Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Stephen D. Shafran is active.

Publication


Featured researches published by Stephen D. Shafran.


The New England Journal of Medicine | 2015

Sofosbuvir and Velpatasvir for HCV Genotype 1, 2, 4, 5, and 6 Infection

Jordan J. Feld; Ira M. Jacobson; Christophe Hézode; Tarik Asselah; Peter J. Ruane; Norbert Gruener; Armand Abergel; Alessandra Mangia; Ching-Lung Lai; Henry L.Y. Chan; Francesco Mazzotta; Christophe Moreno; Eric Yoshida; Stephen D. Shafran; William J. Towner; Tram T. Tran; John McNally; Anu Osinusi; Evguenia Svarovskaia; Yanni Zhu; Diana M. Brainard; John G. McHutchison; Kosh Agarwal; Stefan Zeuzem

BACKGROUND A simple treatment regimen that is effective in a broad range of patients who are chronically infected with the hepatitis C virus (HCV) remains an unmet medical need. METHODS We conducted a phase 3, double-blind, placebo-controlled study involving untreated and previously treated patients with chronic HCV genotype 1, 2, 4, 5, or 6 infection, including those with compensated cirrhosis. Patients with HCV genotype 1, 2, 4, or 6 were randomly assigned in a 5:1 ratio to receive the nucleotide polymerase inhibitor sofosbuvir and the NS5A inhibitor velpatasvir in a once-daily, fixed-dose combination tablet or matching placebo for 12 weeks. Because of the low prevalence of genotype 5 in the study regions, patients with genotype 5 did not undergo randomization but were assigned to the sofosbuvir-velpatasvir group. The primary end point was a sustained virologic response at 12 weeks after the end of therapy. RESULTS Of the 624 patients who received treatment with sofosbuvir-velpatasvir, 34% had HCV genotype 1a, 19% genotype 1b, 17% genotype 2, 19% genotype 4, 6% genotype 5, and 7% genotype 6. A total of 8% of patients were black, 19% had cirrhosis, and 32% had been previously treated for HCV. The rate of sustained virologic response among patients receiving sofosbuvir-velpatasvir was 99% (95% confidence interval, 98 to >99). Two patients receiving sofosbuvir-velpatasvir, both with HCV genotype 1, had a virologic relapse. None of the 116 patients receiving placebo had a sustained virologic response. Serious adverse events were reported in 15 patients (2%) in the sofosbuvir-velpatasvir group and none in the placebo group. CONCLUSIONS Once-daily sofosbuvir-velpatasvir for 12 weeks provided high rates of sustained virologic response among both previously treated and untreated patients infected with HCV genotype 1, 2, 4, 5, or 6, including those with compensated cirrhosis. (Funded by Gilead Sciences; ClinicalTrials.gov number, NCT02201940.).


The New England Journal of Medicine | 1996

A Comparison of Two Regimens for the Treatment of Mycobacterium avium Complex Bacteremia in AIDS: Rifabutin, Ethambutol, and Clarithromycin versus Rifampin, Ethambutol, Clofazimine, and Ciprofloxacin

Stephen D. Shafran; Joel Singer; Donald P. Zarowny; Peter Phillips; Irving E. Salit; Sharon Walmsley; Ignatius W. Fong; M. John Gill; Anita Rachlis; Richard Lalonde; Mary M. Fanning; Christos M. Tsoukas

BACKGROUND Bacteremia with the Mycobacterium avium complex is common in patients with the acquired immunodeficiency syndrome (AIDS), but the most effective treatment for this infection remains unclear. METHODS We randomly assigned 229 patients with AIDS and M. avium complex bacteremia to receive either rifampin (600 mg daily), ethambutol (approximately 15 mg per kilogram of body weight daily), clofazimine (100 mg daily), and ciprofloxacin (750 mg twice daily) (the four-drug group) or rifabutin (600 mg daily), ethambutol (as above), and clarithromycin (1000 mg twice daily) (the three-drug group). In the three-drug group the dose of rifabutin was reduced by half after 125 patients were randomized, because 24 of 63 patients had uveitis. RESULTS Among 187 patients who could be evaluated, blood cultures became negative more often in the three-drug group than in the four-drug group (69 percent vs. 29 percent, P<0.001). Among patients treated for at least four weeks, the bacteremia resolved more frequently in the three-drug group (78 percent vs. 40 percent, P<0.001). In the three-drug group, bacteremia resolved more often with the 600-mg dose of rifabutin than with the 300-mg dose (P=0.025), but the latter regimen was more effective than the four-drug regimen (P<0.05). The median survival was 8.6 months in the three-drug group and 5.2 months in the four-drug group (P = 0.001). The median Karnofsky performance score was higher in the three-drug group than in the four-drug group from week 2 to week 16 (P<0.05). Mild uveitis developed in 3 of the 53 patients receiving the 300-mg dose of rifabutin, an incidence about one quarter that observed with the 600-mg dose (P<0.001). CONCLUSIONS In patients with AIDS and M. avium complex bacteremia, treatment with the three-drug regimen of rifabutin, ethambutol, and clarithromycin leads to resolution of the bacteremia more frequently and more rapidly than treatment with rifampin, ethambutol, clofazimine, and ciprofloxacin, and survival rates are better.


