralgias, fatigue, pyrexia, and myalgia) Gastrointestinal toxicity with nausea, vomiting, or diarrhea Thrombocytopenia (platelets <25,/μL) Neutropenia (absolute neutrophil count <5/μL) Development of colitis, nonalcoholic pancreatitis, or ophthalmologic disorders Autoimmune disorder including but not limited to: myositis, hepatitis, inflammatory bowel disease, interstitial lung disease, interstitial nephritis, immune (idiopathic) thrombocytopenic purpura, psoriasis, rheumatoid arthritis, sarcoidosis, systemic lupus erythematosus, thrombotic thrombocytopenic purpura, and thyroiditis Adverse event related to IFN that was not listed following consultation with the Gilead Medical Monitor 8. Body mass index 18 kg/m 2 9. Screening electrocardiogram without clinically significant abnormalities 1. Patients had to have the following laboratory parameters at Screening: a) Alanine aminotransferase 1 x ULN b) AST 1 x ULN c) Hb 12 g/dl for male and 11 g/dl for female patients d) Albumin 3 g/dl e) Direct bilirubin 1.5 x ULN f) HbA1c 1% g) Creatinine clearance 6 ml/min, as calculated by the Cockcroft-Gault equation h) International Normalized Ratio (INR) 1.5 x ULN unless the patient had known hemophilia or was stable on an anticoagulant regimen affecting INR 11. Patient had not been treated with any investigational drug or device within 3 days of the Screening visit 12. A female patient was eligible to enter the study if it was confirmed that she was: a) Not pregnant or nursing; 7

8 b) Of nonchildbearing potential (ie, women who had a hysterectomy, both ovaries removed, or medically documented ovarian failure, or were postmenopausal women aged >5 years with cessation [for 12 months] of previously occurring menses); and c) Of childbearing potential (ie, women who had not had a hysterectomy, both ovaries removed, and no medically documented ovarian failure). Women aged 5 years with amenorrhea were considered to be of childbearing potential. These women had to have a negative serum pregnancy test at Screening and a negative urine pregnancy test on the Baseline/Day 1 visit prior to randomization, and agree to 1 of the following from 3 weeks prior to Baseline/Day 1 until 6 months after the last dose of ribavirin (RBV): Complete abstinence from intercourse Consistent and correct use of 1 of the following highly effective methods of birth control, in addition to a male partner who correctly used a condom, from the date of screening until 6 months after the last dose of RBV: Implants of levonorgestrel Injectable progesterone Any intrauterine device with a documented failure rate <1%/year Oral contraceptives (either combined or progesterone only) Vaginal ring plus spermicidal agent Transdermal contraceptive patch Tubal sterilization Vasectomy in male partner 13. All male patients had to agree to consistently and correctly use a condom while their female partner agreed to use 1 of the highly effective methods of birth control listed above from the date of screening until 7 months after their last dose of RBV. 14. Male patients had to agree to refrain from sperm donation for 7 months after the last dose of RBV. 15. Patients had to be of generally good health as determined by the Investigator. 16. Patients had to be able to comply with the dosing instructions for study drug administration and to complete the study schedule of assessments. 17. Liver imaging within 6 months of Baseline/Day 1 was required in cirrhotic patients only to exclude hepatocellular carcinoma. 8

9 Exclusion Criteria Patients who met any of the following exclusion criteria were not to be enrolled in this study: 1. Prior exposure to a direct-acting antiviral targeting the HCV NS5B polymerase 2. Pregnant or nursing female, or male with pregnant female partner 3. Chronic liver disease of a non-hcv etiology (eg, hemochromatosis, Wilson s disease, α1- antitrypsin deficiency, and cholangitis) 4. Infection with hepatitis B virus or HIV 5. Contraindications to RBV therapy 6. History of malignancy diagnosed or treated within 5 years (recent localized treatment of squamous or noninvasive basal cell skin cancers was permitted; cervical carcinoma in situ was allowed if appropriately treated prior to Screening). Patients under evaluation for malignancy were not eligible. 7. History of clinically significant hemoglobinopathy (eg, sickle cell disease and thalassemia) 8. Chronic use of systemically administered immunosuppressive agents (eg, prednisone equivalent >1 mg/day) 9. Clinically relevant drug or alcohol abuse within 12 months of Screening. A positive drug screen excluded patients unless it could be explained by a prescribed medication; the diagnosis and prescription had to be approved by the Investigator. 1. History of solid organ transplantation 11. Current or prior history of clinical hepatic decompensation (eg, ascites, jaundice, encephalopathy, or variceal hemorrhage) 12. History of clinically significant illness or any other major medical disorder that could interfere with patient treatment, assessment, or compliance with the protocol 13. History of a primary gastrointestinal disorder (or postoperative condition) that could interfere with the absorption of the study drug 14. History of significant pulmonary or cardiac disease, or porphyria 15. Excessive alcohol ingestion, defined as >3 glasses/day (1 glass is equivalent to beer 284 ml, wine 125 ml, or distilled spirits 25 ml) for females and >4 glasses/day for males 16. History of difficulty with blood collection and/or poor venous access for the purposes of phlebotomy 17. Donation or loss of >4 ml blood within 2 months prior to Day 1 9

10 18. Use of any prohibited concomitant medications within 28 days of the Baseline/Day 1 visit 19. Known hypersensitivity to RBV, the study investigational medicinal product, the metabolites, or formulation excipients Eligibility Criteria for FUSION Inclusion Criteria Patients were to meet all of the following inclusion criteria to be eligible for participation in this study; 1. Willing and able to provide written informed consent 2. Male or female aged 18 years 3. Confirmation of chronic HCV infection documented by either: c) A positive anti-hcv antibody test, positive HCV RNA, or positive HCV genotyping test 6 months prior to the Baseline/Day 1 visit; or d) A liver biopsy performed prior to the Baseline/Day 1 visit with evidence of chronic HCV infection. 4. Cirrhosis determination a) Cirrhosis was defined as any 1 of the following: Liver biopsy showing cirrhosis Fibroscan (in countries where locally approved) showing cirrhosis or results >12.5 kpa A FibroTest score >.75 and an APRI >2 performed during Screening b) Absence of cirrhosis was defined as any 1 of the following: Liver biopsy within 2 years of Screening showing absence of cirrhosis Fibroscan (in countries where locally approved) with a result 12.5 kpa within 6 months of Baseline/Day 1 A FibroTest score.48 and APRI 1 performed during Screening In the absence of a definitive diagnosis of presence or absence of cirrhosis by the above criteria, a liver biopsy was required. Liver biopsy results superseded the results obtained by Fibroscan or FibroTest. 5. Infection with HCV genotype 2 or 3 as determined at Screening 6. HCV RNA 1 4 IU/mL at Screening 1

