viral breakthrough

viral breakthrough

The ability of a virus, such as hepatitis C or HIV, to mutate into a drug-resistant form during treatment with antiviral drugs. The mutation becomes evident when concentrations of the virus reappear in the plasma of treated patients after initially becoming undetectable.
References in periodicals archive ?
[8] Among patients with HBV-induced compensated cirrhosis, HCC occurred in 4.9% of cases with maintained viral response, 11.8% in those with viral breakthrough, and 19.4% of those with a suboptimal response to lamivudine.
Primary outcomes were viral breakthrough or minor virologic breakthrough after the index date.
Three patients in NA-experienced group (Case numbers T0038, 22535, and 18457) and 1 patient in the NA-naive group (Case number L160) developed viral breakthrough. The three cases in the NA-experienced group all had undetectable levels of HBV DNA after 3-6 months of antiviral therapy, but following breakthrough the patients' viral loads were even increased.
(7) Nonetheless, some patients still experience treatment failure due to on-treatment viral breakthrough or relapse after cessation of therapy, possibly attributed to unknown host and viral factors, such as IFNL3 gene polymorphism.
Even within genotype 1, patients with subtype la infections have experienced a higher rate of drug resistance and viral breakthrough than subtype lb.
Overall, there were three treatment failures: one each in groups 3 and 4 had viral breakthrough, and one in group 4 experienced a relapse at week 4.
Overall (87%) patients were having a virological and biochemical response at 12 months of lamivudine treatment and 2 patients were having early viral breakthrough at 6 months after a partial HBV-DNA suppression.
There were no cases of viral breakthrough during therapy, and HCV deep se-quencing in a subgroup of patients detected none of the genetic mutations known to be associated with resistance to sofosbuvir.
with non detectable serum HBV DNA levels, HBsAg and HBeAg seroconversion and viral breakthrough.
No patient was found to be exhibiting viral breakthrough during the treatment.
Nevertheless, despite the availability of approximately 25 antiretroviral drugs from six classes, viral breakthrough, often with the emergence of drug-resistant virus, remains a significant challenge.
The viral breakthrough rate through 12 weeks on setrobuvir plus P/R was low in both treatment-naive patients (2.9%) and patients who had responded inadequately to or relapsed after prior treatment with P/R (3.6%).