Hiv Medicine | 2005

The effect of low‐dose ritonavir monotherapy on fasting serum lipid concentrations

Stephen D. Shafran; Ld Mashinter; Se Roberts

Ritonavir (RTV) at doses of 400 mg twice a day (bid) or higher adversely affects serum lipids. However, the effect of RTV 100 mg bid on serum lipids is unknown. We conducted a study to evaluate the effect of RTV 100 mg bid on fasting serum lipid profiles in HIV‐negative healthy volunteers.


Canadian Journal of Gastroenterology & Hepatology | 2007

Management of chronic hepatitis C: Consensus guidelines

Morris Sherman; Stephen D. Shafran; Kelly W. Burak; Karen Doucette; Winnie Wong; Nigel Girgrah; Eric M. Yoshida; Eberhard L. Renner; Philip Wong; Marc Deschenes

Since the last consensus conference on the management of chronic viral hepatitis, a number of studies looking at modifications of the standard course of treatment have been published. These changes have been sufficiently substantive to warrant review to determine whether any changes in the recommended treatment algorithms are needed. A consensus development conference was held in January 2007, and the present document highlights the results of the presentations and discussion about these issues. It reviews the epidemiology of hepatitis C in Canada, treatment of acute hepatitis C and new algorithms in chronic hepatitis C, including retreatment of previous treatment failures. In addition, sections on management of hepatitis C in special populations have been updated. There is also a section on the use of hematopoietic growth factors to help manage patients on therapy. The document should be read in conjunction with the previous document to identify changes. Some recommendations made in the previous document remain and are not discussed here.


Gut | 2015

Daclatasvir plus peginterferon alfa and ribavirin for treatment-naive chronic hepatitis C genotype 1 or 4 infection: a randomised study

Christophe Hézode; Gideon M. Hirschfield; Wayne Ghesquiere; William Sievert; Maribel Rodriguez-Torres; Stephen D. Shafran; Paul J. Thuluvath; Harvey A Tatum; Imam Waked; Gamal Esmat; Eric Lawitz; Vinod K. Rustgi; Stanislas Pol; Nina Weis; Paul J. Pockros; Marc Bourlière; Lawrence Serfaty; John M. Vierling; Michael W. Fried; Ola Weiland; Maurizia Rossana Brunetto; Gregory T. Everson; Stefan Zeuzem; Paul Y. Kwo; Mark S. Sulkowski; Norbert Bräu; Dennis Hernandez; Fiona McPhee; Megan Wind-Rotolo; Zhaohui Liu

Objective To evaluate the safety and efficacy of daclatasvir, an HCV NS5A inhibitor with pangenotypic activity, administered with peginterferon-alfa-2a/ribavirin. Design In this Phase 2b double-blind, placebo-controlled study, treatment-naive adults with HCV genotype 1 (N=365) or 4 (N=30) infection were randomly assigned (2:2:1) to daclatasvir 20 mg or 60 mg, or placebo once daily plus weekly peginterferon-alfa-2a and twice-daily ribavirin. Daclatasvir recipients achieving protocol-defined response (PDR; HCV-RNA<lower limit of quantitation at Week 4 and undetectable at Week 10) were rerandomised at Week 12 to continue daclatasvir/peginterferon-alfa-2a/ribavirin for 24 weeks total duration or to placebo/peginterferon-alfa-2a/ribavirin for another 12 weeks. Patients without PDR and placebo patients continued peginterferon-alfa/ribavirin through Week 48. Primary efficacy endpoints were undetectable HCV-RNA at Weeks 4 and 12 (extended rapid virologic response, eRVR) and at 24 weeks post-treatment (sustained virologic response, SVR24) among genotype 1-infected patients. Results Overall, eRVR was achieved by 54.4% (80/147) of genotype 1-infected patients receiving daclatasvir 20 mg, 54.1% (79/146) receiving 60 mg versus 13.9% (10/72) receiving placebo. SVR24 was achieved among 87 (59.2%), 87 (59.6%), and 27 (37.5%) patients in these groups, respectively. Higher proportions of genotype 4-infected patients receiving daclatasvir 20 mg (66.7%; 8/12) or 60 mg (100.0%; 12/12) achieved SVR24 versus placebo (50.0%; 3/6). A majority of daclatasvir-treated patients achieved PDR and experienced less virologic failure and higher SVR24 rates with a shortened 24-week treatment duration. Adverse events occurred with similar frequency across all treatment groups. Conclusions The combination of daclatasvir/peginterferon-alfa/ribavirin was generally well tolerated and achieved higher SVR24 rates compared with placebo/peginterferon-alfa/ribavirin among patients infected with HCV genotype 1 or 4. Trial registration number NCT01125189.


