Conditions: Hepatitis B
Keywords: Emtricitabine Tenofovir Antiviral Therapy Hepatitis B HBV
Allocation: RANDOMIZED | Intervention model: PARALLEL
Enrollment: 35
Healthy volunteers: no

Brief summary:
This study will test whether the combination of two medications, tenofovir and emtricitabine, are safer and more effective for treating chronic hepatitis B than tenofovir alone. Chronic hepatitis B is a liver disease caused by infection with the hepatitis B virus. Several medications, including standard and pegylated interferon and the anti-viral drugs lamivudine, adefovir, entecavir and telbivudine, are currently used to treat the disease. Problems are associated with all of these agents, however, including development of viral resistance with long-term therapy of the anti-virals. Since many patients require long-term therapy to prevent their disease from worsening, a major goal of new approaches to treatment is to prevent the development of viral resistance. Combination treatment has been shown to be an effective strategy in preventing this resistance.

Tenofovir is an anti-viral drug approved for use in patients with HIV infection. In small studies in patients infected with both HIV and hepatitis B, tenofovir lowered the level of hepatitis B virus in the blood, with no viral resistance reported when used for up to 5 years. Emtricitabine is an anti-viral drug similar to lamivudine and is effective at lowering viral load and improving liver damage.

Patients 18 years of age and older with chronic hepatitis B may be eligible for this study. Participants are admitted to the NIH Clinical Center for a complete medical history and examination, including blood and urine tests, chest X-ray, electrocardiogram, abdominal ultrasound, Fibroscan (ultrasound exam of the liver that measures the amount of scarring), bone mineral density scan and liver biopsy. They are then randomly assigned to take combination treatment with tenofovir plus emtricitabine or tenofovir alone for at least 48 weeks. During the treatment period, patients visit the Clinical Center for blood tests and a physical examination every 2 weeks for the first month and then every 4 to 12 weeks. After 48 weeks, patients are readmitted to the Clinical Center for a complete evaluation that includes all the tests done at the start of therapy, including a liver biopsy. Patients who seem to have improved with treatment may continue therapy for up to 192 weeks, when they are again admitted to the Clinical Center for a complete medical evaluation and liver biopsy. Patients whose condition has not improved after 48 weeks of treatment have their treatment changed or stopped and continue to have regular outpatient clinic visits for 24 more weeks.

Detailed description:
Chronic hepatitis B is a major cause of cirrhosis, end-stage liver disease and hepatocellular carcinoma and affects approximately 1.25 million Americans. Six medications have been licensed for use in chronic hepatitis B in the United States, but their relative benefit and long-term efficacy remain unclear. In previous studies, we have shown that maintained suppression of hepatitis b virus DNA (HBV DNA) can be achieved with nucleoside analogues and that suppression is associated with marked improvements in disease. In this randomized study, we propose to evaluate long-term therapy with tenofovir alone or in combination with emtricitabine (FTC). Forty treatment-naive patients with chronic hepatitis B will be enrolled in the primary study. After medical evaluation and liver biopsy, patients will be stratified by hepatitis B e antigen (HBeAg) status and randomized to receive either tenofovir alone or in combination with FTC. Treatment will be continued long-term (at least four years) and patients will be carefully monitored for side effects, serum aminotransferase and HBV DNA levels. Patients will undergo repeat liver biopsy and assessment of antiviral resistance at 1 and 4 years. The primary endpoint of therapy will be the maintained suppression of HBV DNA to below 10(2) copies/ml (lower limit of detection of current assays). The study will assess the relative efficacy and safety of combination versus mono-therapy. A separate group of 60 previously treated patients will also be enrolled and randomized to mono- or combination-therapy to assess the safety profile of these agents. The primary analysis will be conducted on the entire study cohort.

