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Featured researches published by Steven J. Knox.
Lancet Infectious Diseases | 2015
Masashi Mizokami; Osamu Yokosuka; Tetsuo Takehara; Naoya Sakamoto; Masaaki Korenaga; Hitoshi Mochizuki; Kunio Nakane; Hirayuki Enomoto; Fusao Ikeda; Mikio Yanase; Hidenori Toyoda; Takuya Genda; Takeji Umemura; Hiroshi Yatsuhashi; Tatsuya Ide; Nobuo Toda; Kazushige Nirei; Yoshiyuki Ueno; Yoichi Nishigaki; Juan Betular; Bing Gao; Akinobu Ishizaki; Masa Omote; Hongmei Mo; Kim Garrison; Phillip S. Pang; Steven J. Knox; William T. Symonds; John G. McHutchison; Namiki Izumi
BACKGROUND Compared with other countries, patients with chronic hepatitis C infection in Japan tend to be older, have more advanced liver disease, and are more likely to have been previously treated for hepatitis C. We aimed to assess the efficacy and safety of an all-oral, fixed-dose combination of the hepatitis C virus NS5A inhibitor ledipasvir and the NS5B nucleotide polymerase inhibitor sofosbuvir with and without ribavirin for 12 weeks in treatment-naive and previously treated Japanese patients with chronic genotype 1 hepatitis C virus infection. METHODS In this randomised, open-label study, we enrolled patients from 19 clinical Japanese centres. Patients were randomly assigned (1:1) to receive either ledipasvir (90 mg) and sofosbuvir (400 mg) or ledipasvir, sofosbuvir, and ribavirin (dosed according to the Japanese Copegus product label-ie, patients ≤60 kg received 600 mg daily, patients >60 kg to ≤80 kg received 800 mg daily, and patients >80 kg received 1000 mg daily) orally once daily for 12 weeks. After completion or early discontinuation of treatment, patients were followed up off-treatment for 24 weeks. Eligible patients were at least 20 years of age with chronic genotype 1 hepatitis C virus infection with serum hepatitis C virus RNA concentrations of at least 5 log10 IU/mL, creatinine clearance of at least 1·0 mL/s, and a platelet count of at least 50 × 10(9) per L. An interactive web response system was used to manage patient randomisation and treatment assignment. Randomisation was stratified by the presence or absence of cirrhosis for treatment-naive patients and stratified by presence or absence of cirrhosis and by previous treatment category (relapser or breakthrough, non-responder, or interferon-intolerant) for previously treated patients. Within each strata, patients were sequentially assigned to either treatment with ledipasvir-sofosbuvir or ledipasvir-sofosbuvir plus ribavirin in a 1:1 ratio with block size of 4. The primary endpoint was sustained virological response 12 weeks after completion of treatment (SVR12) assessed in all patients who were randomly assigned and received at least one dose of study drug; safety outcomes were assessed in all patients who received at least one dose of study drug. This trial is registered with ClinicalTrials.gov, number NCT01975675. FINDINGS Between Oct 15, 2013 and Dec 13, 2013, 341 patients were randomly assigned to treatment groups and received at least one dose of study treatment. SVR12 was achieved in all 171 (100%) patients (83 of 83 treatment naive and 88 of 88 treatment experienced) receiving ledipasvir-sofosbuvir (95% CI 98-100) and 167 (98%) of 170 patients (80 of 83 treatment naive and 87 of 87 treatment experienced) receiving ledipasvir-sofosbuvir plus ribavirin (95% CI 95-100). Of the 76 patients with baseline NS5A resistant variants, 75 (99%) achieved SVR12. Two (1·2%) of 170 patients in the ledipasvir-sofosbuvir plus ribavirin group discontinued treatment because of adverse events. The most common adverse events were nasopharyngitis (50 [29·2%] of 171), headache (12 [7·0%] of 171), and malaise (nine [5·3%] of 171) in patients receiving ledipasvir-sofosbuvir; and nasopharyngitis (40 [23·5%] of 170), anaemia (23 [13·5%] of 170), and headache in those receiving ledipasvir-sofosbuvir and ribavirin (15 [8·8%] of 170). INTERPRETATION Although existing regimens for the treatment of hepatitis C virus are effective for many patients, medical needs remain unmet, particularly in Japan where the population with hepatitis C virus genotype 1 is generally older and treatment-experienced, with advanced liver disease. The efficacy, tolerability, and absence of drug-drug interactions of ledipasvir-sofosbuvir suggest that it could be an important option for treatment of genotype 1 hepatitis C virus in Japanese patients. FUNDING Gilead Sciences.
