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Direct acting antivirals failure: cause and retreatment options
Lucia Parlati1, Stanislas Pol1
1a Department of Hepatology , Cochin Hospital , Paris , France.
Expert Review of Gastroenterology & Hepatology
|February 23, 2019
Summary
Direct-acting antivirals (DAAs) offer a cure for hepatitis C virus (HCV) infection in over 95% of patients. However, treatment failure can occur due to factors like advanced liver disease or specific viral mutations, necessitating further research.
Area of Science:
- Hepatology
- Virology
- Pharmacology
Background:
- Chronic hepatitis C (HCV) is a systemic disease with severe hepatic and extra-hepatic complications.
- Sustained virological response (SVR) significantly reduces mortality and disease manifestations.
- Direct-acting antivirals (DAAs) have revolutionized HCV treatment, offering high cure rates.
Purpose of the Study:
- To review the efficacy and safety of DAAs in treating HCV.
- To evaluate the causes and outcomes of DAA treatment failure.
- To explore challenges in re-treatment strategies for resistant HCV infections.
Main Methods:
- Review of current literature on DAA therapy for HCV.
- Analysis of factors contributing to DAA treatment failure.
- Evaluation of resistance-associated variants (RAVs) and their clinical impact.
Main Results:
- Second-generation DAA regimens achieve SVR in over 95% of patients.
- Treatment failure occurs in 4-5% of cases, often linked to poor adherence, advanced liver disease, or NS5A mutations.
- Optimal treatment duration depends on fibrosis stage, HCV genotype, and viral load.
Conclusions:
- DAAs are highly effective and generally well-tolerated for HCV cure.
- Understanding and addressing DAA failure, including the role of RAVs, is crucial for optimizing re-treatment strategies.
- Further research is needed on the prevalence and clinical relevance of RAVs in retreatment.
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