Arms:
arm 1: Tenofovir 300mg by mouth daily for 192 weeks arm 2: Tenofovir 300mg in combination with emtricitabine 200mg by mouth daily for 192 weeks

Interventions: intervention 1: Tenofovir & Emtricitabine intervention 2: Tenofovir
Intervention descriptions: intervention 1: None intervention 2: None

Protocol document:
Prot_SAP_000.pdf: 
CLINICAL RESEARCH PROTOCOL 
 
NATIONAL INSTITUTE OF DIABETES AND DIGESTIVE AND KIDNEY DISEASES 
 
DATE: November 2, 2016 
 
 
CLINICAL PROTOCOL NO.: 07-DK-0207 
 
          
 
 
 
 
 
IND NO: 78,112 
 
 
  
        
 
  
 
 
 
 
IND Name: Tenofovir, Emtricitabine 
          
 
 
 
 
 
IND HOLDER: Marc G. Ghany 
 
TITLE:  Tenofovir Disoproxil Fumarate Alone Versus its Combination with 
Emtricitabine for Treatment of Chronic Hepatitis B  
 
SHORT TITLE: Tenofovir and Emtricitabine for Hepatitis B 
 
IDENTIFYING WORDS: Tenofovir disoproxil fumarate, Emtricitabine, FTC, 
Nucleoside/Nucleotide analogue, Chronic Hepatitis B, Hepatitis B mutants, Liver Biopsy.  
 
PRINCIPAL INVESTIGATOR: Marc Ghany, M.D., Liver Diseases Branch (LDB), 
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)* 
 
 
ASSOCIATE SENIOR INVESTIGATORS:   
T. Jake Liang, M.D., Chief, LDB, NIDDK* 
Barbara Rehermann, M.D., Senior Investigator, LDB, NIDDK 
Edward Doo, M.D., LDRB, Division of Digestive Diseases and Nutrition, NIDDK* 
Theo Heller, M.D., Investigator, LDB, NIDDK* 
Yaron Rotman, M.D. Staff Physician, LDB, NIDDK* 
Christopher Koh, M.D. Investigator ,LDB,NIDDK* 
Libby Wright, Ph.D. OD, NIDDK 
David Kleiner, M.D., PhD., Laboratory of Clinical Pathology, NCI 
 
ASSOCIATE STAFF INVESTIGATORS:  
Ahmad Alawad, M.D. Medical Staff Fellow, LDB, NIDDK* 
Devika Kapuria, M.D. Medical Staff Fellow, LDB, NIDDK* 
Varun Takyar, M.D. Medical Staff Fellow, LDB, NIDDK* 
Gil Ben-Yakov, M.D., Medical Staff Fellow, LDB, NIDDK* 
Elenita Rivera, R.N., Clinical Research Nurse, LDB, NIDDK 
Nancy Fryzek, R.N., Clinical Research Nurse, LDB, NIDDK 
Vanessa Haynes-Williams, R.N., Clinical Research Nurse, LDB, NIDDK 
Amy Huang, R.N., Clinical Research Nurse, LDB, NIDDK 
 
*Investigators with this designation are authorized to obtain informed consent for this 
protocol. 
 
 


 
2 
ESTIMATED DURATION OF STUDY: 12 Years 
 
ANTICIPATED STUDY END DATE: 2019 
NUMBER AND TYPE OF PATIENTS: 100 patients with chronic hepatitis B, ages 
above 18 years, both male and female 
SUBJECTS OF STUDY:    Number      
Sex           
          Age Range 
Patients               
 
100  
   Male & Female              Above 18 years 
Volunteers             
          None 
PROJECT USES IONIZING RADIATION:  Yes, for medical indications only. 
PROJECT USES "DURABLE POWER OF ATTORNEY":  No 
OFF-SITE PROJECT: No       MULTI-INSTITUTIONAL PROJECT:   No 


 
3 
Précis 
 
Chronic hepatitis B is a major cause of cirrhosis, end-stage liver disease and 
hepatocellular carcinoma and affects approximately 1.25 million Americans.  Six 
medications have been licensed for use in chronic hepatitis B in the United States, but 
their relative benefit and long-term efficacy remain unclear.  In previous studies, we have 
shown that maintained suppression of HBV DNA can be achieved with nucleoside 
analogues and that suppression is associated with marked improvements in disease.  In 
this randomized study, we propose to evaluate long-term therapy with tenofovir alone or 
in combination with emtricitabine (FTC).  Forty treatment-naive patients with chronic 
hepatitis B will be enrolled in the primary study.  After medical evaluation and liver 
biopsy, patients will be stratified by hepatitis B e antigen (HBeAg) status and randomized 
to receive either tenofovir alone or in combination with FTC. Treatment will be 
continued long-term (at least four years) and patients will be carefully monitored for side 
effects, serum aminotransferase and HBV DNA levels.  Patients will undergo repeat liver 
biopsy and assessment of antiviral resistance at 1 and 4 years.  The primary endpoint of 
therapy will be the maintained suppression of HBV DNA to below 102 IU/ml (lower limit 
of detection of current assays).  The study will assess the relative efficacy and safety of 
combination versus mono-therapy. A separate group of 60 previously treated patients will 
also be enrolled and randomized to mono- or combination-therapy to assess the safety 
profile of these agents. The primary analysis will be conducted on the entire study cohort. 
 