11 7. Prior treatment failure with IFN for 12 weeks with or without RBV. Permissible IFNs included IFN α-2a (Roferon-A ), peginterferon α-2a (Pegasys ), IFN α-2b (Intron A ), peginterferon α-2b (PegIntron ), and IFN alfacon-1 (Infergen ). 8. The patient s medical records had to include sufficient detail of prior treatment with IFN to allow for categorization of prior response as either: a) Nonresponse: patient did not achieve undetectable HCV-RNA levels on treatment; or b) Relapse/breakthrough: patient achieved undetectable HCV-RNA levels during treatment or within 4 weeks after treatment. 9. Body mass index 18 kg/m 2 1. Screening electrocardiogram without clinically significant abnormalities 11. Patients had to have the following laboratory parameters at screening: a) Alanine aminotransferase 1 x ULN b) AST 1 x ULN c) Hb 12 g/dl for male and 11 g/dl for female patients d) INR 1.5 x ULN unless the patient had known hemophilia or was stable on an anticoagulant regimen affecting INR e) Platelets 5,/ L f) Albumin 3 g/dl g) Direct bilirubin 1.5 x ULN h) HbA1c 1% i) Creatinine clearance 6 ml/min, as calculated by the Cockcroft-Gault equation 12. Patient had not been treated with any investigational drug or device within 3 days of Screening 13. A female patient was eligible to enter the study if it was confirmed that she was: e) Not pregnant or nursing; f) Of nonchildbearing potential (ie, women who had a hysterectomy, both ovaries removed, or medically documented ovarian failure, or were postmenopausal women aged >5 years with cessation [for 12 months] of previously occurring menses); and g) Of childbearing potential (ie, women who had not had a hysterectomy, both ovaries removed, or medically documented ovarian failure). Women aged 5 years with 11

12 amenorrhea were considered to be of childbearing potential. These women had to have a negative serum pregnancy test at Screening and a negative urine pregnancy test on the Baseline/Day 1 visit prior to randomization, and agree to 1 of the following from 3 weeks prior to Baseline/Day 1 until 6 months after the last dose of RBV: Complete abstinence from intercourse Consistent and correct use of 1 of the following methods of birth control, in addition to a male partner who correctly used a condom, from the date of Screening until 6 months after the last dose of RBV: Implants of levonorgestrel Injectable progesterone Any intrauterine device with a documented failure rate <1%/year Oral contraceptives (either combined or progesterone only) Female barrier method: cervical cap or diaphragm with spermicidal agent Contraceptive vaginal ring Transdermal contraceptive patch Tubal sterilization Vasectomy in male partner 14. All male patients had to agree to consistently and correctly use a condom while their female partner agreed to use 1 of the methods of birth control listed above from the date of Screening until 7 months after their last dose of RBV. 15. Male patients had to agree to refrain from sperm donation for 7 months after the last dose of RBV. 16. Patients had to be of generally good health as determined by the Investigator. 17. Patients had to be able to comply with the dosing instructions for study drug administration and to complete the study schedule of assessments. 18. Liver imaging within 6 months of Baseline/Day 1 was required in cirrhotic patients only to exclude hepatocellular carcinoma. Exclusion Criteria Patients who met any of the following exclusion criteria were not to be enrolled in this study. 1. Prior exposure to a direct-acting antiviral targeting the HCV NS5B polymerase 12

13 2. Pregnant or nursing female, or male with pregnant female partner 3. Chronic liver disease of a non-hcv etiology (eg, hemochromatosis, Wilson s disease, α1 antitrypsin deficiency, and cholangitis) 4. Infection with hepatitis B virus or HIV 5. Contraindication to RBV therapy 6. History of malignancy diagnosed or treated within 5 years (recent localized treatment of squamous or noninvasive basal cell skin cancers was permitted; cervical carcinoma in situ was allowed if appropriately treated prior to Screening). Patients under evaluation for malignancy were not eligible. 7. History of clinically significant hemoglobinopathy (eg, sickle cell disease and thalassemia) 8. Chronic use of systemically administered immunosuppressive agents (eg, prednisone equivalent >1 mg/day) 9. Clinically relevant drug or alcohol abuse within 12 months of Screening. A positive drug screen excluded patients unless it could be explained by a prescribed medication; the diagnosis and prescription had to be approved by the Investigator. 1. History of solid organ transplantation 11. Current or prior history of clinical hepatic decompensation (eg, ascites, jaundice, encephalopathy, and variceal hemorrhage) 12. History of clinically significant illness or any other major medical disorder that could interfere with patient treatment, assessment, or compliance with the protocol 13. History of a gastrointestinal disorder (or postoperative condition) that could interfere with the absorption of the study drug 14. History of significant pulmonary or cardiac disease, or porphyria 15. Excessive alcohol ingestion, defined as >3 glasses/day (1 glass is equivalent to beer 284 ml, wine 125 ml, or distilled spirits 25 ml) for females and >4 glasses/day for males 16. History of difficulty with blood collection and/or poor venous access for the purposes of phlebotomy 17. Donation or loss of >4 ml of blood within 2 months prior to Baseline/Day Use of any prohibited concomitant medications within 28 days of the Baseline/Day 1 visit 19. Known hypersensitivity to RBV, the study investigational medicinal product, the metabolites, or formulation excipients 13

14 DEFINITION OF VIROLOGIC FAILURE FOR BOTH STUDIES Virologic failure is defined as confirmed HCV RNA LLOQ after 2 consecutive HCV RNA <LLOQ, confirmed >1 log 1 increase in HCV RNA from on-treatment nadir, HCV RNA LLOQ through 8 weeks of treatment, or HCV RNA LLOQ during the post-treatment period having achieved HCV RNA <LLOQ at end of treatment, confirmed with 2 consecutive values or last available post-treatment measurement. 14