Hepatology | 2015
K. Rajender Reddy; Marc Bourlière; Mark S. Sulkowski; Masao Omata; Stefan Zeuzem; Jordan J. Feld; Eric Lawitz; Patrick Marcellin; Tania M. Welzel; Robert H. Hyland; Xiao Ding; Jenny C. Yang; Steven J. Knox; Phillip S. Pang; Hadas Dvory-Sobol; G. Mani Subramanian; William T. Symonds; John G. McHutchison; Alessandra Mangia; Edward Gane; Masashi Mizokami; Stanislas Pol; Nezam H. Afdhal
Patients with hepatitis C virus (HCV) infection and cirrhosis are underrepresented in clinical trials of interferon‐free regimens of direct‐acting antiviral agents, making it difficult to optimize therapy. We performed a post‐hoc analysis of data from seven clinical trials to evaluate the efficacy and safety of the fixed‐dose combination of ledipasvir (LDV) and sofosbuvir (SOF), with and without ribavirin (RBV), in 513 treatment‐naïve and previously treated patients with genotype 1 HCV and compensated cirrhosis. All patients received LDV‐SOF for 12 or 24 weeks with or without RBV. We determined the rates of sustained virological response (SVR) 12 weeks after treatment (SVR12) overall and for subgroups. Of the 513 patients analyzed, 69% were previously treated and 47% had failed previous treatment with a protease‐inhibitor regimen. Overall, 493 patients (96%; 95% confidence interval [CI]: 94%‐98%) achieved SVR12, 98% of treatment‐naïve and 95% of previously treated patients. SVR12 rates did not vary greatly by treatment duration (95% of patients receiving 12 weeks and 98% of patients receiving 24 weeks of treatment), nor by addition of RBV (95% of patients receiving LDV‐SOF alone and 97% of those who received LDV‐SOF plus RBV), although previously treated patients receiving 12 weeks of LDV‐SOF without RBV had an SVR12 rate of 90%. One patient discontinued LDV‐SOF because of an adverse event (AE). The most common AEs were headache (23%), fatigue (16%‐19%), and asthenia (14%‐16%). One patient (<1%) of those receiving LDV‐SOF alone, and 4 (2%) of those receiving LDV‐SOF plus RBV had treatment‐related serious AEs. Conclusions: This analysis suggests that 12 weeks of LDV‐SOF is safe and effective for treatment‐naïve patients with HCV genotype 1 and compensated cirrhosis. The relatively lower SVR in treatment‐experienced patients treated with 12 weeks of LDV‐SOF raises the question of whether these patients would benefit from adding RBV or extending treatment duration to 24 weeks. (Hepatology 2015;62:79‐86)
Journal of Viral Hepatitis | 2014
Masao Omata; Shuhei Nishiguchi; Yoshiyuki Ueno; Hitoshi Mochizuki; Namiki Izumi; Fusao Ikeda; Hidenori Toyoda; Osamu Yokosuka; Kazushige Nirei; Takuya Genda; Takeji Umemura; Tetsuo Takehara; Naoya Sakamoto; Yoichi Nishigaki; Kunio Nakane; Nobuo Toda; Tatsuya Ide; Mikio Yanase; Keisuke Hino; Bing Gao; Kimberly L. Garrison; Hadas Dvory-Sobol; Akinobu Ishizaki; Masa Omote; Diana M. Brainard; Steven J. Knox; William T. Symonds; John G. McHutchison; Hiroshi Yatsuhashi; Masashi Mizokami
