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Featured researches published by Stephen J. Rossi.


The American Journal of Gastroenterology | 2005

Prospective multicenter study of eligibility for antiviral therapy among 4,084 U.S. veterans with chronic hepatitis C virus infection

Edmund J. Bini; Norbert Bräu; Sue Currie; Hui Shen; Anand Bs; Ke-Qin Hu; Lennox J. Jeffers; Samuel B. Ho; David Johnson; Warren N. Schmidt; Paul D. King; Ramsey Cheung; Timothy R. Morgan; Joseph A. Awad; Marcos Pedrosa; Kyong-Mi Chang; Ayse Aytaman; Franz Simon; Curt Hagedorn; Richard H. Moseley; Jawad Ahmad; Charles L. Mendenhall; Bradford Waters; Doris B. Strader; Anna W. Sasaki; Stephen J. Rossi; Teresa L. Wright

BACKGROUND:Many veterans may not be candidates for hepatitis C virus (HCV) treatment due to contraindications to therapy. The aims of this study were to determine the proportion of HCV-infected veterans who were eligible for interferon alfa and ribavirin therapy and to evaluate barriers to HCV treatment.METHODS:We prospectively enrolled 4,084 veterans who were referred for HCV treatment over a 1-yr period at 24 Veterans Affairs (VA) Medical Centers. Treatment candidacy was assessed using standardized criteria and the opinion of the treating clinician.RESULTS:Overall, 32.2% (95% CI, 30.8–33.7%) were candidates for HCV treatment according to standardized criteria, whereas 40.7% (95% CI, 39.2–42.3%) were candidates in the opinion of the treating clinician. Multivariable analysis identified ongoing substance abuse (OR = 17.68; 95% CI, 12.24–25.53), comorbid medical disease (OR = 9.62; 95% CI, 6.85–13.50), psychiatric disease (OR = 9.45; 95% CI, 6.70–13.32), and advanced liver disease (OR = 8.43; 95% CI, 4.42–16.06) as the strongest predictors of not being a treatment candidate. Among patients who were considered treatment candidates, 76.2% (95% CI, 74.0–78.3%) agreed to be treated and multivariable analysis showed that persons ≥50 yr of age (OR = 1.37; 95% CI, 1.07–1.76) and those with >50 lifetime sexual partners (OR = 1.44; 95% CI, 1.08–1.93) were more likely to decline treatment.CONCLUSIONS:The majority of veteran patients are not suitable candidates for HCV treatment because of substance abuse, psychiatric disease, and comorbid medical disease, and many who are candidates decline therapy. Multidisciplinary collaboration is needed to overcome barriers to HCV therapy in this population.


Gastroenterology | 2011

The combination of ribavirin and peginterferon is superior to peginterferon and placebo for children and adolescents with chronic hepatitis C

Kathleen B. Schwarz; Regino P. Gonzalez-Peralta; Karen F. Murray; Jean P. Molleston; Barbara Haber; Maureen M. Jonas; Philip J. Rosenthal; Parvathi Mohan; William F. Balistreri; Michael R. Narkewicz; Lesley J. Smith; Steven J. Lobritto; Stephen J. Rossi; Alexandra Valsamakis; Zachary D. Goodman; Patricia R. Robuck; Bruce A. Barton

BACKGROUND & AIMS Although randomized trials of adults infected with hepatitis C virus (HCV) have shown that ribavirin increases the efficacy of pegylated interferon (PEG), such trials have not been performed in children. We conducted a randomized controlled trial of PEG and ribavirin, compared with PEG and placebo, in children 5 to 17 years old with chronic hepatitis C. METHODS HCV RNA-positive children from 11 university medical centers were randomly assigned to receive either PEG alfa-2a (PEG-2a; 180 μg/1.73 m(2) body surface area, subcutaneously each week; n = 55) and ribavirin (15 mg/kg orally in 2 doses daily) or PEG-2a and placebo (n = 59) for 48 weeks. The primary end point was sustained virologic response (SVR; lack of detectable HCV RNA at least 24 weeks after stopping therapy). RESULTS SVR was achieved in 53% of children treated with PEG-2a and ribavirin, compared with 21% of children who received PEG-2a and placebo (P < .001). Early virologic response (HCV RNA reduction >2 log(10) IU at 12 weeks) had a negative predictive value of only 0.89 in children with genotype 1, indicating that these children might benefit from 24 weeks of therapy before stopping treatment. Side effects, especially neutropenia, led to dose modification in 40% of children. Eighty-two percent of the PEG/ribavirin and 86% of the PEG/placebo group were in compliance with the year 2 follow-up visit; the durability of virologic response was 100% in both groups. CONCLUSIONS The combination of PEG and ribavirin is superior to PEG and placebo as therapy for chronic hepatitis C in children and adolescents.


