Baseline anti-NS4a antibodies in combination with on-treatment quantitative HCV-RNA reliably identifies nonresponders to pegylated interferon-ribavirin combination therapy after 4 weeks of treatment
ABSTRACT Early detection of nonresponders to hepatitis C therapy limits unnecessary exposure to treatment and its side-effects. A recent algorithm combining baseline anti-NS4a antibodies and on-treatment quantitative PCR identified nonresponders to a combination of interferon and ribavirin after 1 week of treatment.
To validate a stopping rule based on baseline anti-NS4a antibody levels and early on-treatment virological response in treatment-naive genotype 1 chronic hepatitis C patients treated with the current standard pegylated interferon and ribavirin combination therapy.
Eighty-nine genotype 1 patients from the Dynamically Individualized Treatment of hepatitis C Infection and Correlates of Viral/Host dynamics Study treated for 48 weeks with standard 180 μg pegylated interferon (PEG-IFN)-α-2a (weekly) and ribavirin 1000-1200 mg (daily) were analysed. Baseline anti-NS4a antibody enzyme-linked immunosorbent assay (NS4a AA 1687-1718) was performed on pretreatment serum. Hepatitis C virus-RNA was assessed at days 0, 1, 4, 7, 8, 15, 22, 29, weeks 6, 7, 8, 10, 12 and 6 weekly thereafter until end of treatment. Multiple regression logistic analysis was performed.
Overall 54 of 89 (61%) patients achieved sustained virological response. A baseline anti-NS4a antibody titre less than 1/1250 correlated with absence of favourable initial viral decline according to variable response types (P = 0.015). The optimal algorithm was developed using the combination of the absence of anti-NS4a Ab (<1/1250) at baseline and the presence of a viral load ≥ 100.000 IU/ml at week 4. This algorithm has a specificity of 43% and negative predictive value of 100% to detect nonresponse to standard PEG-IFN-α-2a and ribavirin therapy at fourth week of therapy (intention-to-treat analysis).
The decision to stop the therapy in genotype 1 chronic hepatitis C patients treated with PEG-IFN-α-2a and ribavirin can be confidently made after 4 weeks of treatment based on the absence of baseline anti-NS4a Ab and a week-4 hepatitis C virus-RNA above 100.000 IU/ml.
Full-textDOI: · Available from: Geert Leroux-Roels, Jan 05, 2015
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ABSTRACT: Many patients with chronic hepatitis C virus (HCV) being treated with pegylated interferon (peg-IFN) plus ribavirin (RBV) do not respond to therapy and do not clear the virus. Standard of care during the era of dual therapy was to discontinue the patient's therapy based on insufficient decreases in viral load after 12 and/or 24 weeks on therapy. We identified patient characteristics that were significant predictors of discontinuation as a result of lack of efficacy (LOE) in a national database of US veterans with genotypes 1 and 4. We identified US veterans who received care at Veterans Affairs medical centers in 2004-2009 and who had lab-confirmed HCV diagnoses and initiated therapy with peg-IFN plus RBV. Patients who discontinued therapy early were classified as either LOE or non-LOE discontinuers based on pharmacy refill patterns and laboratory response data. Predictors of LOE discontinuation were identified using univariate and multivariable Cox proportional hazards modeling. Of 321 238 HCV patients with an ICD-9 diagnosis code, 31 215 (9.7%) initiated dual therapy with peg-IFN plus RBV, and 10 333 (3.2%) met all inclusion criteria and were included in the analysis. Overall, 13.6% of the cohort was classified as LOE. Significant predictors of LOE discontinuation included treatment for drug abuse (hazard ratio [HR] = 2.18), age >65 years (HR = 1.75), antiretroviral therapy for HIV (HR = 1.48), black race (HR = 1.47), platelet count >100/mm(3) (HR = 1.46), and drug therapy for insomnia (HR = 1.40). We identified risk factors for discontinuation caused by LOE. Future work should focus on determining whether these characteristics are also predictive of triple-therapy LOE discontinuations.Annals of Pharmacotherapy 04/2014; 48(7). DOI:10.1177/1060028014531724 · 2.92 Impact Factor