Genotype 2 hepatitis C virus (HCV) accounts for up to 30% of chronic HCV infections in Japan. The standard of care for patients with genotype 2 HCV – peginterferon and ribavirin for 24 weeks – is poorly tolerated, especially among older patients and those with advanced liver disease. We conducted a phase 3, open‐label study to assess the efficacy and safety of an all‐oral combination of the NS5B polymerase inhibitor sofosbuvir and ribavirin in patients with chronic genotype 2 HCV infection in Japan. We enrolled 90 treatment‐naïve and 63 previously treated patients at 20 sites in Japan. All patients received sofosbuvir 400 mg plus ribavirin (weight‐based dosing) for 12 weeks. The primary endpoint was sustained virologic response at 12 weeks after therapy (SVR12). Of the 153 patients enrolled and treated, 60% had HCV genotype 2a, 11% had cirrhosis, and 22% were over the aged 65 or older. Overall, 148 patients (97%) achieved SVR12. Of the 90 treatment‐naïve patients, 88 (98%) achieved SVR12, and of the 63 previously treated patients, 60 (95%) achieved SVR12. The rate of SVR12 was 94% in patients with cirrhosis and in those aged 65 and older. No patients discontinued study treatment due to adverse events. The most common adverse events were nasopharyngitis, anaemia and headache. Twelve weeks of sofosbuvir and ribavirin resulted in high rates of SVR12 in treatment‐naïve and previously treated patients with chronic genotype 2 HCV infection. The treatment was safe and well tolerated by patients, including the elderly and those with cirrhosis.
Hepatology | 2012
Stefan Zeuzem; Peter Buggisch; Kosh Agarwal; Patrick Marcellin; Daniel Sereni; Hartwig Klinker; Christophe Moreno; Jean-Pierre Zarski; Yves Horsmans; Hongmei Mo; Sarah Arterburn; Steven J. Knox; David Oldach; John G. McHutchison; Michael P. Manns; Graham R. Foster
Tegobuvir (GS‐9190), a non‐nucleoside nonstructural protein (NS)5B polymerase inhibitor, and GS‐9256, an NS3 serine protease inhibitor, individually have activity against hepatitis C virus (HCV) genotype 1. The antiviral activity of tegobuvir and GS‐9256 as oral combination therapy, or together with ribavirin (RBV) or pegylated interferon (Peg‐IFN) alpha‐2a and RBV, was assessed in a phase II, randomized, open‐label trial. Treatment‐naïve patients with genotype 1 HCV were assigned 28 days of tegobuvir 40 mg twice‐daily (BID) and GS‐9256 75 mg BID (n = 16), tegobuvir and GS‐9256 plus RBV 1,000‐1,200 mg daily (n = 15), or tegobuvir and GS‐9256 plus Peg‐IFN alpha‐2a (180 μg once‐weekly)/RBV (n = 15). The primary efficacy endpoint was rapid virologic response (RVR), with HCV RNA <25 IU/mL at day 28. After 28 days, all patients received Peg‐IFN/RBV. All patients with viral rebound or nonresponse, defined as >0.5‐log10 increase in HCV RNA from nadir or <2‐log decrease at day 5, initiated Peg‐IFN/RBV immediately. Median maximal reductions in HCV RNA were −4.1 log10 IU/mL for tegobuvir/GS‐9256, −5.1 log10 IU/mL for tegobuvir/GS‐9256/RBV, and −5.7 log10 IU/mL for tegobuvir/9256/Peg‐IFN/RBV. RVR was observed in 7% (1 of 15) of patients receiving tegobuvir/GS‐9256, 38% (5 of 13) receiving tegobuvir/GS‐9256/RBV, and 100% (14 of 14) receiving tegobuvir/9256/PEG‐IFN/RBV. The addition of Peg‐IFN/RBV at day 28 or earlier resulted in HCV RNA <25 IU/mL at week 24 in 67% (10 of 15), 100% (13 of 13), and 94% (13 of 14) of patients in the three treatment groups. Transient elevations in serum bilirubin occurred in all treatment groups. Conclusion: In genotype 1 HCV, adding RBV or RBV with Peg‐IFN provides additive antiviral activity to combination therapy with tegobuvir and GS‐9256. (HEPATOLOGY 2012)
Journal of Hepatology | 2015