15 STATISTICAL METHODS POSITRON In POSITRON, the primary efficacy endpoint was the superiority of SOF + RBV over placebo compared using a Cochran-Mantel-Haenszel test stratified by the presence or absence of cirrhosis using the efficacy analysis set. The P value associated with the test of superiority was calculated and superiority was demonstrated if the 2-sided Cochran-Mantel-Haenszel test P value was less than the.5 significance level. A sample size of 18 patients in the active arm and 6 in the placebo arm would be sufficient to detect a 4% difference in sustained virologic response (SVR) between the 2 arms (using the 2-sided continuity-corrected chi-square test; α=.5) with 99% power. Multivariate logistic-regression analyses involving the treatment regimen and prespecified baseline characteristics and demographics were performed to evaluate SVR. A stepwise procedure was used to identify independent predictors of SVR. FUSION In FUSION, the primary efficacy endpoint was SVR at 12 weeks (SVR12) after treatment in all randomized and treated patients. A sample size of 1 patients in each group would provide >97% power to detect 2% improvement in SVR12 rate from a historic control rate of 25% using 2-sided exact 1-sample binomial test at a.25 significance level. Gilead had originally calculated a historic control SVR12 rate of 18.5% for the population enrolled in FUSION. The assumptions for this calculation were: 1. The FUSION study population would comprise 76.4% with prior relapse/breakthrough and 23.6% with prior nonresponse. 2. Approximately 5% of the FUSION population could be classified as IFN intolerant/ineligible/unwilling, and this proportion would have an effective SVR rate of 5% as there are no treatment options for this population. 3. The remaining 5% of the FUSION population would have a response rate similar to that reported in the EPIC study for patients with genotype 2/3 HCV previously treated with pegylated IFN and RBV: SVR rates of 57% and 36% in patients with a prior relapse and nonresponse, respectively. (Poynard T, Colombo M, Bruix J, et al. Peginterferon alfa-2b and 15

16 ribavirin: effective in patients with hepatitis C who failed interferon alfa/ribavirin therapy. Gastroenterology 29;136: ) 4. A 1% discount in efficacy due to an expected improved safety profile and shorter duration of treatment (48 vs 12 or 16 weeks) Historic control SVR12 = (.764 x (.5 x 57% +.5 x 5%)) + (.236 x (.5 x 36% +.5 x 5%)) 1 = (.764 x (31%)) + (.236 x (2.5%)) 1 = (23.7% + 4.8%) 1 = 18.5% The US Food and Drug Administration agreed that the calculation of historical SVR data as a reference was complicated in this population and recommended a simplified statistical approach using a rate of 25%. The sample size would also provide 82% power to detect a difference of 2% in SVR12 rates (5% vs 7%) between the 12- and 16-week treatment groups. The secondary analysis of comparing the SVR rates in the 12- and 16-week treatment arms was performed using a Cochran-Mantel-Haenszel test stratified by the randomization stratification factors. Multivariate logistic-regression analyses involving treatment regimens and prespecified baseline characteristics and demographics were performed to evaluate SVR. A stepwise procedure was used to identify independent predictors of SVR. Multivariate Analysis Multivariate logistic-regression (prespecified exploratory) analyses were performed for patients who took SOF and RBV to study which variables were associated with higher SVR rates. A stepwise procedure was used to identify independent predictors of SVR (with P=.1 as the threshold level for variables to be entered into and P=.5 for those to be retained in the final model). All baseline clinical/demographic factors delineated in the univariate logistic regression model in Tables S5, S9, and S11 were candidate variables for inclusion in the multivariate model using the stepwise procedure described above. 16

17 SUPPLEMENTARY EFFICACY STUDY DISPOSITION Figure S1. Patient Disposition in POSITRON 41 patients were screened 28 underwent randomization 29 were assigned to SOF + RBV 27 received assigned treatment 2 were not treated 71 were assigned to placebo 71 received assigned treatment 6 discontinued treatment 4 due to AEs 2 were lost to follow-up 3 discontinued treatment 3 due to AEs 21 completed assigned treatment 68 completed assigned treatment 24 returned for post-treatment Wk 4 visit SVR4 in 172/27 (83%) 71 returned for post-treatment Wk 4 visit SVR4 in /71 1 death 171 returned for post-treatment Wk 12 visit SVR12 in 161/27 (78%) SOF+RBV Placebo Total Patients screened, n 41 Screen failure patients who were not randomized, n 13 Patients randomized, n Patients randomized but never treated, n 2 2 Patients in safety analysis set Patients in full analysis set Study treatment status, n (%) Completed study treatment 21 (97) 68 (96) 269 (97) Discontinued study treatment 6 (3) 3 (4) 7 (3) Reason for premature discontinuation of treatment, n (%) AE 4 (2) 3 (4) 7 (3) Lost to follow-up 2 (1) 2 (1) AE, adverse event; RBV, ribavirin; SOF, sofosbuvir; SVR4, sustained virologic response at Week 4; SVR12, SVR at Week

18 Figure S2. Patient Disposition in FUSION 277 patients were screened 22 underwent randomization 13 were assigned to SOF + RBV 12 wk 13 received assigned treatment 99 were assigned to SOF+RBV 16 wk 98 received assigned treatment 1 was not treated 1 discontinued treatment 1 due to AEs 12 completed assigned treatment 98 completed assigned treatment 99 returned for post-treatment Wk 4 visit SVR4 in 56/1 (56%) 95 returned for post-treatment Wk 4 visit SVR4 in 73/95 (77%) 54 returned for post-treatment Wk 12 visit SVR12 in 5/1 (5%) 73 returned for post-treatment Wk 12 visit SVR12 = 69/95 (73%) SOF+RBV 12 Weeks SOF+RBV 16 Weeks Total Patients screened, n 277 Screen failure patients who were not randomized, n 75 Patients randomized, n Patients randomized but never treated, n 1 1 Patients in safety analysis set, n Patients in full analysis set, n Study treatment status, n Completed study treatment Discontinued study treatment 1 (1) 1 (1) Reason for premature discontinuation of treatment, n AE 1 (1) 1 (1) Lost to follow-up 2 (2) 2 AE, adverse event; RBV, ribavirin; SOF, sofosbuvir; SVR4, sustained virologic response at Week 4; SVR12, SVR at Week 12 18

