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Resistance to DAAs: When to Look and When It Matters
1Division of Infectious Diseases, Denver Health Medical Center, 660 Bannock St, MC 4000, Denver, CO, 80204, USA. David.Wyles@dhha.org.
Current HIV/AIDS Reports
|November 9, 2017
Summary
Hepatitis C virus (HCV) resistance-associated substitutions (RASs) are less impactful with new direct-acting antiviral (DAA) therapies. Newer DAA regimens offer improved retreatment options for patients with prior treatment failures.
Area of Science:
- Virology
- Hepatology
- Pharmacology
Background:
- Hepatitis C virus (HCV) resistance-associated substitutions (RASs) can emerge during treatment.
- NS5A inhibitor resistance, in particular, can persist long-term, potentially affecting retreatment outcomes.
Purpose of the Study:
- To review HCV resistance-associated substitutions (RASs) focusing on NS3 protease and NS5A inhibitors.
- To discuss management strategies for HCV resistance, including newer therapies.
Main Methods:
- Literature review of studies on HCV RASs.
- Analysis of treatment outcomes with direct-acting antiviral (DAA) therapies.
Main Results:
- Newer DAA regimens demonstrate improved potency and resistance profiles.
- The clinical impact of HCV RASs is significantly reduced by modern DAA treatments.
- Routine resistance testing may not be essential if newer regimens are available.
Conclusions:
- Newly approved DAA regimens are effective retreatment options for patients with prior treatment failures.
- Factors like cirrhosis and previous treatment history remain crucial for optimizing retreatment.
- The emergence and persistence of HCV RASs have a lessened impact on retreatment success with current therapies.
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