The Real World Analysis of Drug-Drug Interactions of Grazoprevir/Elbasvir in Treatment of Chronic Hepatitis C Patients in Taiwan
Conditions: Drug Interaction Potentiation
Sponsor: National Cheng-Kung University Hospital

Title: The Real World Analysis of Drug-Drug Interaction of Grazoprevir/Elbasvir in 
Treatment of Chronic Hepatitis C patients in Taiwan 
 
Protocol No: MISP#57751 
 
Date: 28 July 2018 
 
 
 

Study Protocol 
 
This is a multi-center, retrospective study. 
Numbers of site & Subjects: 5 hospitals in Taiwan and 400 patients 
 
Patient enrolled criteria: Patients treated with grazoprevir/elbasvir during August 2017 
to July 2018 are candidates of study subjects.  
All the required study information will be recorded with detailed chart review.  
 
Items of record: Patient’s Demographics, HCV viral load, HCV Genotype, Fibrosis status, 
HCC status, Child-Pugh score for cirrhosis, CHC treatment History, HBV co-infection, HIV 
co-infection, solid organ transplantation status, co-morbid diseases, medication used 
before and through the 12 weeks or 16 weeks of grazoprevir/elbasvir including class and 
number. 
 
Evaluation tool: HEP Drug Interactions (www.hep-druginteractions.org) 
 
Assessment of co-medications:  
Category 0: Classification not possible due to lack of information  
Category 1: No clinical interaction possible  
Category 2: May require dose adjustment/closer monitoring  
Category 3: Co-administration not recommended or contraindicated 
 
Detailed co-medications before and through 12 weeks or 16 weeks of 
grazoprevir/elbasvir treatment will be reviewed and recorded. The assessment of DDIs 
will be evaluated by HEP Drug Interactions (www.hep-druginteractions.org) and 
recorded according to the suggested categories. Co-morbid diseases will be recorded 
before grazoprevir/elbasvir treatment according organ systems. 
 
To assess the number of patients at risk for a clinically relevant DDI, the ratio of 
patients with at least one predicted DDI between co-medication and 
grazoprevir/elbasvir will be calculated. 
 
Statistical Analysis 
Data will be expressed as percentages. To assess the number of patients at risk for a 
clinically relevant DDI, the ratio of patients with at least one predicted DDI between 
co-medication and grazoprevir/elbasvir will be calculated. The difference will be 
compared by Chi-square or Fisher exact test. Two-tailed P values less than 0.05 is 

considered to be significant. SPSS version 17 will be used for statistical analysis.