19 Table S1. Reasons for Screen Failure in POSITRON (n=13 of 41 screened) Screen failure patients who did not meet criteria Inclusion criteria 23 Laboratory parameters at screening: ALT 1 x ULN, AST 1 x ULN, Hgb 12 g/dl for M and 11 g/dl for F, albumin = 3 g/dl, direct bili 1.5 x ULN, HbA1c 1%, CLcr 6 ml/min 22 Infection with HCV genotype 2 or 3 13 Cirrhosis determination a) Cirrhosis is defined as any one of the following: Liver biopsy showing cirrhosis Fibroscan (in countries where locally approved) showing cirrhosis or results >12.5 kpa A FibroTest score of >.75 AND an AST:platelet ratio index (APRI) of >2 performed during screening b) Absence of cirrhosis is defined as any one of the following: Liver biopsy within 2 years of Screening showing absence of cirrhosis Fibroscan (in countries where locally approved) with a result of 12.5 kpa within 6 months of Baseline/Day 1 A FibroTest score of.48 AND APRI of 1 performed during Screening In absence of a definitive diagnosis of presence or absence of cirrhosis by above criteria, liver biopsy is required 7 HCV RNA 1 4 IU/mL at screening 5 Patients meets one of the following classifications: a) IFN unwilling b) IFN ineligible c) IFN intolerant 4 Patient must be able to comply with the dosing instructions for study drug administration and able to complete the study schedule of assessments 2 Patient must be of generally good health as determined by the investigator 2 Liver imaging within 6 months of Baseline/Day 1 is required in cirrhotic patients only, to exclude hepatocellular carcinoma (HCC) 1 Willing and able to provide written informed consent 1 Female patient confirmed she is: not pregnant or nursing, of non-childbearing potential, or of childbearing potential with negative pregnancy test and agrees 19

20 to abstinence or birth control Exclusion criteria 8 Clinically-relevant drug or alcohol abuse within 12 months of screening 2 Infection with hepatitis B virus (HBV) or human immunodeficiency virus (HIV) 1 Pregnant or nursing female or male with pregnant female partner 1 Chronic liver disease of a non-hcv etiology 1 Current or prior history of clinical hepatic decompensation 1 History of a primary gastrointestinal disorder (or post-operative condition) that could interfere with the absorption of the study drug 1 Excessive alcohol ingestion, defined as >3 glasses/day (1 glass is equivalent to: beer [284 ml], wine [125 ml], or distilled spirits [25 ml]) for females and >4 glasses/day for males) 1 Use of any prohibited concomitant medications within 2 weeks of the Baseline/Day 1 visit Screen failure patients who did meet criteria Reason for exclusion 25 Study enrollment closed 8 Other 6 Withdrew consent 3 Investigator s discretion 2 Outside of visit window 1 Lost to follow-up 2

21 Table S2. Reasons for Screen Failure in FUSION (n=75 of 277 screened) Screen failure patients who did not meet criteria Inclusion criteria 2 Subjects must have the following laboratory parameters at screening: a) ALT 1 the upper limit of normal (ULN) b) AST 1 ULN c) Hemoglobin 12 g/dl for male, 11 g/dl for female subjects d) INR 1.5 x ULN unless subject has known hemophilia or is stable on an anticoagulant regimen affecting INR e) Platelets 5, /μl f) Albumin 3 g/dl g) Direct bilirubin 1.5 ULN h) HbA1c 1% i) Creatinine clearance (CLcr) 6 ml/min, as calculated by the Cockcroft-Gault equation 13 The subject s medical records must include sufficient detail of prior treatment with IFN to allow for categorization of prior response as either: Non-Response: Subject did not achieve undetectable HCV RNA levels on treatment Relapse/Breakthrough: Subject achieved undetectable HCV RNA during treatment or within 4 weeks after treatment 6 HCV RNA 1 4 IU/mL at Screening 5 Cirrhosis determination: a) Cirrhosis is defined as any one of the following: Liver biopsy showing cirrhosis Fibroscan (in countries where locally approved) showing cirrhosis or results >12.5 kpa A FibroTest score of >.75 AND an AST:platelet ratio index (APRI) of >2 performed during screening b) Absence of cirrhosis is defined as any one of the following: Liver biopsy within 2 years of Screening showing absence of cirrhosis Fibroscan (in countries where locally approved) with a result of 12.5 kpa within 6 months of Baseline/Day 1 A FibroTest score of.48 AND APRI of 1 performed during Screening In absence of a definitive diagnosis of presence or absence of cirrhosis by above criteria, liver biopsy is required Liver biopsy results supersede the results obtained by Fibroscan or FibroTest 21

22 5 Infection with HCV genotype 2 or 3 as determined at Screening 3 Confirmation of chronic HCV infection documented by either: a) a positive anti-hcv antibody test or positive HCV RNA or positive HCV genotyping test at least 6 months prior to the Baseline/Day 1 visit, or b) a liver biopsy performed prior to Baseline/Day 1 visit with evidence of chronic HCV 3 Prior treatment failure with 12 weeks IFN either with or without RBV. Permissible IFNs include interferon alfa-2a (Roferon-A ), peginterferon alfa-2a (Pegasys ), interferon alfa-2b (Intron A ), peginterferon alfa-2b (PegIntron ) and interferon alfacon-1 (Infergen ) 2 Liver imaging within 6 months of Baseline/Day 1 is required in cirrhotic patients only to exclude hepatocellular carcinoma (HCC) 1 Willing and able to provide written informed consent 1 Body mass index (BMI) 18 kg/m 2 1 Screening ECG without clinically significant abnormalities Exclusion criteria 6 Clinically-relevant drug or alcohol abuse within 12 months of screening. A positive drug screen will exclude subjects unless it can be explained by a prescribed medication; the diagnosis and prescription must be approved by the investigator 4 Use of any prohibited concomitant medications within 28 days of Baseline/Day 1 visit 3 History of malignancy diagnosed or treated within 5 years (recent localized treatment of squamous or non-invasive basal cell skin cancers is permitted; cervical carcinoma in situ is allowed if appropriately treated prior to screen); subjects under evaluation for malignancy are not eligible 3 Current or prior history of clinical hepatic decompensation (e.g., ascites, jaundice, encephalopathy or variceal hemorrhage) 1 Prior exposure to a direct-acting antiviral targeting the HCV NS5B polymerase 1 History of significant pulmonary disease, significant cardiac disease or porphyria 1 Excessive alcohol ingestion, defined as >3 glasses/day (1 glass is equivalent to: beer [284 ml], wine [125 ml], or distilled spirits [25 ml]) for females and >4 glasses/day for males) Screen failure patients who did meet criteria Reason 3 Subject withdrew consent 2 Study enrollment closed 1 Other 22