[Word count = 250]


 
4 
Background 
 
Chronic Hepatitis B and its Therapy: 
 
Chronic hepatitis B is a major cause of chronic liver disease, cirrhosis and hepatocellular 
carcinoma affecting close to 400 million persons worldwide. In the United States an 
estimated 1.25 million persons are chronically infected with the hepatitis B virus 
(HBV).1,2 
 
Currently there are six therapies approved by the Food and Drug Administration (FDA) 
for chronic hepatitis B including: interferon alfa-2b, peginterferon alfa-2a, lamivudine, 
adefovir dipivoxil, entecavir and telbivudine.3 All licensed therapies have been shown to 
be superior to placebo and both entecavir and telbivudine have been shown to be superior 
to lamivudine using several parameters to assess outcome, including: histological 
improvement (defined as improvement in necroinflammatory score by two or more points 
with no worsening of fibrosis), suppression of HBV DNA to undetectable levels by 
sensitive, polymerase chain reaction (PCR)-based assays, and normalization of serum 
alanine aminotransferase levels.4-12 Additionally, in HBeAg-positive patients, higher rates 
of HBeAg loss and HBeAg seroconversion were observed in active treatment arms. 
Long-term follow-up studies have shown that a defined course of therapy with interferon 
and long-term treatment with lamivudine are associated with lower rates of cirrhosis, 
hepatocellular carcinoma and death.13-15  
 
Despite these successes, current therapy remains less than optimal due to low rates of 
HBsAg loss, high relapse rates, the need for long-term therapy and subsequent 
development of antiviral resistance. The optimal regimen has not been defined: which 
agent/s to use, for how long and in which patients.16-22  Therapy with any of the six 
agents for one year leads to sustained improvements in only a small proportion of 
patients. Among HBeAg-positive patients, between 17% and 33% of patients become 
HBeAg negative on therapy and therefore are candidates for withdrawal of therapy. Of 
these, relapse (reappearance of HBeAg in serum) may occur in up to 50% of patients 
necessitating reinstitution of therapy.3,23 In patients who do not become HBeAg negative 
and in persons with HBeAg-negative chronic hepatitis B, the majority (~90%) relapse 
when therapy is stopped.    
 
Long-term antiviral therapy of hepatitis B is possible with nucleoside analogues 
(lamivudine, adefovir, entecavir and telbivudine), but is impractical with interferon or 
peginterferon because of their frequent side effects. Several small studies have shown 
that extending therapy using the oral nucleoside analogues is associated with improved 
rates of HBeAg loss, maintained suppression of HBV DNA and improvements in both 
biochemical and histological features of disease.24-28 However, these beneficial effects are 
often negated by a parallel increase in rates of viral resistance.29  The rate of viral 
resistance varies among the various agents.  With lamivudine monotherapy, rates of viral 
resistance increase from 14-24% at year 1 to approximately 70% by years 4 to 5.  
Similarly, recent data on long-term use of adefovir reports rates of resistance that increase 
from 2% at 2 years to 29% at 5 years. Resistance has been reported in <1% with entecavir 


 
5 
use in nucleoside analogue-naïve patients at three years but reaches 15% at three years in 
those with a history of lamivudine resistance.30,31  
 
Continuation of therapy after the development of resistance is associated with loss of 
clinical response in the majority of patients.25 Furthermore, development of resistance 
makes subsequent therapy difficult.29,30 While both adefovir and entecavir have activity 
against lamivudine resistance HBV mutants, this activity is relatively reduced and the 
presence of lamivudine resistance appears to increase the rate of resistance to adefovir 
and entecavir.  Treatment options for managing antiviral resistance are limited and the 
preferred strategies include adding a second agent or switching therapy. Decompensation 
and/or death have been associated with stopping therapy, especially in those with 
advanced liver disease and these patients need to be monitored closely.32 A small 
minority of patients may continue to have clinical improvement compared to baseline 
values but the disease continues to worsen in the majority of patients.25  
 
