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[Lead-in period and week 8 as predictive tools for response to boceprevir therapy: a retrospective study of Spanish
Javier Crespo1, Marina Berenguer2, Francisco Pérez3
1Departamento de Gastroenterología y Hepatología, Hospital Universitario Marqués de Valdecilla, Santander, España.
Introduction:
Most discontinuations due to lack of virological response occur during the first few weeks of hepatitis C virus (HCV) triple therapy. Improved knowledge of baseline factors and their correlation with boceprevir decision points may predict treatment success.
Methods:
An observational, retrospective study was conducted to describe the lead-in period as a clinical decision tool in HCV genotype 1 patients treated with boceprevir. Data were collected from the medical records of 186 consecutive patients distributed across 20 Spanish general hospitals.
Results:
This study included 171 patients. A total of 80% had fibrosis F3/F4, 74% were previously treated, and 26% were treatment-naïve. After the lead-in period, 54.5% of the patients had a reduction of ≥1 log10; this reduction occurred in 52.5% of those with advanced fibrosis. Boceprevir therapy was started in 94% of the patients. Discontinuations at week 4 were limited to null responders with cirrhosis. The baseline factors associated with virological response at week 4 were IL28B, previous response, and fibrosis score. At week 8, HCV-RNA was undetectable in 48.8% of the patients. The correlation between responses at weeks 8 and 12 was 88%.
Conclusion:
In the Spanish clinical setting, lead-in was mainly used as a clinical decision point for non-responders with cirrhosis. The good correlation between stopping rules at weeks 8 and 12 could be used to anticipate discontinuation, thus saving adverse events and costs.
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