23 INTERFERON CLASSIFICATIONS Figure S3. Reasons for Interferon Ineligibility in POSITRON Reason, n (%) SOF+RBV Placebo Total Autoimmune disorder 16 (18.2) 7 (21.2) 23 (19.) Poorly controlled diabetes 5 (5.7) 1 (3.) 6 (5.) Retinal disease 4 (4.5) 2 (6.1) 6 (5.) Seizure disorder 4 (4.5) 4 (3.3) Significant psychiatric disease 5 (56.8) 19 (57.6) 69 (57.) Thyroid dysfunction 1 (1.1) 1 (.8) Other (as approved by Medical Monitor) 8 (9.1) 4 (12.1) 12 (9.9) Cardiac issues 1 (3.) 1 (.8) Chronic pain syndrome 1 (3.) 1 (.8) Interferon could retrigger drug addiction 1 (1.1) 1 (.8) Intracranial aneurysm increased risk for seizure 1 (3.) 1 (.8) Migraines 1 (1.1) 1 (.8) Neuropathy 1 (1.1) 1 (.8) Peripheral neuropathy interferon intolerable 1 (1.1) 1 (.8) Patient had vision in only 1 eye and Investigator did not want to risk retinal disease, a side effect of interferon 1 (1.1) 1 (.8) Systemic reaction during previous treatment 1 (1.1) 1 (.8) Thrombocytopenia 2 (2.3) 1 (3.) 3 (2.5) RBV, ribavirin; SOF, sofosbuvir. 23

24 Figure S4. Reasons for Interferon Intolerance in POSITRON Reason, n (%) SOF+RBV Placebo Total Adverse event related to interferon (as approved by Medical Monitor) 1 (5.9) 1 (4.) Development of colitis, nonalcoholic pancreatitis 1 (5.9) 1 (4.) Disabling flu-like symptoms 6 (35.3) 2 (25.) 8 (32.) Gastrointestinal toxicity 1 (5.9) 1 (4.) Neuropathy 1 (12.5) 1 (4.) Neutropenia 1 (12.5) 1 (4.) Psychiatric disease 3 (17.6) 2 (25.) 5 (2.) Significant local or systemic adverse reaction 3 (17.6) 3 (12.) Thrombocytopenia 2 (11.8) 2 (25.) 4 (16.) RBV, ribavirin; SOF, sofosbuvir. 24

25 ANALYSIS OF FACTORS ASSOCIATED WITH SVR12 IN POSITRON Table S3. SVR12 Rates by Patient Subgroup in POSITRON Subgroup SOF+RBV (n=27) Placebo (n=71) SOF+RBV vs Placebo Prop Diff () Overall 161/27 (77.8%) / % (71.%, 83.6%) Age at baseline <5 yr 53/72 (73.6%) 61.9%, 83.3% /2.%, 16.8% 73.6% (55.9%, 83.3%) 5 yr 18/135 (8.%) 72.3%, 86.4% /51.%, 7.% 8.% (72.1%, 86.4%) Sex Male 85/117 (72.6%) 63.6%, 8.5% /34.%, 1.3% 72.6% (62.2%, 8.5%) Female 76/9 (84.4%) 75.3%, 91.2% /37.%, 9.5% 84.4% (74.6%, 91.2%) Race Black 95%CI 8/9 (88.9%) 51.8%, 99.7% /4.%, 6.2% 88.9% (28.7%, 99.7%) Nonblack 153/198 (77.3%) 7.8%, 82.9% /67.%, 5.4% 77.3% (7.7%, 83.%) Ethnicity Hispanic/Latino 14/19 (73.7%) 48.8%, 9.9% /11.%, 28.5% 73.7% (38.9%, 9.9%) Non-Hispanic/-Latino 147/188 (78.2%) 71.6%, 83.9% /6.%, 6.% 78.2% (71.4%, 83.9%) 25

26 Table S3. SVR12 Rates by Patient Subgroup in POSITRON (Continued) Subgroup SOF+RBV (n=27) Placebo (n=71) SOF+RBV vs Placebo Prop Diff () Cirrhosis No 142/176 (8.7%) 74.1%, 86.2% /58.%, 6.2% 8.7% (73.9%, 86.2%) Yes 19/31 (61.3%) 42.2%, 78.2% /13.%, 24.7% 61.3% (31.6%, 78.2%) HCV GT GT 2 11/19 (92.7%) 86.%, 96.8% /34.%, 1.3% 92.7% (83.5%, 96.8%) GT 3 6/98 (61.2%) 5.8%, 7.9% /37.%, 9.5% 61.2% (5.4%, 71.%) Baseline HCV RNA <6 log 1 IU/mL 51/67 (76.1%) 64.1%, 85.7% /17.%, 19.5% 76.1% (56.2%, 85.8%) 6 log 1 IU/mL 11/14 (78.6%) 7.8%, 85.1% /54.%, 6.6% 78.6% (7.7%, 85.1%) Baseline BMI <3 kg/m 2 13/136 (75.7%) 67.6%, 82.7% /49.%, 7.3% 75.7% (67.4%, 82.7%) 3 kg/m 2 58/71 (81.7%) 7.7%, 89.9% /22.%, 15.4% 81.7% (65.1%, 89.9%) Region US 13/168 (77.4%) 7.3%, 83.5% /6.%, 6.% 77.4% (7.2%, 83.5%) Non-US 31/39 (79.5%) 63.5%, 9.7% /11.%, 28.5% 79.5% (48.2%, 9.9%) 26

27 Table S3. SVR12 Rates by Patient Subgroup in POSITRON (Continued) Subgroup SOF+RBV (n=27) Placebo (n=71) SOF+RBV vs Placebo Prop Diff () Baseline ALT category 1.5 x ULN 71/9 (78.9%) 69.%, 86.8% /29.%, 11.9% 78.9% (67.1%, 87.3%) >1.5 x ULN 9/117 (76.9%) 68.2%, 84.2% /42.%, 8.4% 76.9% (67.8%, 84.3%) IL28B CC 74/97 (76.3%) 66.6%, 84.3% /29.%, 11.9% 76.3% (63.9%, 84.7%) Non-CC 87/11 (79.1%) 7.3%, 86.3% /42.%, 8.4% 79.1% (69.9%, 86.3%) Duration on prior HCV treatment No 14/17 (82.4%) 75.8%, 87.8% /56.%, 6.4% 82.4% (75.5%, 87.8%) 12 wk 15/21 (71.4%) 47.8%, 88.7% /8.%, 36.9% 71.4% (24.5%, 88.7%) >12 wk 6/16 (37.5%) 15.2%, 64.6% /7.%, 41.% 37.5% (-5.4%, 64.6%) IFN classification Ineligible 69/88 (78.4%) 68.4%, 86.5% /33.%, 1.6% 78.4% (67.3%, 86.7%) Intolerant 13/17 (76.5%) 5.1%, 93.2% /8.%, 36.9% 76.5% (34.9%, 93.2%) Unwilling 79/12 (77.5%) 68.1%, 85.1% /3.%, 11.6% 77.5% (65.3, 85.3%) ALT, alanine aminotransferase; BMI, body mass index; CI, confidence interval; HCV, hepatitis C virus; IFN, interferon; IL, interleukin; Prop Diff, proportional difference; RBV, ribavirin; SOF, sofosbuvir; SVR12, sustained virologic response at Week 12; ULN, upper limit of normal. 27