Post-hoc analyses of several treatment trials suggest that sustained suppression of HBV 
DNA to low levels (at least <104 and preferably to < 102) is associated with improved 
biochemical and histological outcomes and should be the primary surrogate goal of 
antiviral therapy. Maintained, long-term suppression of HBV DNA correlates well with 
observed clinical outcomes. Suppression of HBV DNA by oral nucleoside analogues 
(lamivudine) has also been shown to restore the HBV-specific CD4 and CD8 T cell 
responsiveness, which is typically weak in chronic hepatitis B.33-35 Restoration of HBV-
specific T cell responses was transient,35,36 however, and recurring decreased T cell 
responsiveness during prolonged therapy was associated with increased prevalence of 
lamivudine-resistant HBV mutants and increased HBV titers.35 Thus, treatment strategies 
are needed to improve long-term, sustained anti-viral efficacy as well as prevention of 
antiviral resistance. An attractive option borrowing from the HIV paradigm is to treat 
patients with drug combinations, using agents with different mechanisms or sites of 
action.  This approach might be beneficial in both preventing resistance as well as 
heightening antiviral activity (through synergy or additive antiviral activity).  However, 
results of trials of combination therapy in chronic hepatitis B have been disappointing. 
 
Combination Therapy of Chronic Hepatitis B 
 
There have been several prospective studies comparing the combination of interferon (or 
peginterferon) and nucleoside analogues (usually lamivudine) to either agent alone.8,9,37 
These studies have demonstrated that there is improved viral suppression (partial additive 
activity) and that lamivudine resistance is less common when it is combined with 
interferon, however sustained response rates have not been higher with combination 
therapy compared to interferon (or peginterferon) monotherapy. The most recent, large 
scale study evaluated one-year courses of therapy in HBeAg-positive patients and long-
term response rates after peginterferon monotherapy as well as after peginterferon and 
lamivudine combination therapy and combined were in the range of 30 to 35%.8  Thus, 
combination of interferon and nucleoside analogues appears to result in additive antiviral 
activity and some degree of delay in development of antiviral resistance, but when given 
in one year courses, combination therapy appears no more effective than monotherapy 


 
6 
with interferon alone. Long-term combination therapy has not been pursued because of 
the systemic side effects of interferon. 
 
In contrast to interferon, the oral nucleoside analogues are very well tolerated and have 
few if any side effects in most patients, making long-term administration of these agents 
practical.  There have, however, been few prospective trials comparing monotherapy with 
nucleoside analogues to combination therapy and none that have analyzed long-term 
results.  Most combination studies have been conducted in patients with lamivudine 
resistance or conducted for short periods (4 to 12 months).38-40  However, these studies 
have shown that combination of two nucleosides does not appear to increase antiviral 
activity; that the degree of viral suppression matches that of the most potent agent.  Thus, 
when adefovir was used to treat patients with lamivudine resistance, the degree of HBV 
DNA suppression and loss of HBeAg was similar in patients switched to adefovir 
(monotherapy) to those in whom adefovir was added to lamivudine (combination 
therapy).38  Furthermore, when patients were treated with telbivudine (LdT, a potent 
lamivudine-like nucleoside analogue) alone, lamivudine alone or the combination of 
telbivudine and lamivudine, the degree of HBV DNA suppression was the same with 
telbivudine alone as with the combination.39,40  
 
The Liver Diseases Branch of NIDDK has been conducting prospective studies of long-
term therapy of chronic hepatitis B with nucleoside analogues since 1995.  The first study 
(95-DK-199) enrolled 42 patients with chronic hepatitis B (22 with HBeAg-positive, 20 
with HBeAg-negative infection).25   At one year, a majority of patients showed evidence 
of clinical improvement –in HBV DNA levels, ALT elevations and liver histology.  
However, the rate of antiviral resistance was high, reaching 25% by one year and 
ultimately 75% in HBeAg positive and 50% in HBeAg-negative patients.  Patients 
enrolled in this study have continued to be followed and those still receiving lamivudine 
monotherapy have been enrolled in a long-term study (05-DK-0195).  As of September 
2006, only five of the initial 22 HBeAg-positive patients continue to have a maintained 
virological response (HBV DNA levels < 104 IU/ml) to lamivudine monotherapy.  The 
remaining 17 HBeAg-positive patients required therapy with other agents (peginterferon 
or adefovir) because of failure of lamivudine and evidence of progressive disease.  
Importantly, the 5 patients with a maintained virological response all had marked 
improvement in liver histology, normalization of ALT elevations, and loss of HBeAg.  In 
addition, 3 of the 5 have become HBsAg-negative and have been able to stop lamivudine 
therapy without evidence of relapse in follow up (for 0.5, 6 and 7 years).  Among the 20 
HBeAg-negative patients in that initial study, 16 continued on lamivudine monotherapy 
and 15 have a maintained response (HBV DNA <104), normal ALT levels and improved 
histology.  In this cohort, 4 have become HBsAg-negative and have been able to stop 
lamivudine therapy without relapse.  The 5 HBeAg-negative patients who failed to have a 
maintained response on lamivudine monotherapy included one who was lost to follow up 
(returned to Iran), one who underwent liver transplantation (and is alive and without 
HBsAg on long-term lamivudine provided by her transplant physicians), one who died of 
end-stage liver disease (with lamivudine resistance and intolerance to adefovir due to 
renal disease), one who is on lamivudine but has viral levels above 104 (with normal 
serum aminotransferase levels) and one who is currently on adefovir (and has a 


