Ezetimibe as a Safe and Efficacious Treatment for Chronic Hepatitis C
Phase: PHASE2
Conditions: Chronic Hepatitis C
Sponsor: VA Office of Research and Development

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Protocol Title: Ezetimibe as a Safe and Efficacious Treatment for Chronic Hepatitis C 
 
NCT number:   02971033 
 
 
Protocol Date:   3/30/22 
 

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I. 
ABSTRACT 
While Hepatitis C virus (HCV) infects ~2% of people in the United States (US), 1 in 10 Veterans are 
chronically infected. Hence, US Veterans are infected at a rate 5 times greater than the general population 
accounting for almost half of the HCV patients in the country. This is of major concern for the veteran 
population because not only does chronic HCV infection lead to liver steatosis, insulin resistance, chronic 
inflammation, and fibrosis, but increases in HCV cirrhosis have played a major role in the rise in 
hepatocellular carcinoma, accounting for the majority (~50-60%) of cases in the US. Hence, there is a 
practical need for more affordable effective HCV antivirals with high barriers to viral resistance and/or ways 
to shorten the current expensive treatment duration.  
 
Viral entry into permissive cells is a recognized antiviral target. In addition, blocking cell-to-cell spread has 
been shown to enhance antiviral drug efficacy, limit viral escape that may arise against other antivirals within 
combination drug cocktails and enhance drug synergy. We and others have shown that HCV entry inhibitors 
can act synergistically with current HCV DAAs allowing for more rapid viral clearance. This combined with 
our recent proof-of-concept study showing the utility of mathematical modeling of early on treatment viral 
response to interferon-free HCV DAA therapy as a means to optimize the duration of treatment, provides 
confidence that improvements can be made. 
 
As such, our long term goal is to develop affordable therapeutic and prophylactic regimens to prevent HCV 
entry/spread and test the efficacy of those inhibitors in patients. Toward this end, our laboratory has shown 
that the Niemann-Pick C1 Like-1 (NPC1L1) cellular cholesterol uptake receptor is required for HCV entry into 
hepatocytes. Furthermore, we have shown that ezetimibe (EZE) (Ezetrol®, Ezetimibe®, and Zetia®), a drug 
that inhibits NPC1L1-mediated cholesterol uptake and is FDA-approved as lipid lowering agent for treatment 
of hypercholesterolemia, blocks HCV entry in hepatoma cells in vitro and human hepatocytes transplanted 
into uPA-SCID mice. Furthermore, retrospective analysis of the National VA database using multivariable 
logistic regression models to control for age, sex, race, alcohol use, drug use, and other co-morbidities, we 
found HCV prevalence to be lower (p <.001) and early interferon/ribavirin treatment response kinetics to be 
better in patients taking EZE. Together all this suggests that EZE might lead to cure within a shorter DAA-
based treatment window, increase the barrier to viral escape, and perhaps ultimately be useful as a 
prophylactic to prevent re-infection.  
 
The objective of this study is to assess the efficacy of EZE as adjunct to DAAs for the treatment of chronic 
HCV. We hypothesize that when included in combination treatment regimens that EZE will augment 2nd 
phase HCV decline resulting in faster viral clearance (i.e. shorter/cheaper DAA therapy).  
 
 
 
 
AIM. Assess the efficacy of EZE as an adjunct therapy in chronically HCV infected patients 
undergoing HCV DAA treatment.  
 
 
Relevance to VA. (1) Veterans are not only the ideal study population, but also a population that would derive 
immediate benefit if the proposed study confirms that EZE shortens DAA treatment. (2) To provide a proof-
of-concept regarding the importance of blocking viral cell-to-cell spread as part of an optimal antiviral strategy 
advancing knowledge about drug synergy and how to increase the barrier to viral escape, a critical concern 
for all emerging RNA viruses that might affect our troops.  
 
II. BACKGROUND AND SIGNIFICANCE 
 
 
HCV treatment. Recently we have seen the release of IFN-free, all oral HCV DAA treatment regimens with 
cure rates near 100%.  While this is an amazing breakthrough in HCV treatment, caveats remain. First, 
although high sustained virological response (SVR) rates have been achieved, viral escape has been 
documented raising questions regarding the extent of viral resistance that might be encountered in real-life 
populations. The second issue is that the high cost of these drugs have left many around the world being 
denied treatment.  Hence, there is a need to prevent viral escape and reduce treatment cost. Here we 
propose to investigate the re-indication of a readily available FDA-approved drug for the benefit to those 
chronically infected with HCV. 
 