28 Table S4. SVR12 in Patients With GT 2 and 3 Infection Receiving SOF+RBV for 12 Weeks by Presence or Absence of Cirrhosis in POSITRON GT 2 (n=19) GT 3 (n=98) SVR12 11/19 (93%) 6/98 (61%) Cirrhosis 16/17 (94%) 3/14 (21%) No cirrhosis 85/92 (92%) 57/84 (68%) GT, genotype; RBV, ribavirin; SOF, sofosbuvir; SVR12, sustained virologic response at Week

29 Table S5. Univariate Analysis of Factors Associated With SVR12 in POSITRON Variable Odds Ratio 95% Confidence Limit 2-Sided P Value Age group: < vs 5 yr.697 (.356, 1.366).29 Sex: female vs male 2.44 (1.15, 4.116).45 Race: black vs nonblack (.287, ).43 Ethnicity: Hispanic/Latino vs non-hispanic/-latino.781 (.266, 2.295).65 Cirrhosis: no vs yes (1.169, 5.952).19 Baseline HCV RNA < vs 6 log 1 IU/mL.869 (.435, 1.736).69 < vs 8, IU/mL (.596, 2.718).53 IL28B: CC vs non-cc.851 (.441, 1.639).63 HCV GT: 2 vs (3.498, ) <.1 Baseline BMI: < vs 3 kg/m 2.7 (.341, 1.434).33 Baseline ALT vs >1.5 x ULN (.577, 2.178).74 Adherence to both drugs: < vs 8%.946 (.356, 2.513).91 Region: Non-US vs US (.481, 2.669).78 Baseline GGT as continuous variable 1. (.995, 1.5).96 Interferon class Interferon ineligible vs unwilling 1.57 (.531, 2.14).87 Interferon intolerant vs unwilling.946 (.281, 3.183).93 Duration on prior HCV treatment: 12 weeks vs no.536 (.192, 1.494).23 >12 weeks vs no.129 (.43,.381) <.1 *Patient 7332 had overdose (OD) of ribavirin (RBV) 16 mg at baseline due to misunderstanding. ALT, alanine aminotransferase; BMI, body mass index; GGT, γ-glutamyl transpeptidase; GT, genotype; HCV, hepatitis C virus; SVR12, sustained virologic response at Week 12; ULN, upper limit of normal. 29

30 Table S6. Multivariate Logistic Regression Identifying Factors Associated With SVR12 in POSITRON Variable Odds Ratio 95% Confidence Limit 2-Sided P Value Sex: female vs male (1.198, 5.94).163 HCV GT: 2 vs (3.616, 2.732) <.1 Duration on prior HCV treatment: 12 weeks vs no.567 (.179, 1.798).335 >12 weeks vs no.131 (.38,.452).13 GT, genotype; HCV, hepatitis C virus; SVR12, sustained virologic response at Week 12. 3

31 ANALYSIS OF FACTORS ASSOCIATED WITH SVR12 IN FUSION Table S7. SVR Rates by Patient Subgroup in FUSION Subgroup SOF+RBV 12 Wk +Placebo 4 Wk (n=1) SOF+RBV 16 Wk (n=95) SOF+RBV 12 Wk +Placebo 4 Wk vs SOF+RBV 16 Wk Prop Diff () Overall 5/1 (5.%) 69/95 (72.6%) -23.4% (-35.4%, -11.4%) Age at baseline <5 yr 9/21 (42.9%) 16/23 (69.6%) -26.7% (-53.6%, 4.8%) 21.8%, 66.% 47.1%, 86.8% 5 yr 41/79 (51.9%) 53/72 (73.6%) -21.7% (-36.7%, -6.1%) 4.4%, 63.3% 61.9%, 83.3% Sex Male 3/71 (42.3%) 42/64 (65.6%) -23.4% (-39.3%, -6.1%) 3.6%, 54.6% 52.7%, 77.1% Female 2/29 (69.%) 27/31 (87.1%) -18.1% (-39.6%, 3.8%) 49.2%, 84.7% 7.2%, 96.4% Race Black 5/5 (1.%) 1/1 (1.%) % (-56.5%, 97.5%) 95%CI 47.8%, 1.% 2.5%, 1.% Nonblack 45/95 (47.4%) 68/94 (72.3%) -25.% (-38.3%, -1.9%) 37.%, 57.9% 62.2%, 81.1% Ethnicity Hispanic/Latino 4/1 (4.%) 5/8 (62.5%) -22.5% (-65.%, 26.%) 12.2%, 73.8% 24.5%, 91.5% Not Hispanic/Latino 46/9 (51.1%) 63/86 (73.3%) -22.1% (-36.%, -7.6%) 4.3%, 61.8% 62.6%, 82.2% 31