Clinical Infectious Diseases | 1999

A Randomized, Placebo-Controlled Study of Rifabutin Added to a Regimen of Clarithromycin and Ethambutol for Treatment of Disseminated Infection with Mycobacterium avium Complex

Fred M. Gordin; Paul M. Sullam; Stephen D. Shafran; David L. Cohn; Beverley A. Wynne; Linda Paxton; Kim Perry; Charles R. Horsburgh

Current guidelines suggest that disseminated Mycobacterium avium complex (MAC) infection be treated with a macrolide plus ethambutol or rifabutin or both. From 1993 to 1996, 198 AIDS patients with MAC bacteremia participated in a prospective, placebo-controlled trial of clarithromycin (500 mg b.i.d.) plus ethambutol (1,200 mg/d), with or without rifabutin (300 mg/d). At 16 weeks, 63% of patients in the rifabutin group and 61% in the placebo group (P = .81) had responded bacteriologically. Changes in clinical symptoms and time to survival were similar in both groups. Development of clarithromycin resistance during therapy was similar in the two groups; of patients who had a bacteriologic response, however, only 1 of 44 (2%) receiving rifabutin developed clarithromycin resistance, vs. 6 of 42 (14%) in the placebo group (P = .055). Thus, rifabutin had no impact on bacteriologic response or survival but may protect against development of clarithromycin resistance in those who respond to therapy.


Canadian Journal of Gastroenterology & Hepatology | 2007

Management of chronic hepatitis B: Consensus guidelines

Morris Sherman; Stephen D. Shafran; Kelly W. Burak; Karen Doucette; Winnie Wong; Nigel Girgrah; Eric M. Yoshida; Eberhard L. Renner; Philip Wong; Marc Deschenes

The present document presents the proceedings of the consensus development conference on the management of viral hepatitis held in January 2007 under the auspices of the Canadian Association for the Study of the Liver and the Association of Medical Microbiology and Infectious Disease Canada. Several new agents have become available since the last such document was published in 2004, and new information has become available to help assess risk of adverse outcomes and who should be treated. In addition, the participants at the meeting identified a number of structural barriers that exist uniquely in Canada and that prevent physicians from properly managing their patients. The conference discussed the selection of patients for treatment and the drugs that can be used to treat these patients, as well as the treatment of hepatitis B in special populations. The present document should be read in conjunction with the companion document on the management of chronic hepatitis C.


Journal of Clinical Virology | 2004

Once, twice, or three times daily famciclovir compared with aciclovir for the oral treatment of herpes zoster in immunocompetent adults: a randomized, multicenter, double-blind clinical trial

Stephen D. Shafran; Stephen K. Tyring; Richard Ashton; Jacque Decroix; Chistine Forszpaniak; Alan Wade; Christian Paulet; Daniel Candaele

BACKGROUND Famciclovir, the well absorbed oral pro-drug of penciclovir, is effective in the treatment of herpes zoster when given three times daily. Because the intracellular half-life of penciclovir triphosphate in varicella-zoster virus (VZV)-infected cells (7h) is considerably longer than that of aciclovir triphosphate (1h), it may be possible to administer famciclovir less frequently than three times daily for herpes zoster: aciclovir is administered five times daily. METHODS 559 immunocompetent adults presenting with herpes zoster whose skin lesions were present for less than 72 h were randomized to receive famciclovir 750 mg once daily (od), 500 mg twice daily (bid), or 250 mg three times daily (tid), or aciclovir 800 mg five times daily. All treatments were given for 7 days. Participants were evaluated until complete healing or for 4 weeks, whichever occurred first. RESULTS There were no significant differences between the four treatment groups with respect to times to full crusting; loss of vesicles, ulcers and crusts; cessation of new lesion formation; a 50% reduction in the area of affected skin; and the loss of acute pain. CONCLUSIONS Famciclovir 750 mg once daily, 500 mg twice daily and 250 mg daily, and aciclovir 800 mg five times daily are three times comparable in efficacy with respect to the cutaneous healing of herpes zoster. The current study was not designed to assess the effects of the treatments on postherpetic neuralgia (PHN).