Clinical significance of viral entry/spread inhibitors. Viral entry represents a promising opportunity for drug 
discovery; however, no HCV entry inhibitors have been FDA-approved. In addition, evidence is accumulating 
that blocking not only cell-free virus entry, but also viral cell-to-cell spread is an important untapped area for 
antiviral intervention. Relevant to all RNA viruses, blocking spread has been documented experimentally to 

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prevent viral escape that may arise against other antivirals within a combination drug cocktail[1,2]. Even more 
broadly applicable (i.e. to any pathogen), we[3,4] and others[5] have shown that entry/spread inhibitors act 
synergistically with IFN and DAAs resulting in more effective and rapid viral clearance. Additionally, others 
suggest that because viral cell-to-cell confers higher per cell virus doses, that blocking this transmission can 
actually reduce the effective dose of drug required thus enhancing antiviral drug efficacy[6].  
 
EZE inhibits HCV infection in vitro and in vivo. We have identified NPC1L1 as a factor required for cell-free 
HCV entry[7], and shown it is also required for HCV cell-to-cell transmission[3],. Consistent with this ezetimibe 
(EZE), an NPC1L1 internalization inhibitor [8-13], 
reduced HCV foci formation in a dose-dependent 
manner when present 6h prior to infection and then 
removed (Pre) or when present during the 12h virus 
inoculation period and then removed (Co); however 
consistent with an entry inhibitor, inhibition was 
inefficient when EZE was added post-infection (Post) 
(Fig. 1d).  Likewise, EZE was able to inhibit HCV 
infection in a hepatic xenorepopulation murine 
model[14.15]. Specifically, uPA-SCID mice repopulated 
with human hepatocytes[16,17] were pre-treated with 
EZE (10 mg/kg/day; a dose that produces serum 
levels achieved in patients) or diluent for 2 wks prior 
to infection with HCV GT1b serum. While 100% of the diluent-treated mice were HCV+ by RT-qPCR 1 wk 
following inoculation, 71% (5/7) of EZE-treated mice were HCV-negative (Fig.1e) 
despite the fact that drug treatment stopped at the time of infection.  
 
 
EZE act synergistically with HCV DAAs[4]. Importantly, EZE enhances treatment 
efficacy when used in combination with antivirals that block intracellular virus 
amplification (Fig. 2) Specifically, we have found that EZE synergizes with 
protease inhibitors (Fig.2a), polymerase inhibitors (Fig.2b), and NS5a inhibitors. 
 
EZE impacts HCV outcomes. To confirm the clinical relevance of EZE, we 
performed retrospective analysis of the National 
Health 
and 
Nutrition 
Examination 
Survey 
(NHANES) and the National VA databases. In 
NHANES, we observed a significantly (p=.02) 
lower rate of HCV seroprevalence in people on 
EZE (0.2%) versus those not on EZE (1.7%). In the 
larger VA database where multivariable logistic 
regression models could be used to control for 
age, sex, race, alcohol use, drug use, and other 
co-morbidities, we again found HCV prevalence to 
be lower (p <.001) in patients on EZE supporting that EZE blocks HCV 
infection in people. Furthermore, analysis of treatment response revealed that 
despite the older age, larger percentage of African Americans, higher viral 
load and more severe liver disease (e.g. higher ALT/AST) of the population 
taking EZE, IFN/RBV treatment response was better (i.e. larger viral log reduction) in patients taking EZE. 
One caveat of this retrospective analysis, however, is that in the VA system EZE is almost exclusively 
prescribed as an add-on to statin treatment. Hence, while it was clear that statins alone had no effect on 
HCV treatment response (Fig. 3a dark blue line), the significantly better response kinetics seen in those 
taking EZE (Fig. 3a, red line) occurred in patients taking a combination of EZE and a statin.  
 
III. RESEARCH DESIGN AND METHODS 
This is a prospective study in which we propose to compare HCV RNA inhibition in patient undergoing 
available HCV DAA treatment plus EZE or a placebo.  
 