32 Table S7. SVR Rates by Patient Subgroup in FUSION (Continued) Subgroup SOF+RBV 12 Wk +Placebo 4 Wk (n=1) SOF+RBV 16 Wk (n=95) SOF+RBV 12 Wk +Placebo 4 Wk vs SOF+RBV 16 Wk Prop Diff () Cirrhosis No 39/64 (6.9%) 48/63 (76.2%) -15.3% (-31.1%, 1.6%) 47.9%, 72.9% 63.8%, 86.% Yes 11/36 (3.6%) 21/32 (65.6%) -35.1% (-56.%, -8.6%) 16.3%, 48.1% 46.8%, 81.4% HCV GT GT 2 31/36 (86.1%) 3/32 (93.8%) -7.6% (-24.1%, 8.5%) 7.5%, 95.3% 79.2%, 99.2% GT 3 19/64 (29.7%) 39/63 (61.9%) -32.2% (-48.1%, -14.7%) 18.9%, 42.4% 48.8%, 73.9% Baseline HCV RNA <6 log 1 IU/mL 13/26 (5.%) 18/29 (62.1%) -12.1% (-37.6%, 15.1%) 29.9%, 7.1% 42.3%, 79.3% 6 log 1 IU/mL 37/74 (5.%) 51/66 (77.3%) -27.3% (-42.3%, -11.%) 38.1%, 61.9% 65.3%, 86.7% Baseline BMI <3 kg/m 2 39/71 (54.9%) 43/61 (7.5%) -15.6% (-31.7%, 1.2%) 42.7%, 66.8% 57.4%, 81.5% 3 kg/m 2 11/29 (37.9%) 26/34 (76.5%) -38.5% (-59.8%, -12.1%) 2.7%, 57.7% 58.8%, 89.3% Region US 38/71 (53.5%) 56/73 (76.7%) -23.2% (-38.3%, -6.4%) 41.3%, 65.5% 65.4%, 85.8% Non-US 12/29 (41.4%) 13/22 (59.1%) -17.7% (-44.2%, 11.%) 23.5%, 61.1% 36.4%, 79.3% 32

33 Table S7. SVR Rates by Patient Subgroup in FUSION (Continued) Subgroup SOF+RBV 12 Wk +Placebo 4 Wk (n=1) SOF+RBV 16 Wk (n=95) SOF+RBV 12 Wk +Placebo 4 Wk vs SOF+RBV 16 Wk Prop Diff () Baseline ALT category 1.5 x ULN 26/4 (65.%) 32/41 (78.%) -13.% (-33.2%, 7.%) 48.3%, 79.4% 62.4%, 89.4% >1.5 x ULN 24/6 (4.%) 37/54 (68.5%) -28.5% (-45.6%, -9.7%) 27.6%, 53.5% 54.4%, 8.5% IL28B CC 15/3 (5.%) 19/27 (7.4%) -2.4% (-45.3%, 5.6%) 31.3%, 68.7% 49.8%, 86.2% Non-CC 35/7 (5.%) 5/68 (73.5%) -23.5% (-39.%, -6.4%) 37.8%, 62.2% 61.4%, 83.5% Response to prior HCV treatment Nonresponse 11/25 (44.%) 16/25 (64.%) -2.% (-46.6%, 8.9%) 24.4%, 65.1% 42.5%, 82.% Relapse/breakthrough 39/75 (52.%) 53/7 (75.7%) -23.7% (-38.8%, -7.8%) 4.2%, 63.7% 64.%, 85.2% ALT, alanine aminotransferase; BMI, body mass index; CI, confidence interval; HCV, hepatitis C virus; IL, interleukin; Prop Diff, proportional difference; RBV, ribavirin; SOF, sofosbuvir; SVR12, sustained virologic response at Week 12; ULN, upper limit of normal. 33

34 Table S8. SVR12 in Patients Receiving SOF+RBV for 12 or 16 Weeks by GT 2 or 3 Infection and Presence or Absence of Cirrhosis in FUSION Subgroup Genotype 2 SOF+RBV 12 Wk +Placebo 4 Wk (n=1) SOF+RBV 16 Wk (n=95) SOF+RBV 12 Wk +Placebo 4 Wk vs SOF+RBV 16 Wk Prop Diff () No cirrhosis 25/26 (96.2%) 23/23 (1%) -3.8% (-2.2%, 11.3%) 8.4%, 99.9% 85.2%, 1% Cirrhosis 6/1 (6.%) 7/9 (77.8%) -17.8% (-58.%, 26.8%) 26.2%, 87.8% 4.%, 97.2% Genotype 3 No cirrhosis 14/38 (36.8%) 25/4 (62.5%) -25.7% (-46.5%, -2.9%) 21.8%, 54.% 45.8%, 77.3% Cirrhosis 5/26 (19.2%) 14/23 (6.9%) -41.6% (-65.%, -11.8%) 6.6%, 39.4% 38.5%, 8.3% CI, confidence interval; GT, genotype; Prop Diff, proportional difference 34

35 Table S9. Univariate Analysis of Factors Associated With SVR12 in Patients Receiving 12 Weeks of SOF+RBV in FUSION Variable Odds Ratio 95% Confidence Limit 2-Sided P Value Age group: < vs 5 yr.695 (.263, 1.834).46 Sex: female vs male 3.36 (1.214, 7.594).18 Race: black vs nonblack Not est Not est Not est Ethnicity: Hispanic/Latino vs non-hispanic/-latino.638 (.168, 2.413).51 Cirrhosis: no vs yes (1.487, 8.454).4 Baseline HCV RNA < vs 6 log 1 IU/mL 1. (.49, 2.444) 1. < vs 8, IU/mL.893 (.352, 2.269).81 IL28B: CC vs non-cc 1. (.425, 2.352) 1. HCV GT: 2 vs (4.956, 43.58) <.1 Baseline BMI: < vs 3 kg/m (.824, 4.827).13 Baseline ALT: vs >1.5 x ULN (1.215, 6.388).16 Adherence to both drugs: < vs 8%.638 (.168, 2.413).51 Response to prior HCV treatment: nonresponse vs relapse/breakthrough.725 (.292, 1.83).49 Region: Non-US vs US.613 (.256, 1.469).27 Baseline GGT as continuous variable.992 (.985,.998).7 Baseline weight-based RBV dose (1.5, 1.69).18 ALT, alanine aminotransferase; BMI, body mass index; est, estimated; GGT, γ-glutamyl transpeptidase; GT, genotype; HCV, hepatitis C virus; RBV, ribavirin; SOF, sofosbuvir; SVR12, sustained virologic response at Week 12; ULN, upper limit of normal. 35

36 Table S1. Multivariate Logistic Regression Identifying Factors Associated With SVR12 in Patients Receiving 12 Weeks of SOF+RBV in FUSION Variable Odds Ratio 95% Confidence Limit 2-Sided P Value HCV GT: 2 vs (6.144, ) <.1 Baseline weight-based RBV dose (1.89, 1.983).119 Cirrhosis: no vs yes (1.19, 9.537).463 GT, genotype; HCV, hepatitis C virus; RBV, ribavirin; SOF, sofosbuvir; SVR12, sustained virologic response at Week