 
7 
maintained response with no detectable HBV DNA and normal ALT levels).  These 
results, while based on few patients, demonstrate that the rate of resistance to lamivudine 
monotherapy is unacceptably high (particularly in HBeAg-positive patients) but that 
maintained suppression of HBV DNA <104 IU/ml is associated with marked 
improvements in serum biochemical abnormalities and liver biopsy.  Furthermore, long-
term suppression of HBV DNA to <102 IU/ml can be followed by loss of HBsAg in a 
moderate proportion of patients.  Loss of HBsAg is associated with resolution of the 
chronic hepatitis and permits discontinuation of therapy.    
 
These findings led to a second study that started in 2001 and was a prospective, 
randomized trial of adefovir monotherapy versus the combination of adefovir and 
lamivudine (01-DK-246).  This study did not include a lamivudine monotherapy arm 
because of the historical information available on lamivudine monotherapy and the 
unacceptable rate of antiviral resistance from that and other studies.25,29  At the time that 
this study was initiated, adefovir had been shown to be effective against hepatitis B and 
no instances of adefovir resistance were reported.  In the interim, it is clear that adefovir 
resistance does occur, but generally only after 1 to 2 years of therapy, reaching 2% at 2 
years, 18% at 4 years and 29% at 5 years.27,41  Thus, studies of adefovir for one-year only 
are inadequate to assess the rate or prevention of resistance and the overall rate increases 
gradually thereafter, although 10 year results have yet to be reported. 
 
Results of our study of adefovir have yet to be published, but 39 patients have been 
enrolled including 26 HBeAg-positive patients who have been treated for at least one 
year. Twenty subjects were randomized to the combination of lamivudine and adefovir 
and nineteen to adefovir monotherapy. Thirty-one subjects have completed one year of 
therapy, 26 HBeAg-positive patients including 27 males, mean age 45 years, 10 of whom 
were previously treated and had lamivudine resistance. Four patients had cirrhosis at 
baseline. Undetectable HBV DNA by PCR was observed in 75% of patients receiving 
combination therapy versus 47% receiving monotherapy. Sixty-nine percent and 86% of 
patients receiving combination therapy had normalization of ALT and a histological 
response compared to 47% and 67% respectively receiving monotherapy. Primary non-
response defined as <3 log10  HBV DNA reduction at 24 weeks was observed in 6 of 15 
(40%) patients randomized to adefovir but in no patient randomized to combination 
therapy. Among the treatment naïve cohort who extended therapy, long-term suppression 
of HBV DNA to <104 IU/ml could be achieved in 100% of patients receiving the 
combination of adefovir and lamivudine (14 of 14 patients) but in only 44% (5 of 12) of 
patients receiving adefovir alone.  Furthermore, among previously untreated patients with 
HBeAg-positive disease, combination therapy was associated with loss of HBeAg and no 
detectable HBV DNA (<102 IU/ml) in 9 of 10 patients at the time of their last clinic visit.  
Failure of adefovir therapy occurred early, during the first year of treatment, and was not 
associated with classical adefovir resistance, but rather with apparent suboptimal antiviral 
activity, levels of HBV DNA never falling below 106 IU/ml. After a full year of 
treatment, patients who failed to respond to adefovir monotherapy were switched to 
combination therapy.  Striking, all four patients who were switched to combination 
therapy and have had a full year of treatment have failed to have an adequate response, in 
that all four still have HBV DNA levels above 104 IU/ml and elevations in serum ALT 


 
8 
levels.  This latter result was unexpected and disturbing, as it appears to show that 
combination therapy is more effective than monotherapy only if started initially.  Thus, a 
clinically attractive approach to therapy of treating all patients with monotherapy and 
switching those who fail treatment to combination therapy may not be as effective as 
starting with combination therapy.  While based upon small numbers, the results of this 
trial have led us to plan to initiate a new study using tenofovir (an agent similar to 
adefovir but more potent) comparing tenofovir monotherapy to the combination of 
tenofovir and emtricitabine (FTC: an agent similar to lamivudine) in chronic hepatitis B.  
 
