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Dive into the research topics where Christopher O’Brien is active.

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Featured researches published by Christopher O’Brien.


Journal of Hepatology | 2009

Baseline characteristics and early on-treatment response predict the outcomes of 2 years of telbivudine treatment of chronic hepatitis B.

Stefan Zeuzem; Edward Gane; Yun-Fan Liaw; S.G. Lim; Adrian DiBisceglie; Maria Buti; Anuchit Chutaputti; J. Rasenack; Jinlin Hou; Christopher O’Brien; Tuan T. Nguyen; Jidong Jia; Thierry Poynard; Bruce Belanger; Weibin Bao; Nikolai V. Naoumov

BACKGROUND/AIMS In the GLOBE trial, telbivudine treatment was identified as a significant, independent predictor of better outcomes at 2 years. We analyzed all telbivudine recipients in this trial to determine the predictors of optimal outcomes. METHODS The intent-to-treat population comprised 458 HBeAg-positive and 222 HBeAg-negative telbivudine-treated patients. Multivariate logistic regression analyses were employed to evaluate baseline and/or early on-treatment variables. RESULTS Baseline HBV DNA<9 log(10)copies/mL, or ALT levels > or = 2x above normal were strong pretreatment predictors for HBeAg-positive, but not for HBeAg-negative patients. However, non-detectable serum HBV DNA at treatment week 24 (TW24) was the strongest predictor for better outcomes for both groups. A combination of pretreatment characteristics plus TW24 response identified subgroups with the best outcomes: (1) HBeAg-positive patients with baseline HBV DNA<9 log(10)copies/mL, ALT > or = 2x above normal and non-detectable HBV DNA at TW24 achieved at 2 years: non-detectable HBV DNA in 89%, HBeAg seroconversion in 52%, telbivudine resistance in 1.8%; and (2) HBeAg-negative patients with baseline HBV DNA<7 log(10)copies/mL and non-detectable serum HBV DNA at TW24 achieved at 2 years: non-detectable HBV DNA in 91%, telbivudine resistance in 2.3%. CONCLUSION During telbivudine treatment, non-detectable serum HBV DNA at treatment week 24 is the strongest predictor for optimal outcomes at 2 years.


The American Journal of Gastroenterology | 2002

Preliminary observation with dronabinol in patients with intractable pruritus secondary to cholestatic liver disease

Guy W. Neff; Christopher O’Brien; K. Rajender Reddy; Nora V. Bergasa; Arie Regev; Enrique G. Molina; Rafael Amaro; Miguel J. Rodriguez; VeEtta Chase; Lennox J. Jeffers; Eugene R. Schiff

Pruritus due to cholestatic liver disease can be particularly difficult to manage and frequently is intractable to a variety of medical therapies. The aim of our study is to evaluate the efficacy of Δ-9-tetrahydrocannabinol (Δ-9-THC) for intractable cholestatic related pruritus (ICRP) that has failed conventional (and unconventional) remedies. Three patients were evaluated for plasmapheresis because of ICRP. All 3 patients had previously been extensively treated with standard therapies for ICRP including: diphenhydramine, chlorpheniramine, cholestyramine, rifampicin, phenobarbital, doxepin, naltrexone, UV therapy, and topical lotions. Even multiple courses of plasmapheresis were performed without any benefit for the intractable pruritus. All patients reported significant decreases in their quality of life, including lack of sleep, depression, inability to work, and suicidal ideations. All patients were started on 5 mg of Δ-9-THC (Marinol) at bedtime. All 3 patients reported a decrease in pruritus, marked improvement in sleep, and eventually were able to return to work. Resolution of depression occurred in two of three. Side effects related to the drug include one patient experiencing a disturbance in coordination. Marinol dosage was decreased to 2.5 mg in this patient with resolution of symptoms. The duration of antipruritic effect is approximately 4–6 hrs in all three patients suggesting the need for more frequent dosing. Δ-9-tetrahydrocannabinol may be an effective alternative in patients with intractable cholestatic pruritus.