37 Table S11. Univariate Analysis of Factors Associated With SVR12 in Patients Receiving 16 Weeks of SOF+RBV in FUSION Variable Odds Ratio 95% Confidence Limit 2-Sided P Value Age group: < vs 5 yr.819 (.292, 2.298).71 Sex: female vs male (1.97, 11.39).34 Race: black vs nonblack Not est Not est Not est Ethnicity: Hispanic/Latino vs non- Hispanic/-Latino.68 (.135, 2.751).52 Cirrhosis: no vs yes (.66, 4.256).28 Baseline HCV RNA < vs 6 log 1 IU/mL.481 (.187, 1.239).13 < vs 8, IU/mL.522 (.187, 1.46).22 IL28B: CC vs non-cc.855 (.319, 2.292).76 HCV GT: 2 vs (2.21, 42.16).4 Baseline BMI: < vs 3 kg/m (.28, 1.929).53 Baseline ALT: vs >1.5 x ULN (.64, 4.166).3 Adherence to both drugs: < vs 8%.621 (.166, 2.327).48 Response to prior HCV treatment: nonresponse vs relapse/breakthrough.57 (.213, 1.523).26 Region: Non-US vs US.438 (.16, 1.22).11 Baseline GGT as continuous variable.999 (.996, 1.3).8 Baseline weight-based RBV dose 1.6 (.796, 1.272).96 ALT, alanine aminotransferase; BMI, body mass index; est, estimated; GGT, γ-glutamyl transpeptidase; GT, genotype; HCV, hepatitis C virus; RBV, ribavirin; SOF, sofosbuvir; SVR12, sustained virologic response at Week 12; ULN, upper limit of normal. 37

38 Table S12. Multivariate Logistic Regression Identifying Factors Associated With SVR12 in Patients Receiving 16 Weeks of SOF+RBV in FUSION Variable Odds Ratio 95% Confidence Limit 2-sided P Value HCV GT: 2 vs (2.251, ).28 Sex: female vs male (1.169, ).271 GT, genotype; HCV, hepatitis C virus; RBV, ribavirin; SOF, sofosbuvir; SVR12, sustained virologic response at Week

39 RESISTANCE IN POSITRON AND FUSION POSITRON Forty-two patients relapsed after stopping treatment. Full-length NS5B was successfully sequenced in 34 patients. In 5 patients, a short fragment covering amino acid residue 282 was generated and deep sequenced (in 4 patients) or population sequenced (in 1 patient). Samples were not available for 2 patients and the assay was not successful for another. No previously identified SOF- or RBV-associated mutations in NS5B were detected in any of these patients. Five other NS5B substitutions were observed in >2 subjects. No reduction in susceptibility to SOF or RBV was observed among patient samples containing substitutions, indicating that NS5B amino acid changes observed at relapse did not reduce the viral sensitivity to SOF or RBV. FUSION Seventy-three patients relapsed after stopping treatment. Full-length NS5B sequence results were successfully obtained from 66 patients by deep sequencing. A short fragment flanking position 282 was obtained by deep sequencing from 5 additional patients and population sequencing from the remaining 2 patients. No SOF associated mutation (S282T) in nonstructural protein 5B (NS5B) was detected by deep sequencing or population sequencing in any patient. Eleven NS5B substitutions were observed in >2 subjects. No reduction in susceptibility to SOF or RBV was observed among patient samples containing substitutions, indicating that NS5B amino acid changes observed at relapse did not reduce the viral sensitivity to SOF or RBV. 39

40 SUPPLEMENTARY SAFETY Table S13. Adverse Events Leading to Discontinuation From Both Study Drugs in POSITRON Adverse Event* SOF+RBV (n=27) Placebo (n=71) Overall 5 (2.4) 3 (4.2) Anemia 1 (.5) Abdominal pain upper 1 (.5) Pancreatitis 1 (1.4) Chest discomfort 1 (.5) Edema peripheral 1 (1.4) Injury 1 (.5) Road traffic accident 1 (.5) ALT increased 1 (1.4) Muscle spasms 1 (.5) Anxiety 1 (.5) Insomnia 1 (.5) Rash 1 (1.4) *No. (%) of patients experiencing any adverse event leading to permanent discontinuation from any of the study drugs by preferred term. ALT, alanine aminotransferase; RBV, ribavirin; SOF, sofosbuvir. Table S14. Adverse Events Leading to Discontinuation From Both Study Drugs in FUSION Adverse Event* SOF+RBV 12 Weeks (n=13) SOF+RBV 16 Weeks (n=98) Overall 1 (1.) Abdominal pain 1 (1.) Pyrexia 1 (1.) *A single patient in the SOF+RBV 12-week arm of FUSION discontinued treatment during the placebo period due to abdominal pain and pyrexia. RBV, ribavirin; SOF, sofosbuvir. 4

41 Table S15. All Treatment-Emergent Adverse Events in POSITRON 41

42 Table S15. All Treatment-Emergent Adverse Events in POSITRON (Continued) 42

43 Table S15. All Treatment-Emergent Adverse Events in POSITRON (Continued) 43

44 Table S15. All Treatment-Emergent Adverse Events in POSITRON (Continued) 44

45 Table S15. All Treatment-Emergent Adverse Events in POSITRON (Continued) 45

46 Table S15. All Treatment-Emergent Adverse Events in POSITRON (Continued) 46

47 Table S15. All Treatment-Emergent Adverse Events in POSITRON (Continued) RBV, ribavirin; SOF, sofosbuvir. 47

48 Table S16. All Treatment-Emergent Adverse Events in FUSION RBV, ribavirin; SOF, sofosbuvir. 48

49 Table S16. All Treatment-Emergent Adverse Events in FUSION (Continued) RBV, ribavirin; SOF, sofosbuvir. 49

50 Table S16. All Treatment-Emergent Adverse Events in FUSION (Continued) RBV, ribavirin; SOF, sofosbuvir. 5

51 Table S16. All Treatment-Emergent Adverse Events in FUSION (Continued) RBV, ribavirin; SOF, sofosbuvir. 51

52 Table S16. All Treatment-Emergent Adverse Events in FUSION (Continued) RBV, ribavirin; SOF, sofosbuvir. 52

53 Table S16. All Treatment-Emergent Adverse Events in FUSION (Continued) RBV, ribavirin; SOF, sofosbuvir. 53

54 Table S16. All Treatment-Emergent Adverse Events in FUSION (Continued) RBV, ribavirin; SOF, sofosbuvir. 54

55 Figure S5. Treatment-Emergent Adverse Events by System-Organ Class in POSITRON Figure S6. Treatment-Emergent Adverse Events by System-Organ Class in FUSION 55