Peter Ruane; Dani Ain; Richard Stryker; Raymond Meshrekey; Mina Soliman; Peter R. Wolfe; Joseph Riad; Sameh Mikhail; Kathryn Kersey; Deyuan Jiang; Benedetta Massetto; Brian Doehle; Brian J. Kirby; Steven J. Knox; John G. McHutchison; William T. Symonds
BACKGROUND & AIMS We conducted an open-label phase 2 study to assess the efficacy and safety of the oral nucleotide polymerase inhibitor sofosbuvir in combination with ribavirin in patients of Egyptian ancestry, chronically infected with genotype 4 hepatitis C virus (HCV). METHODS Treatment-naive and previously treated patients with genotype 4 HCV were randomly allocated in a 1:1 ratio to receive sofosbuvir 400mg and weight-based ribavirin, for 12 or 24 weeks. The primary efficacy endpoint was the proportion of patients with sustained virologic response (HCV RNA <25IU/ml) 12 weeks after cessation of therapy (SVR12). RESULTS Thirty treatment-naive and thirty previously treated patients were enrolled and treated for 12 weeks (n=31) or 24 weeks (n=29). Overall, 23% of patients had cirrhosis and 38% had diabetes. 14% of treatment-naive patients were interferon ineligible and 63% of treatment-experienced patients had prior non-response. SVR12 was achieved by 68% of patients (95% CI, 49-83%) in the 12-week group, and by 93% of patients (95% CI, 77-99%) in the 24-week group. The most common adverse events were headache, insomnia, and fatigue. No patient discontinued treatment due to an adverse event. CONCLUSIONS The findings from the present study suggest that 24 weeks of sofosbuvir plus ribavirin is an efficacious and well tolerated treatment in patients with HCV genotype 4 infection.
Journal of Hepatology | 2015
Wahid Doss; Gamal Shiha; Mohamed Hassany; Reham Soliman; Rabab Fouad; Marwa Khairy; Waleed Samir; Radi Hammad; Kathryn Kersey; Deyuan Jiang; Brian Doehle; Steven J. Knox; Benedetta Massetto; John G. McHutchison; Gamal Esmat
BACKGROUND & AIMS Egypt has the highest prevalence of chronic hepatitis C virus (HCV) infection in the world, and more than 90% of patients are infected with genotype 4 virus. We evaluated the efficacy and safety of the HCV polymerase inhibitor sofosbuvir in combination with ribavirin in HCV genotype 4 patients in Egypt. METHODS Treatment-naïve or treatment-experienced patients with genotype 4 HCV infection (n=103) were randomly assigned to receive either 12 or 24 weeks of sofosbuvir 400 mg and ribavirin 1000-1200 mg daily. Randomization was stratified by prior treatment experience and by presence or absence of cirrhosis. The primary endpoint was the percentage of patients with HCV RNA <25 IU/ml 12 weeks after therapy (SVR12). RESULTS Among all patients, 52% had received prior HCV treatment and 17% had cirrhosis at baseline. SVR12 rates were 90% (46/51) with 24 weeks and 77% (40/52) with 12 weeks of sofosbuvir and ribavirin therapy. Patients with cirrhosis at baseline had lower rates of SVR12 (63% 12 weeks, 78% 24 weeks) than those without cirrhosis (80% 12 weeks, 93% 24 weeks). The most common adverse events were fatigue, headache, insomnia, and anemia. Two patients experienced serious adverse events (cerebral ischemia, dyspnea). No adverse events resulted in treatment discontinuation. CONCLUSION Sofosbuvir plus ribavirin for 12 or 24 weeks is effective in treating both treatment-naïve and treatment-experienced Egyptian patients with genotype 4 HCV.