Hepatology | 2016

Engineered fibroblast growth factor 19 reduces liver injury and resolves sclerosing cholangitis in Mdr2-deficient mice

Mei Zhou; R. Marc Learned; Stephen J. Rossi; Alex M. DePaoli; Hui Tian; Lei Ling

Defects in multidrug resistance 3 gene (MDR3), which encodes the canalicular phospholipid flippase, cause a wide spectrum of cholangiopathy phenotypes in humans. Mice deficient in Mdr2 (murine ortholog of MDR3) develop liver diseases that closely reproduce the biochemical, histological, and clinical features of human cholangiopathies such as progressive familial intrahepatic cholestasis and primary sclerosing cholangitis. We hypothesized that modulating bile acid metabolism by the gut hormone fibroblast growth factor 19 (FGF19) may represent a novel approach for treating cholangiopathy and comorbidities. We introduced adeno‐associated virus carrying the gene for either the endocrine hormone FGF19 or engineered FGF19 variant M70 to 12‐week old Mdr2‐deficient mice with fully established disease. Effects on serum levels of liver enzymes, liver histology, and bile acid homeostasis were evaluated. FGF19 and M70 rapidly and effectively reversed liver injury, decreased hepatic inflammation, attenuated biliary fibrosis, and reduced cholecystolithiasis in Mdr2‐deficient mice. Mechanistically, FGF19 and M70 significantly inhibited hepatic expression of Cyp7a1 and Cyp27a1, which encode enzymes responsible for the rate‐limiting steps in the classic and alternate bile acid synthetic pathways, thereby reducing the hepatic bile acid pool and blood levels of bile acids. Importantly, prolonged exposure to FGF19, but not M70, led to the formation of hepatocellular carcinomas in the Mdr2‐deficient mice. Furthermore, M70 ameliorated the hepatosplenomegaly and ductular proliferation that are associated with cholangiopathy. Conclusion: These results demonstrate the potential for treating cholangiopathy by safely harnessing FGF19 biology to suppress bile acid synthesis. (Hepatology 2016;63:914–929)


Journal of Viral Hepatitis | 2006

Black patients with chronic hepatitis C have a lower sustained viral response rate than non-Blacks with genotype 1, but the same with genotypes 2/3, and this is not explained by more frequent dose reductions of interferon and ribavirin*.

Norbert Bräu; Edmund J. Bini; S. Currie; Hui Shen; Warren N. Schmidt; Paul D. King; Samuel B. Ho; Ramsey Cheung; Ke-Qin Hu; Anand Bs; Franz Simon; Ayse Aytaman; D. P. Johnson; Joseph A. Awad; Jawad Ahmad; Charles L. Mendenhall; Marcos Pedrosa; Richard H. Moseley; C. H. Hagedorn; Bradford Waters; Kyong-Mi Chang; Timothy R. Morgan; Stephen J. Rossi; Lennox J. Jeffers; Teresa L. Wright

Summary.  In previous hepatitis C virus (HCV) treatment studies, Black patients not only had a lower sustained viral response (SVR) rate to interferon and ribavirin (RBV) than non‐Black patients but also a higher frequency of HCV genotype 1 (GT‐1) infection. The aim of this community‐based study was to determine whether Black patients have a lower SVR rate independent of genotype. We prospectively enrolled 785 patients (24.8% Black, 71.5% White, 3.7% others) who received interferon alpha‐2b 3 MU three times weekly + RBV 1000–1200 mg/day for 24 weeks (GT‐2/3) or 48 weeks (GT‐1). Black patients were more commonly infected with GT‐1 (86.8%vs 64.8%, P < 0.001) and less frequently had an SVR compared with non‐Black patients (8.4%vs 21.6%, P < 0.001). Within GT‐1, Black patients had a lower SVR rate than non‐Black patients (6.1%vs 14.1%, P = 0.004) but not within GT‐2/3 (50.0%vs 36.5%, P = 0.47). Black patients had lower baseline haemoglobin levels (14.8 vs 15.3 g/dL, P < 0.001) and neutrophil counts (2900 vs 4100/mm3, P < 0.001) and required more frequent dose reductions of RBV (29.8%vs 18.5%, P < 0.001) and interferon (4.7%vs 1.6%, P = 0.012). However, dose reductions were not associated with lower SVR rates while early treatment discontinuations were (2.9%vs 25.7%, P < 0.001). Independent predictors of SVR were GT‐1 [odds ratio (OR) 0.33; 95% confidence interval (CI) 0.20–0.55; P < 0.001], Black race (OR 0.45; 95% CI 0.22–0.93; P = 0.030), and advanced fibrosis, stages 3 + 4 (OR 0.53; 95% CI 0.31–0.92; P = 0.023). In conclusion, Black patients infected with HCV GT‐1 (but not GT‐2/3) have a lower SVR rate than non‐Black patients. This is not explained by their lower baseline haemoglobin levels and neutrophil counts that lead to higher rates of ribavirin and interferon dose reductions.


