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Published on: September 12, 2016
Triple Therapy with First Generation Protease Inhibitors for Hepatitis C Markedly Impairs Function of Neutrophil
Walter Spindelboeck1, Angela Horvath1, Monika Tawdrous1
1Department of Internal Medicine, Division of Gastroenterology and Hepatology, Medical University of Graz, Graz, Austria.
Insights
First-generation HCV protease inhibitors increase infection rates in chronic hepatitis C patients by impairing neutrophil function. This immune suppression may impact treatment success and survival, highlighting a critical safety concern.
Area of Science:
- Immunology
- Hepatology
- Pharmacology
Background:
- First-generation HCV protease inhibitors improved viral clearance for chronic hepatitis C (CHC).
- However, these treatments correlated with increased infection rates and mortality, particularly in advanced liver disease.
- The impact of these inhibitors on immune function remained unclear.
Purpose of the Study:
- To investigate whether first-generation HCV protease inhibitors affect neutrophil function.
- To correlate neutrophil function with infection rates during CHC treatment.
Main Methods:
- Retrospective and prospective study of CHC patients treated with peginterferon and ribavirin, with or without protease inhibitors.
- Evaluation of infection data in 108 retrospective and 44 prospective CHC patients.
- Assessment of neutrophil phagocytosis, oxidative burst, elastase, and diamine oxidase levels in prospective patients (n=44).
Main Results:
- Patients on protease inhibitor therapy experienced significantly higher rates of clinically relevant infections (31% and 26%) compared to those on dual therapy (13% and 0%).
- Neutrophil phagocytosis decreased by 40% with protease inhibitor addition but recovered post-treatment.
- Protease inhibitors appeared to reduce serum elastase but did not affect gut permeability.
Conclusions:
- Impaired neutrophil function during first-generation HCV protease inhibitor therapy may explain increased infection rates.
- This immune modulation could influence treatment outcomes and patient survival in chronic hepatitis C.
- Further research is needed to optimize antiviral strategies considering immune effects.
Abstract:
First-generation HCV protease inhibitors represent a milestone in antiviral therapy for chronic hepatitis C infection (CHC), but substantially increased rates of viral clearance are offset by increased rates of infection and infection-associated deaths, especially of patients with advanced liver disease. We aimed to assess whether first generation protease inhibitors interfere with neutrophil function. We included 108 consecutive, retrospective CHC patients and 44 consecutive, prospective CHC patients who were treated with peginterferon and ribavirin with or without protease inhibitors according to the guidelines in the period of November 2012 to June 2015. 33 healthy volunteers served as controls. Infection data were evaluated in all patients. Neutrophil phagocytosis, oxidative burst, elastase and diamine oxidase levels during 12 weeks of triple (n = 23) or dual therapy (n = 21) were studied in the prospective part. In the retro- and prospective cohorts patients experiencing clinically relevant infections were significantly more frequent during protease inhibitor therapy (31% and 26%) than during therapy with peginterferon and ribavirin (13% and 0%). Neutrophil phagocytosis decreased to 40% of baseline with addition of protease inhibitors to P/R but recovered 6 months after end of treatment. Protease inhibitors also seemed to reduce serum elastase levels but did not impact on gut permeability. Impaired neutrophil function during triple therapy with first generation HCV protease inhibitors may explain the high infection rate associated to these treatments and be of relevance for treatment success and patient survival.
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