Journal of Hepatology | 2017
Stefan Zeuzem; Masashi Mizokami; Stephen Pianko; Alessandra Mangia; Kwang Hyub Han; Ross Martin; Evguenia Svarovskaia; Hadas Dvory-Sobol; Brian Doehle; Charlotte Hedskog; Chohee Yun; Diana M. Brainard; Steven J. Knox; John G. McHutchison; M.D. Miller; Hongmei Mo; Wan Long Chuang; Ira M. Jacobson; Gregory J. Dore; Mark S. Sulkowski
BACKGROUND & AIMS The efficacy of NS5A inhibitors for the treatment of patients chronically infected with hepatitis C virus (HCV) can be affected by the presence of NS5A resistance-associated substitutions (RASs). We analyzed data from 35 phase I, II, and III studies in 22 countries to determine the pretreatment prevalence of various NS5A RASs, and their effect on outcomes of treatment with ledipasvir-sofosbuvir in patients with genotype 1 HCV. METHODS NS5A gene deep sequencing analysis was performed on samples from 5397 patients in Gilead clinical trials. The effect of baseline RASs on sustained virologic response (SVR) rates was assessed in the 1765 patients treated with regimens containing ledipasvir-sofosbuvir. RESULTS Using a 15% cut-off, pretreatment NS5A and ledipasvir-specific RASs were detected in 13% and 8% of genotype 1a patients, respectively, and in 18% and 16% of patients with genotype 1b. Among genotype 1a treatment-naïve patients, SVR rates were 91% (42/46) vs. 99% (539/546) for those with and without ledipasvir-specific RASs, respectively. Among treatment-experienced genotype 1a patients, SVR rates were 76% (22/29) vs. 97% (409/420) for those with and without ledipasvir-specific RASs, respectively. Among treatment-naïve genotype 1b patients, SVR rates were 99% for both those with and without ledipasvir-specific RASs (71/72 vs. 331/334), and among treatment-experienced genotype 1b patients, SVR rates were 89% (41/46) vs. 98% (267/272) for those with and without ledipasvir-specific RASs, respectively. CONCLUSIONS Pretreatment ledipasvir-specific RASs that were present in 8-16% of patients have an impact on treatment outcome in some patient groups, particularly treatment-experienced patients with genotype 1a HCV. LAY SUMMARY The efficacy of treatments using NS5A inhibitors for patients with chronic hepatitis C virus (HCV) infection can be affected by the presence of NS5A resistance-associated substitutions (RASs). We reviewed results from 35 clinical trials where patients with genotype 1 HCV infection received treatments that included ledipasvir-sofosbuvir to determine how prevalent NS5A RASs are in patients at baseline, and found that ledipasvir-specific RASs were present in 8-16% of patients prior to treatment and had a negative impact on treatment outcome in subset of patient groups, particularly treatment-experienced patients with genotype 1a HCV.