The American Journal of Gastroenterology | 2008

Efficacy and safety of peginterferon alfa-2a/ribavirin in methadone maintenance patients: randomized comparison of direct observed therapy and self-administration.

Herbert L. Bonkovsky; Alan D. Tice; Rockford G. Yapp; Henry C. Bodenheimer; Alexander Monto; Stephen J. Rossi; Mark S. Sulkowski

BACKGROUND: Adherence to chronic hepatitis C (CHC) treatment may be particularly challenging in methadone maintenance patients. We assessed the safety, tolerability, and efficacy of peginterferon alfa-2a/ribavirin treatment in methadone maintenance patients previously untreated for CHC.METHODS: Patients were randomized 1:1 to direct observed therapy (DOT) or self-administration (SA) of peginterferon alfa-2a. DOT patients were seen weekly at methadone clinics; SA patients were seen less frequently, only at investigative sites. Genotype 1-infected patients were treated for 48 wk with peginterferon alfa-2a (180 μg/wk)/ribavirin (1,000/1,200 mg/day); genotypes 2- and 3-infected patients were treated for 24 wk with peginterferon alfa-2a (180 μg/wk)/ribavirin (800 mg/day).RESULTS: Based on defined efficacy stopping rules, 77% (37/48) completed their targeted length of treatment, and 44% (21/48) achieved sustained virologic response (SVR). Two DOT and 3 SA patients were withdrawn for safety reasons and 6 and 9, respectively, for nonsafety reasons. Over 60% and 50% of each group were >80% compliant with the planned cumulative doses of peginterferon alfa-2a and ribavirin, respectively, and over 60% with overall treatment duration. SVR rates were 54% (13/24) for DOT and 33% (8/24) for SA; 23% (3/13) and 38% (6/16), respectively, for genotype 1 and 91% (10/11) and 25% (2/8), respectively, for genotypes 2 and 3. Stepwise logistic regression analysis, showed that DOT (vs SA; OR 3.27, 95% CI 0.90–11.91, P= 0.073) and Caucasian race (vs Other; OR 13.31, 95% CI 1.42–124.71, P= 0.023) were predictors of SVR.CONCLUSION: Peginterferon alfa-2a/ribavirin can be used safely and successfully in CHC patients receiving methadone maintenance.


The Lancet | 2018

NGM282 for treatment of non-alcoholic steatohepatitis: a multicentre, randomised, double-blind, placebo-controlled, phase 2 trial

Stephen A. Harrison; Mary E. Rinella; Manal F. Abdelmalek; James F. Trotter; Angelo H. Paredes; Hays Arnold; Marcelo Kugelmas; Mustafa R. Bashir; Mark J Jaros; Lei Ling; Stephen J. Rossi; Alex M. DePaoli; Rohit Loomba