 
Subjects: Subjects will consist of patients at the Hines VA, who are scheduled to receive HCV DAA therapy 
and who meet the following specific inclusion and exclusion criteria: 
Fig. 1 EZE inhibits HCV infection. (d) Huh7 cells were treated 
with increasing doses of EZE infected with HCVcc and HCV RNA 
levels determined 72h p.i. by RTqPCR. (e) HCV RNA Copies/ml of 
serum in mock- and ezetimibe-treated chimeric mice was quantified 
by RTqPCR 1 week post inoculation with HCV+ genotype 1b serum. 
[* = (p<0.05)]. 
Fig. 2 Infected cells were treated 
as indicated. RNA was isolated 
from triplicates at indicated times 
and HCV copies were determined 
by RT-qPCR. (a) EZE enhances 
inhibition by the HCV protease 
inhibitor 
ITMN5537; 
(b) 
EZE 
enhances inhibition by the HCV 
polymerase inhibitor RG7128. 
20
40
60
80
10
Hours Treatment
Mock
PI (ITMN5537)
EZE
PI + EZE
106
0
HCV copies/ug RNA
105
104
103
102
 
 
Fig. 3 EZE (Zetia©) enhances 
HCV treatment in patients. In the 
VA EZE is prescribed with a statin. 
Hence we used those taking a statin 
only as a control group. Shown is the 
average log HCV drop from baseline 
in each group.  (HL = hyperlipidemia)

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Inclusion Criteria 
Exclusion Criteria 
1. Intent to treat with MAVYRET 
2. Males/females 18 - 70 yrs of age. 
3. Serum HCV RNA >2,000 IU/ml. 
4. Other causes of chronic liver disease 
excluded by appropriate clinical, laboratory, 
or histologic evaluation  
5. The following hematological criteria must be 
met:  
 
Hemoglobin > 12 g/dl. 
 
Absolute neutrophil count (ANC) > 
1.0x109 /L 
 
Platelets  150 x 108 /L (i.e normal) 
6. Serum creatinine <1.5 times the upper limit 
of normal (ULN) at screening.  
7. Fasting blood sugar normal for non-diabetics 
or hemoglobin A1C < 8.5% with diabetes.  
8. Women of childbearing potential must have 
a negative pregnancy test prior to receiving 
treatment.  Sexually active women must take 
adequate precautions to prevent pregnancy 
during the study.  Pregnancy tests will be 
done at the final clinic visits and every 4 wks. 
9. Patient provides written informed consent. 
1. Evidence of liver disease other than HCV:  
 
ANA >1:160 
 
Active alcoholic liver disease.   
 
Hepatitis B surface antigen positive. 
 
Hemochromatosis.  
 
Wilson disease. 
 
Alpha-1-antitrypsin deficiency.  
 
Recent hepatotoxic drug exposure. 
 
Cirrhosis with complications of portal hypertension 
including esophageal varices (> grade 1 by endoscopy), 
ascites, or hepatic encephalopathy, or bilirubin >2.0 
mg/dl and/or overall Child-Pugh Score > 7. 
2. Use of oral cyclosporine, fibric acid, Fenofibrate, 
gemfibrozil or cholestyramine 
3. Active substance abuse including, but not limited to alcohol 
or i.v./inhaled drugs  
4. Use of chemotherapy or systemic steroid therapy within 30 
days prior to enrollment. 
5. Pregnancy, females who are breast feeding, or females of 
child bearing potential who are not using adequate birth 
control measures. 
6. History of a medical condition that could interfere with 
participation or completion of the protocol. 
7. Organ transplant recipient.  
8. History of hypersensitivity to ezetimibe. 
[Note: Based on currently available therapeutics the study will be performed with MAVYRET because this is 
the combination most frequently being prescribed in our liver clinics at the moment] 
 
Sample Size:  Power analyses are based on detecting a difference in 2nd phase decline between the DAA 
group and the DAA+EZE group.  Pilot data of 20 patients receiving Harvoni therapy (SOF+ledipasvir) showed 
an average 2nd phase rate of decline () of 0.40/day (SD=0.1). We conservatively estimate that addition of 
EZE will increase the 2nd phase viral decline slope by ~50% and assume a conservative common standard 
deviation of 0.2 in both groups. To achieve 80% power in detecting a significant difference in slopes, using 
a two-sample t-test with α=0.05, we need to enroll 19 individuals in each group after accounting for 10% 
attrition which may include drop out or rapid response preventing 2nd phase viral decline analysis. 
 