Gastrointestinal Endoscopy | 1999

The first case report of the use of a zoom videoendoscope for the evaluation of small bowel graft mucosa in a human after intestinal transplantation

Tomoaki Kato; Christopher O’Brien; Seigo Nishida; Hanno Hoppe; Martin Gasser; Mariana Berho; Miguel J. Rodriguez; Philip Ruiz; Andreas G. Tzakis

BACKGROUND Control of allograft rejection remains the most difficult dilemma in intestinal transplantation. Standard endoscopic surveillance to date has not been always accurate in the diagnosis of rejection. We describe the first application of a zoom video endoscope in monitoring graft mucosa in humans after intestinal transplantation. METHOD A zoom video endoscope, which can magnify the image up to 100-fold, was used in this study. The patient was a 31-year-old man who received an isolated intestinal transplant. Surveillance endoscopy with the zoom video endoscope was performed through the ileostomy. Endoscopic biopsies were done at the same time. RESULTS The zoom video endoscope showed the microscopic architecture of the graft mucosa such as villi and crypts with outstanding quality. We found that an enlargement of the crypt areas appeared to correlate with morphologic changes of early rejection. This finding was reversed with the treatment of rejection. CONCLUSIONS The zoom video endoscope successfully showed the detailed information of intestinal mucosa. The ability to visualize a more representative view of the graft mucosa could lead to better detection of early rejection. A greater experience with this unique method will provide more accurate assessment of the intestinal allograft.


Annals of Hepatology | 2016

Daclatasvir and Peginterferon/Ribavirin for Black/African-American and Latino Patients with HCV infection.

Maribel Rodriguez-Torres; Eric Lawitz; Bienvenido G. Yangco; Lennox J. Jeffers; Steven Han; Paul J. Thuluvath; Vinod Rustgi; Stephen A. Harrison; Reem Ghalib; John M. Vierling; Velimir A. Luketic; Philippe J. Zamor; Natarajan Ravendhran; Timothy R. Morgan; Brian Pearlman; Christopher O’Brien; Hicham Khallafi; Nikolaos Pyrsopoulos; George Kong; Fiona McPhee; Philip D. Yin; Eric Hughes; Michelle Treitel

BACKGROUND Patient race and ethnicity have historically impacted HCV treatment response. This phase 3 study evaluated daclatasvir with peginterferon-alfa-2a/ribavirin (pegIFN alfa-2a/RBV) in treatment-naive black/African American (AA), Latino, and white non-Latino patients with chronic HCV genotype 1 infection. MATERIAL AND METHODS In this single-arm, open-label study, 246 patients received daclatasvir plus pegIFN alfa-2a and weight-based RBV. Patients with an extended rapid virologic response (eRVR; undetectable HCV-RNA at treatment weeks 4 and 12) received 24 weeks of treatment; those without eRVR received an additional 24 weeks of treatment with pegIFN alfa-2a/RBV. The primary endpoint was sustained virologic response at post-treatment week 12 (SVR12; HCV-RNA < 25 IU/mL) compared with the cohort historical rate. RESULTS Most patients were IL28B non-CC (84.4% black/AA; 77.6% Latino) genotype 1a-infected (72.7%; 81.3%), with HCV-RNA ≥ 800,000 IU/mL (81.3%; 64.5%). SVR12 rates were 50.8% (65/128; 95% confidence interval [CI], 42.1-59.4) for black/AA and 58.9% (63/107; 95% CI, 49.6-68.2) for Latino patients. The majority (55.5%; 58.9%) received 24 weeks treatment; rapid reductions (> 4-log10) in HCV-RNA levels were observed. Only 60.9% (78/128) of black/AA and 63.6% (68/107) of Latino patients completed treatment. On-treatment serious adverse events (SAEs) occurred in 21 patients. Discontinuations due to adverse events (aEs) occurred in 9 black/AA and 6 Latino patients. CONCLUSION SVR12 rates for black/AA (50.8%) and Latino (58.9%) cohorts treated with daclatasvir plus pegIFN alfa-2a/RBV and the lower bound of the 95% Cls were higher than the estimated historical control (black/AA, 26% SVR; Latino, 36% SVR) treated with pegIFN alfa-2a/RBV. These data support daclatasvir use in all-oral direct-acting antiviral combinations.