BACKGROUND Non-alcoholic steatohepatitis is a chronic liver disease characterised by the presence of hepatic steatosis, inflammation, and hepatocellular injury, for which no Food and Drug Administration (FDA)-approved treatment exists. FGF19 is a hormone that regulates bile acid synthesis and glucose homoeostasis. We aimed to assess the safety and efficacy of NGM282, an engineered FGF19 analogue, for the treatment of non-alcoholic steatohepatitis. METHODS In this randomised, double-blind, placebo-controlled, phase 2 study, we recruited patients aged 18-75 years with biopsy-confirmed non-alcoholic steatohepatitis as defined by the non-alcoholic steatohepatitis clinical research network histological scoring system, from hospitals and gastroenterology and liver clinics in Australia and the USA. Key eligibility criteria included a non-alcoholic fatty liver disease activity score of 4 or higher, stage 1-3 fibrosis, and at least 8% liver fat content. Patients were randomly assigned (1:1:1) via a web-based system and stratified by diabetic status to receive either 3 mg or 6 mg subcutaneous NGM282 or placebo. The primary endpoint was the absolute change from baseline to week 12 in liver fat content. Responders were patients who achieved a 5% or larger reduction in absolute liver fat content as measured by MRI-proton density fat fraction. Efficacy analysis was by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT02443116. FINDINGS Between July 14, 2015, and Aug 30, 2016, 166 patients were screened across 18 sites in Australia and the USA. 82 patients were randomly assigned to receive 3 mg NGM282 (n=27), 6 mg NGM282 (n=28), or placebo (n=27). At 12 weeks, 20 (74%) patients in the 3 mg dose group and 22 (79%) in the 6 mg dose group achieved at least a 5% reduction in absolute liver fat content from baseline (relative risk 10·0 [95% CI 2·6-38·7] vs 11·4 [3·0-43·8], respectively; p<0·0001 for both comparisons) versus two (7%) in the placebo group. Overall, 76 (93%) of 82 patients experienced at least one adverse event, most of which were grade 1 (55 [67%]), and only five (6%) were grade 3 or worse. The most commonly (≥10%) reported adverse events were injection site reactions (28 [34%]), diarrhoea (27 [33%]), abdominal pain (15 [18%]), and nausea (14 [17%]). These adverse events were reported more frequently in the NGM282 groups compared with the placebo group. No life-threatening events or patient deaths occurred during the study. INTERPRETATION NGM282 produced rapid and significant reductions in liver fat content with an acceptable safety profile in patients with non-alcoholic steatohepatitis. Further study of NGM282 is warranted in this patient population. FUNDING NGM Biopharmaceuticals.


Hepatology Communications | 2017

Engineered FGF19 eliminates bile acid toxicity and lipotoxicity leading to resolution of steatohepatitis and fibrosis in mice

Mei Zhou; R. Marc Learned; Stephen J. Rossi; Alex M. DePaoli; Hui Tian; Lei Ling

Nonalcoholic fatty liver disease (NAFLD) is an increasingly prevalent chronic liver disease for which no approved therapies are available. Despite intensive research, the cellular mechanisms that mediate NAFLD pathogenesis and progression are poorly understood. Although obesity, diabetes, insulin resistance, and related metabolic syndrome, all consequences of a Western diet lifestyle, are well‐recognized risk factors for NAFLD development, dysregulated bile acid metabolism is emerging as a novel mechanism contributing to NAFLD pathogenesis. Notably, NAFLD patients exhibit a deficiency in fibroblast growth factor 19 (FGF19), an endocrine hormone in the gut–liver axis that controls de novo bile acid synthesis, lipogenesis, and energy homeostasis. Using a mouse model that reproduces the clinical progression of human NAFLD, including the development of simple steatosis, nonalcoholic steatohepatitis (NASH), and advanced “burnt‐out” NASH with hepatocellular carcinoma, we demonstrate that FGF19 as well as an engineered nontumorigenic FGF19 analogue, M70, ameliorate bile acid toxicity and lipotoxicity to restore liver health. Mass spectrometry‐based lipidomics analysis of livers from mice treated with FGF19 or M70 revealed significant reductions in the levels of toxic lipid species (i.e., diacylglycerols, ceramides and free cholesterol) and an increase in levels of unoxidized cardiolipins, an important component of the inner mitochondrial membrane. Furthermore, treatment with FGF19 or M70 rapidly and profoundly reduced levels of liver enzymes, resolved the histologic features of NASH, and enhanced insulin sensitivity, energy homeostasis, and lipid metabolism. Whereas FGF19 induced hepatocellular carcinoma formation following prolonged exposure in these mice, animals expressing M70 showed no evidence of liver tumorigenesis in this model. Conclusion: We have engineered an FGF19 hormone that is capable of regulating multiple pathways to deliver antisteatotic, anti‐inflammatory, and antifibrotic activities and that represents a potentially promising therapeutic for patients with NASH. (Hepatology Communications 2017;1:1024–1042)


Gastroenterology | 2017

Baseline Parameters in Clinical Trials for Nonalcoholic Steatohepatitis: Recommendations From the Liver Forum

Yuval A. Patel; Joanne C. Imperial; Andrew J. Muir; Quentin M. Anstee; David DeBrota; Lara Dimick‐Santos; Claudia Filozof; Ruby Mehta; A. Sanyal; Elmer Schabel; Brent A. Neuschwander-Tetri; Veronica Miller; Sander J. Bangma; Melanie Baxter; Sherif Boulos; Gary Burgess; Manu Chakravarthy; Rose Christian; Anthony Coombs; Goran Gannedahl; Richard Herrmann; Dw Hum; Joanne Imperial; Stuart Kendrick; L. Macconell; Sophie Megnien; Yuval Patel; Dan Peres; Stephen J. Rossi; Arun J. Sanyal