Hepatology | 2016
Armand Abergel; Sophie Metivier; Didier Samuel; Deyuan Jiang; Kathryn Kersey; Phillip S. Pang; Evguenia Svarovskaia; Steven J. Knox; V. Loustaud-Ratti; Tarik Asselah
Genotype 4 hepatitis C virus (HCV) was considered difficult to treat in the era of pegylated interferon‐alpha (Peg‐IFN‐α) and ribavirin regimens. We evaluated the efficacy and safety of therapy with the nonstructural (NS) 5A inhibitor, ledipasvir, combined with the NS5B polymerase inhibitor, sofosbuvir, in patients with HCV genotype 4. In this phase 2, open‐label study, 44 patients (22 treatment naïve and 22 treatment experienced) received a fixed‐dose combination tablet of 90 mg of ledipasvir and 400 mg of sofosbuvir orally once‐daily for 12 weeks. The primary endpoint was the percentage of patients with HCV RNA <15 IU/mL 12 weeks after stopping therapy (SVR12). Among study participants, HCV genotype 4 subtypes were well represented (4a, n = 25; 4d, n = 10; other subtypes, n = 9). Ten patients (23%) had compensated cirrhosis. Of the 22 treatment‐experienced patients, 21 (95%) had a non‐CC IL‐28B genotype. All 44 patients completed the full 12 weeks of dosing. The SVR12 rate was 93% (41 of 44; 95% confidence interval, 81‐99). SVR12 rates were similar between treatment‐naïve (95%; 21 of 22) and treatment‐experienced (91%; 20 of 22) patients. All 3 patients who did not achieve SVR12 had virological relapse within 4 weeks of the end of treatment; all 3 had baseline HCV RNA ≥800,000 IU/mL, a non‐CC IL‐28B genotype, and pretreatment NS5A resistance‐associated variants. None of the patients who relapsed had cirrhosis. The most common adverse events were asthenia, headache, and fatigue. No patients experienced a serious adverse event. Conclusion: The all‐oral regimen of ledipasvir and sofosbuvir is an effective and safe treatment for a wide range of HCV 4 subtypes in both treatment‐naïve and ‐experienced patients, including those with compensated cirrhosis. (EudraCT number: 2013‐003978‐27; Clinicaltrials.gov NCT02081079) (Hepatology 2016;64:1049‐1056)
Hepatology | 2016
Sammy Saab; Sarah H. Park; Masashi Mizokami; Masao Omata; Alessandra Mangia; Ed Eggleton; Yanni Zhu; Steven J. Knox; Phil Pang; M. Subramanian; Kris V. Kowdley; Nezam H. Afdhal
Elderly subjects have been historically underrepresented in clinical trials involving antiviral hepatitis C therapies. The aim of this analysis was to retrospectively evaluate the safety and efficacy of ledipasvir/sofosbuvir (LDV/SOF) by age groups of <65 years versus ≥65 years among subjects enrolled in phase 3 trials. Four open‐label phase 3 clinical trials evaluated the safety and efficacy of LDV/SOF with or without ribavirin (RBV) for the treatment of genotype 1 chronic hepatitis C virus. Sustained virological response at 12 weeks, treatment‐emergent adverse events (AEs), and graded laboratory abnormalities were analyzed according to age group. Of the 2293 subjects enrolled in four phase 3 trials, 264 (12%) were ≥65 years of age, of whom 24 were aged ≥75 years. Sustained virological response at 12 weeks was achieved by 97% (1965/2029) of subjects aged <65 years and 98% (258/264) of subjects aged ≥65 years. The most common AEs in both LDV/SOF groups that occurred in ≥10% of subjects were headache and fatigue. The rate of study discontinuation due to AEs was similar in the two age cohorts. The use of RBV in 1042 (45%) subjects increased the number of AEs, treatment‐related AEs, and AEs leading to study drug modification/interruption, particularly among elderly subjects. Conclusions: LDV/SOF with or without RBV was highly effective for treatment of genotype 1 chronic hepatitis C virusin subjects aged 65 and older. Addition of RBV did not increase sustained virological response at 12 weeks rates but led to higher rates of AEs, especially in elderly subjects. (Hepatology 2016;63:1112–1119)
Journal of Viral Hepatitis | 2016
Masashi Mizokami; Hadas Dvory-Sobol; Namiki Izumi; Shuhei Nishiguchi; B. Doehle; E. S. Svarovskaia; S. De-Oertel; Steven J. Knox; Diana M. Brainard; M. D. Miller; Hongmei Mo; Naoya Sakamoto; Tetsuo Takehara; Masao Omata
High rates of sustained virologic response (SVR) has been achieved in Japanese patients with chronic hepatitis C virus (HCV) genotype (GT)1 and GT2 infection treated with ledipasvir/sofosbuvir (LDV/SOF) ±ribavirin (RBV) and SOF+RBV, respectively. We evaluated the effect of baseline HCV NS5A and NS5B resistance‐associated variants (RAVs) on treatment outcome and characterized variants at virologic failure.