Hepatology Communications | 2018

Randomized, Double‐Blind, Placebo‐Controlled, Single Ascending Dose Trial of Synthetic Preimplantation Factor in Autoimmune Hepatitis

Christopher O’Brien; Eytan R. Barnea; Paul Martin; Cynthia Levy; Eden Sharabi; Kalyan R. Bhamidimarri; Eric Martin; Leopold Arosemena; Eugene R. Schiff

Preimplantation factor (PIF) is an evolutionary conserved peptide secreted by viable embryos which promotes maternal tolerance without immune suppression. Synthetic PIF (sPIF) replicates native peptide activity. The aim of this study was to conduct the first‐in‐human trial of the safety, tolerability, and pharmacokinetics of sPIF in patients with autoimmune hepatitis (AIH). We performed a randomized, double‐blind, placebo‐controlled, prospective phase I clinical trial. Patients were adults with documented AIH with compensated chronic liver disease. Diagnosis of AIH was confirmed by either a pretreatment International Criteria for the Diagnosis of AIH score of 15 or more, or a posttreatment score of 17 or more. Patients were divided into three dosing cohorts (0.1, 0.5, or 1.0 mg/kg) of 6 patients in each group. Three patients in each group had normal liver tests and 3 patients had abnormal liver tests. They were randomized to receive a single, subcutaneous dose of either sPIF or a matching placebo. Eighteen patients were enrolled, and all successfully completed the trial. There were no clinically significant adverse events and all doses were well tolerated. Ascending doses of sPIF produced a linear increase in the respective serum levels with a half‐life of 90 minutes. There were no grade 2, 3 or 4 laboratory abnormalities. No patient developed detectable anti‐sPIF antibodies. Conclusion: This first‐in‐human trial of the safety and pharmacokinetics of sPIF (a novel biologic immune modulatory agent) demonstrated both excellent safety and tolerability. The data support further studies of multiple ascending doses of sPIF in autoimmune hepatitis and potentially other autoimmune disorders.


Current Hepatitis Reports | 2012

Management of patients with chronic hepatitis b before and after liver transplantation: An update

Andres F. Carrion; Paul Martin; Christopher O’Brien

The use of newer and more potent antiviral agents against hepatitis B virus (HBV) results in greater viral suppression; however, liver transplantation is still required for complications of HBV infection. Post-transplant outcomes for HBV-related disorders are currently comparable to or slightly better than for other indications for liver transplantation in adults in the United States. In the absence of prophylactic antiviral therapy, recurrent HBV infection occurs invariably in patients with detectable serum HBV-deoxyribonucleic acid (DNA) at the time of transplantation, leading to poorer outcomes with severe graft injury, reduced patient and allograft survival. Therefore, anti-HBV therapy is indicated in all patients with detectable serum HBV-DNA pre-transplantation and prophylactic therapy to prevent recurrent HBV infection is standard-of-care. This review summarizes available evidence for the use of different antiviral agents before liver transplantation, the effectiveness of prophylactic agents in preventing recurrent HBV infection post-liver transplantation, and the efficacy of several regimens for treating recurrent HBV infection post-liver transplantation.


Gastroenterology | 2004

Peginterferon alfa-2a (40 kilodaltons) and ribavirin in patients with chronic hepatitis C and normal aminotransferase levels

Stefan Zeuzem; M. Diago; Edward Gane; K. Rajender Reddy; Paul J. Pockros; Daniele Prati; Mitchell L. Shiffman; Patrizia Farci; Norman Gitlin; Christopher O’Brien; François Lamour; Pilar Lardelli


Journal of Hepatology | 2007

Virological response and safety outcomes in therapy–naïve patients treated for chronic hepatitis C with taribavirin or ribavirin in combination with pegylated interferon alfa-2a: A randomized, phase 2 study

Robert G. Gish; Sanjeev Arora; K. Rajender Reddy; David R. Nelson; Christopher O’Brien; Yi Xu; Brian Murphy


Transplantation Proceedings | 2000

Improved rejection surveillance in intestinal transplant recipients with frequent use of zoom video endoscopy

Tomoaki Kato; Christopher O’Brien; M Berho; Seigo Nishida; David Levi; Farrukh A. Khan; Antonio Daniele Pinna; Jose Nery; Phillip Ruiz; Andreas G. Tzakis


Journal of Hepatology | 2015

P0878 : First ribavirin-free sofosbuvir and simeprevir treatment of Hepatitis C genotype 1 patients with severe renal impairment (GFR <30 ml/min or dialysis)

Frank Czul; Eugene R. Schiff; Adam Peyton; Cynthia Levy; Maria Hernandez; Lennox J. Jeffers; Christopher O’Brien; Paul Martin; Kalyan R. Bhamidimarri

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