Nonalcoholic fatty liver disease (NAFLD) is the most prevalent form of chronic liver disease worldwide and is an increasing cause of liver-related morbidity and mortality. Nonalcoholic steatohepatitis (NASH), the progressive histological subtype of the disease, is a growing target for drug design and development. Currently, no effective drug therapies exist for the management of NASH and multiple challenges exist for NASH-related clinical trials, stressing the need for a focused deliberative approach to facilitate drug development. One such challenge includes the inconsistent measurement of baseline parameters across clinical trials, which makes interpretation and comparison of trial data difficult and impedes drug development effort.


The American Journal of Gastroenterology | 2018

Effects of NGM282, an FGF19 variant, on colonic transit and bowel function in functional constipation: a randomized phase 2 trial

Ibironke Oduyebo; Michael Camilleri; Alfred D. Nelson; Disha Khemani; Sara Linker Nord; Irene Busciglio; Duane Burton; Deborah Rhoten; Michael Ryks; Paula Carlson; Leslie J. Donato; Alan J. Lueke; Kathline Kim; Stephen J. Rossi; Alan R. Zinsmeister

OBJECTIVE: NGM282 is an analog of fibroblast growth factor 19 (FGF19), a potent inhibitor of bile acid (BA) synthesis in animals and humans. In phase 2 trials in type 2 diabetes and primary biliary cholangitis, NGM282 was associated with dose‐related abdominal cramping and diarrhea. We aimed to examine effects of NGM282 on colonic transit, stool frequency and consistency, hepatic BA synthesis (fasting serum C4), fecal fat, and BA in functional constipation (FC). METHODS: Two‐dose NGM282 (1 and 6 mg, subcutaneously daily), parallel‐group, randomized, placebocontrolled, 14‐day study in patients with FC (Rome III criteria) and baseline colonic transit 24 h geometric center (GC) <3.0. We explored treatment interaction with SNPs in genes KLB, FGFR4, and TGR5 (GPBAR1). Statistical analysis: overall ANCOVA at &agr; = 0.025 (baseline as covariate where available), with three pairwise comparisons among the three groups (&agr; = 0.008). RESULTS: Overall, NGM282 altered bowel function (number of bowel movements, looser stool form, and increased ease of passage) and significantly accelerated gastric and colonic transit. Dose‐related effects were seen with GC 24 h, but not with gastric emptying (GE) and GC 48 h. There were no differences in fecal fat or weight, but there was reduced fecal total BA excretion with NGM282. The most common adverse events were increased appetite (n = 0 with placebo, 2 with 1 mg, 9 with 6 mg), injection site reaction (n = 2 placebo, 4 with 1 mg, 8 with 6 mg), and diarrhea (n = 1 with 1 mg and 4 with 6 mg NGM282). There was treatment interaction with KLB SNP, with greater increase in colonic transit in participants with the minor A allele (p = 0.056). CONCLUSION: NGM282 significantly impacts GE and colonic transit, consistent with the observed clinical symptoms. The specific mechanism of prokinetic activity requires further research.


Journal of Hepatology | 2015

P1140 : NGM282 demonstrates potent antifibrotic activity in a mouse model of severe cholestatic fibrosis

Jian Luo; B. Ko; C. To; Lei Ling; Stephen J. Rossi; Alex M. DePaoli; Hui Tian

P1139 TESTOSTERONE SUPPRESSES HEPATIC INFLAMMATION BY THE DOWN-REGULATION OF IL-17, CXCL-9 AND CXCL-10 IN A MOUSE MODEL OF EXPERIMENTAL CHOLANGITIS D. Schwinge, A. Carambia, A. Quaas, T. Krech, C. Wegscheid, G. Tiegs, I. Prinz, A.W. Lohse, J. Herkel, C. Schramm. I. Department of Medicine, University Medical Center HamburgEppendorf, I. Department of Medicine, University Medical Center Hamburg Eppendorf, Department of Pathology, Experimental Immunology and Hepatology, University Medical Center HamburgEppendorf, Hamburg, Institute of Immunology, Hannover Medical School, Hannover, I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany E-mail: [email protected]

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Ke-Qin Hu

University of California

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Norbert Bräu

Icahn School of Medicine at Mount Sinai

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Samuel B. Ho

University of California

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