Patient Screening: We will identify patients potentially eligible for the study during the course of routine clinical 
care in the Hines VA liver clinics. At that time, potentially eligible patients who express an interest would be 
introduced to the Clinical Research Coordinator (CRC). The CRC will further screen candidates assessing 
the inclusion/exclusion criteria listed in the Table above and explain the study in detail to the patient to 
determine if they wish to participate and give informed consent. If any of the inclusion/exclusion data is 
missing, blood will be drawn to confirm patient eligibility before their information is sent to the study 
designated HCV Clinical Pharmacy Specialist for randomization. 
 
Study Design: Chronically HCV infected patients undergoing MAVYRET treatment as part of their routine 
clinical care will be randomized 1:1 to 3 arms (n=19) of 0, 20, or 40 mg per day of EZE for the duration of 
their prescribed standard of care treatment. All subjects will have routine laboratory monitoring for patients 
receiving MAVYRET (e.g.CBC, CMP, PT/INR, and HCV RNA) plus additional research blood draws and 
laboratory testing as needed. For all subjects, HCV RNA will be measured at baseline. Subjects will then 
receive EZE or a placebo for the duration of their prescribed treatment with frequent viral kinetic 
measurements. Post-treatment SVR12 will be obtained for clinical purposes and serve to assess for viral 
rebound. Safety assessments during therapy will include history with symptom assessment, physical 
examinations and laboratories including CBC, complete metabolic panel, creatine phosphokinase (CPK), 
Prothrombin Time and International Normalized Ratio (PT/INR), and fasting lipid panel.  
 
Patients will be randomized 1:1 for treatment with 0, 20, or 40 mg per day of EZE   
  Group 1 –MAVYRET + placebo (n=19):  
  Group 2 –MAVYRET + 20 mg/day EZE (n=19); Subjects will receive a 10 mg oral dose of EZE twice daily 

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  Group 3 –MAVYRET + 40 mg/day EZE (n=19); Subjects will receive a 10 mg oral dose of EZE twice daily 
 
Laboratory Monitoring: All study required laboratory monitoring is indicated, however in some cases this 
might overlap with clinical care. All laboratory monitoring will be performed at Hines Outpatient Laboratory:  
 
Baseline laboratories (i.e., at treatment initiation; t=0):  
 
CBC (e.g. RBC, WBC, hemoglobin, hematocrit, platelets, neutrophil count) 
 
Complete metabolic panel  
(e.g. Alb, BUN, Ca, CO2, Cl2, creatinine, glucose, K, Na, bilirubin, total protein, ALT, ALP, AST) 
 
Fasting lipid panel (e.g. Tot Cholesterol, triglycerides, HDL, LDL, VLDL) 
 
Creatine phosphokinase (CPK) 
 
Prothrombin Time and International Normalized Ratio (PT/INR) 
 
HCV RNA 
 
Urine pregnancy test for childbearing age women. 
  
Serial laboratories: 
 
HCV RNA at: 
o 
24, 48, 72 hours during treatment 
o 
1, 2, 3, 4, 8 weeks  
o 
3 and 6 months post-treatment  
 
Lipid testing at weeks: (test added for research purposes) 
o 
4 and 8 weeks during treatment 
o 
3 and 6 months post-treatment  
 
CBC, CPK, PT/INR and CMP 
o 
4 and 8 during treatment (extra CPK also at 2 weeks) 
o 
3 and 6 months post-treatment  
 
Urine pregnancy test every 4 weeks in women of childbearing potential 
 
Additional labs drawn based on clinical indications 
 
Study Endpoints: 
 
1) 2nd phase slope of viral decline;  
     
  
2) Mean time to HCV RNA negativity 
     
 
3) Number and severity of adverse events during EZE therapy. 
 
