More than 3 million Americans are infected with HCV, and in some countries more than 10 percent of the population is infected. Chronic HCV infection is the leading cause of liver failure worldwide. Response to standard therapy with peginterferon and ribavirin varies widely. Those infected with one strain of the virus—genotype 1—are the least likely to have a successful response to therapy, known as a sustained virological response (SVR). About one-half of patients infected with genotype 1 do not achieve SVR.
Studies have shown that African Americans have consistently lower rates of SVR to interferon-based therapy, compared to Caucasian Americans. A recent study of those with chronic genotype 1 HCV infection found that only 28 percent of African American patients attained SVR, compared with 52 percent in Caucasian Americans. This new study shows that the variation in therapy responsiveness between African Americans and Caucasian Americans can be partly explained by differences in viral response noted as early as one to two days after the first dose of peginterferon.
The study, conducted by a collaborative group of eight medical centers throughout the United States, monitored 341 patients with chronic HCV, genotype 1, who underwent therapy with peginterferon and ribavirin for at least 24 weeks. It focused on response rates to interferon therapy within the first 28 days of therapy, noting viral factors such as HCV RNA levels and host factors such as race, gender, and weight.
Results showed that HCV RNA levels decreased in almost all patients, and that the degree and pattern of decrease, as expected, was different between African and Caucasian Americans. Most important was the new finding that these differences were statistically significant by day 2 of treatment, and that this early viral kinetic measurement was a reliable predictor of ultimate SVR rates. After 28 days of treatment, 22 percent of Caucasian Americans, but only 12 percent of African Americans, were HCV RNA negative.
These findings are particularly important because they point toward the presence of some block or defect in the immediate antiviral response of those who do not respond to therapy. As the authors summarize, "The underlying cause of virological non-response and the reasons why it is more common among African Americans than Caucasian Americans are not clear. [But] the current analyses demonstrated that these differences are fundamentally biologic and become apparent within 24 to 48 hours of starting therapy." As a next step, future research should focus on these host biologic factors that are induced by interferon in an attempt to improve therapy response rates.
In an accompanying editorial, Andrew W. Tai, MD, PhD, and Raymond T. Chung, MD, of Massachusetts General Hospital agree that the findings will prove vital for future research into HCV, remarking, "[this study] demonstrates that the low rates of SVR in African American patients in response to IFN-based therapy appear to result, in large part, from impaired early viral kinetics. Further studies are necessary to uncover the relevant mechanisms that underlie this defect in IFN signaling… with the hope that such mechanisms can be manipulated to restore interferon responsiveness in the otherwise nonresponsive host."
Founded in 1904, The Journal of Infectious Diseases is the premier publication in the Western Hemisphere for original research on the pathogenesis, diagnosis, and treatment of infectious diseases; on the microbes that cause them; and on disorders of host immune mechanisms. Articles in JID include research results from microbiology, immunology, epidemiology, and related disciplines. JID is published under the auspices of the Infectious Diseases Society of America (IDSA). Based in Arlington, Va., IDSA is a professional society representing more than 8,600 physicians and scientists who specialize in infectious diseases.
Steve Baragona | EurekAlert!
Further reports about: > Caucasian descent > HCV > HCV infection > IDSA > Infectious > Infectious Diseases > JID > Peginterferon > RNA > Ribavirin > SVR > chronic genotype 1 HCV infection > chronic hepatitis C > diseases > infectious disease > sustained virological response > viral kinetic measurement > virus—genotype 1
Innovative genetic tests for children with developmental disorders and epilepsy
11.07.2018 | Christian-Albrechts-Universität zu Kiel
Oxygen loss in the coastal Baltic Sea is “unprecedentedly severe”
05.07.2018 | European Geosciences Union
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.
Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...
13.07.2018 | Event News
12.07.2018 | Event News
03.07.2018 | Event News
13.07.2018 | Event News
13.07.2018 | Materials Sciences
13.07.2018 | Life Sciences