Gastroenterology | 2017

Efficacy of 8 Weeks of Sofosbuvir, Velpatasvir, and Voxilaprevir in Patients With Chronic HCV Infection: 2 Phase 3 Randomized Trials

Ira M. Jacobson; Eric Lawitz; Edward Gane; Bernard Willems; Peter Ruane; Ronald Nahass; Sergio M. Borgia; Stephen D. Shafran; Kimberly A. Workowski; Brian Pearlman; Robert H. Hyland; Luisa M. Stamm; Evguenia Svarovskaia; Hadas Dvory-Sobol; Yanni Zhu; G. Mani Subramanian; Diana M. Brainard; John G. McHutchison; Norbert Bräu; Thomas Berg; Kosh Agarwal; Bal Raj Bhandari; Mitchell Davis; Jordan J. Feld; Gregory J. Dore; Catherine A. Stedman; Alexander J. Thompson; Tarik Asselah; Stuart K. Roberts; Graham R. Foster

BACKGROUND & AIMS Patients with chronic hepatitis C virus (HCV) infection have high rates of sustained virologic response (SVR) after 12 weeks of treatment with the nucleotide polymerase inhibitor sofosbuvir combined with the NS5A inhibitor velpatasvir. We assessed the efficacy of 8 weeks of treatment with sofosbuvir and velpatasvir plus the pangenotypic NS3/4A protease inhibitor voxilaprevir (sofosbuvir-velpatasvir-voxilaprevir). METHODS In 2 phase 3, open-label trials, patients with HCV infection who had not been treated previously with a direct-acting antiviral agent were assigned randomly to groups given sofosbuvir-velpatasvir-voxilaprevir for 8 weeks or sofosbuvir-velpatasvir for 12 weeks. POLARIS-2, which enrolled patients infected with all HCV genotypes with or without cirrhosis, except patients with genotype 3 and cirrhosis, was designed to test the noninferiority of 8 weeks of sofosbuvir-velpatasvir-voxilaprevir to 12 weeks of sofosbuvir-velpatasvir using a noninferiority margin of 5%. POLARIS-3, which enrolled patients infected with HCV genotype 3 who had cirrhosis, compared rates of SVR in both groups with a performance goal of 83%. RESULTS In POLARIS-2, 95% (95% confidence interval [CI], 93%-97%) of patients had an SVR to 8 weeks of sofosbuvir-velpatasvir-voxilaprevir; this did not meet the criterion to establish noninferiority to 12 weeks of sofosbuvir-velpatasvir, which produced an SVR in 98% of patients (95% CI, 96%-99%; difference in the stratum-adjusted Mantel-Haenszel proportions of -3.2%; 95% CI, -6.0% to -0.4%). The difference in the efficacy was owing primarily to a lower rate of SVR (92%) among patients with HCV genotype 1a infection receiving 8 weeks of sofosbuvir-velpatasvir-voxilaprevir. In POLARIS-3, 96% of patients (95% CI, 91%-99%) achieved an SVR in both treatment groups, which was significantly superior to the performance goal. Overall, the most common adverse events were headache, fatigue, diarrhea, and nausea; diarrhea and nausea were reported more frequently by patients receiving voxilaprevir. In both trials, the proportion of patients who discontinued treatment because of adverse events was low (range, 0%-1%). CONCLUSIONS In phase 3 trials of patients with HCV infection, we did not establish that sofosbuvir-velpatasvir-voxilaprevir for 8 weeks was noninferior to sofosbuvir-velpatasvir for 12 weeks, but the 2 regimens had similar rates of SVR in patients with HCV genotype 3 and cirrhosis. Mild gastrointestinal adverse events were associated with treatment regimens that included voxilaprevir. ClinicalTrials.gov numbers: POLARIS-2, NCT02607800; and POLARIS-3, NCT02639338.


Journal of Hepatology | 2015

O059 : Long-term persistence of HCV NS5A variants after treatment with NS5A inhibitor ledipasvir

Hadas Dvory-Sobol; David L. Wyles; W. Ouyang; K. Chodavarapu; John McNally; Wendy Cheng; Stephen D. Shafran; Alessandra Mangia; C. Schwabe; M.D. Miller; Hongmei Mo

O059

Collaboration


Dive into the Stephen D. Shafran's collaboration.

Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Sharon Walmsley

University Health Network

View shared research outputs
Top Co-Authors

Avatar

Edward Gane

Auckland City Hospital

View shared research outputs
Top Co-Authors

Avatar

Stefan Zeuzem

Goethe University Frankfurt

View shared research outputs
Top Co-Authors

Avatar

Brian Conway

University of British Columbia

View shared research outputs
Top Co-Authors

Avatar

Peter Phillips

University of British Columbia

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Joel Singer

University of British Columbia

View shared research outputs
Researchain Logo
Decentralizing Knowledge