Data Collection and Management. Study data will be collected using case record forms (CRFs) and 
subsequently entered into a secure online database (e.g., Research Electronic Data Capture, i.e., 
REDCap).  Demographic data (e.g. age, sex, race), concurrent medication, HCV history, and information 
regarding relevant co-morbidities (e.g. cirrhosis, fibrosis, BMI, hyperlipidemia, hypertension) will be extracted 
from the patient electronic medical record. The collected data may also be transferred from REDCap to an 
encrypted SAS file for subsequent data analysis after all data entry is complete. 
 
Patient tracking and Study Coordination. The precise details for patient tracking involve coordination among 
the CRC, the HCV Clinical Pharmacist Specialist, and the physician, but the overall tracking plan will include 
the following essential elements: 
 
- 
Medications (The Hines research pharmacy has an SOP for drug management and record keeping.   
They have a dispensing form to keep a perpetual inventory and patients return unused study 
medication to assess compliance.)   
o Initial randomization (www.randomization.com) 
o Performing pill counts at each Pharmacy visit 
o Dispensing of study medication at each Pharmacy visit 
o Record keeping 
- 
Clinical Visits 
o 
Scheduling visits 
o Making call reminders 
o Organizing research visit blood draws and filling out CRFs 
o Processing an aliquot of blood for onsite banking (for research laboratory tests) 
o Sending blood out for research-related clinical laboratory tests 
 
Follow-up assessment      

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Patient will be seen in clinic and monitored clinically for signs of drug safety issues. The clinical assessment 
is based on symptoms, significant alterations in laboratories and efficacy of treatment. Symptoms of a general 
drug adverse events might include profound fatigue, muscle aches, headaches, insomnia, severe diarrhea, 
rash, altered mental status, or hepatic decompensation (i.e., ascites, hepatic encephalopathy or variceal 
bleeding). Specific indications for EZE discontinuation include: 
 
Intolerance to ezetimibe or a clinically significant therapy-related adverse event. 
 
ALT or AST increase to >3x baseline or >10x ULN 
 
Total bilirubin >3 mg/dl in absence of evidence of Gilbert’s syndrome 
 
Muscle symptoms and a CPK level >5 x ULN 
 
An sustained increase in HCV RNA > 1 log 
 
Any unrelated hospitalization which the treating physician believes continued EZE use might be 
detrimental. 
 
Data Analysis: Serum HCV RNA will be determined by clinical quantitative RNA testing. The mean log drop 
between groups at different time post-treatment will be compared using a two-sided Wilcoxon Rank Sum 
Test or Student T-test, as appropriate. To compare categorical variables, we will use two-tailed Fisher Exact 
and Pearson Chi-Square Tests. We expect a biphasic decline in viral load during DAA and DAA+EZE 
therapy.  Based on univariable results, a multivariable (semi-parametric) linear mixed effects spline model, 
with change points modeled at time of intervention and/or transition to phase 2 via cubic smoothing splines, 
will be considered to assess decline in HCV RNA over time between the two groups.  Moreover, Kaplan-
Meier methods will be used to assess differences in time to HCV RNA negativity with individuals who do not 
achieve negativity in the study window right censored.  Based on univariable results, a multivariable cox-
proportional hazards model may be considered to adjust for important confounders.  All analyses will follow 
the intent-to-treat principle and missing data will be assumed missing at random.  Mathematical modeling: 
HCV RNA data including the first viral load below the limit of quantification (<15 IU/ml) or below the limit of 
detection will be used for model fits, using a population approach - subsequent observations (expected to be 
below the limit of detection) will be truncated. In order to accurately estimate the model parameters, we will 
exclude subjects with less than 2 samples above the limit of quantification during the 2nd phase. The viral 
clearance rate constant will be fixed to c=6/day as currently assumed in our other ongoing modeling 
efforts[18,19]. The population parameters: baseline viral load,  and  and their inter-individual variability (IIV) 
estimates will be obtained using a maximum-likelihood method implemented in MONOLIX version 4.3.2 
(Lixoft, Orsay, France), which uses the SAEM algorithm. The model is fit to log10 viral load. Patients’ baseline 
characteristics (such as patient type treatment naïve vs. non-responder) will be included as covariates in the 
model to study their effect on the parameters. Individual parameters will be estimated using the empirical 
Bayes method[20] .  
 
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