Why tenofovir?  And why FTC rather than lamivudine? 
 
Tenofovir disoproxil fumarate is an acyclic nucleotide analogue that is structurally 
related to adefovir dipivoxil and shows overlap in mechanism of HBV DNA inhibition 
and in antiviral resistance patterns with adefovir.29  In vitro tenofovir has a similar 
potency as adefovir, but in small human studies appears to be ~30 more potent than 
adefovir perhaps due to the higher dose administered.42-44 The side effect profile and 
safety of tenofovir (given in doses of 300 mg once daily) is similar to that of adefovir 
(given in doses of 10 mg daily). Tenofovir is FDA-approved for therapy of HIV infection 
and is widely used in situations of HIV infection with multiple resistance patterns. 
Recently, a series of small studies has shown that tenofovir has potent activity against 
hepatitis B and has been used to rescue patients with end-stage liver disease in both 
lamivudine- and adefovir-resistant HBV and after liver transplantation.45  
 
Adefovir and tenofovir were directly compared in a retrospective case series in 53 
patients with lamivudine resistance and HBV DNA levels above 106 IU/ml.  The study 
was not randomized, but 35 patients received tenofovir and 18 received adefovir, therapy 
lasting for more than one year.42  HBV DNA levels fell more rapidly in tenofovir- than 
adefovir-treated patients and after 28 weeks, all patients who received tenofovir had HBV 
DNA levels < 105 IU/ml compared to only 44% of adefovir-treated patients. No patient 
developed tenofovir resistance, and only rare case reports of tenofovir resistance have 
been reported despite extensive use of this agent, particularly in HIV-HBV co-infected 
individuals. Side effects were also uncommon. Tenofovir shares a pattern of renal 
toxicity with adefovir, a side effect that is observed largely in patients with pre-existing 
renal disease or in those who are treated with higher doses of these agents. Additionally, 
the majority of HIV-HBV co-infected individuals who developed renal toxicity were also 
receiving ritonovir, the combination of lopinavir or ddI which may increase proximal 
renal tubular concentrations of tenofovir and increase the risk of renal toxicity. 
 
Tenofovir has also been used to treat patients who fail to respond to adefovir.  In a recent 
study, 20 patients with chronic hepatitis B (19 HBeAg-positive) and lamivudine 
resistance who failed to respond to a 4 to 28 month course of adefovir monotherapy were 
switched to tenofovir.  All patients had a subsequent decrease in HBV DNA and 19 
became HBV DNA negative by PCR (<103).43 
 
We have experience with treating 7 patients with tenofovir who failed to respond 
adequately to lamivudine or the combination of lamivudine and adefovir. All seven 


 
9 
patients became HBV DNA negative (<102 IU/ml) with decrease in serum ALT levels to 
normal within 24 weeks.  No toxicity or side effects were noted.  Thus, tenofovir is a 
promising oral nucleotide analogue with potent activity against hepatitis B and a low rate 
of toxicity and resistance.  The sponsor of tenofovir (Gilead Sciences) is currently 
conducting a multicenter randomized controlled trial in chronic hepatitis B with the 
intention of obtaining FDA approval for this indication.  
 
Five year continuous therapy with tenofovir with viral suppression has been associated 
with histological improvement including reversal of fibrosis and cirrhosis.46 Long-term 
histological data was reported on 348 patients with paired biopsy results from baseline 
and week 240 of therapy. This cohort represents about half of the cohort who were 
enrolled in the phase 3 trial. 304 (87%) of the 348 had histological improvement, and 176 
(51%) had regression of fibrosis at week 240 (p<0·0001).46 Of the 96 (28%) patients with 
cirrhosis (Ishak score 5 or 6) at baseline, 71 (74%) no longer had cirrhosis (≥1 unit 
decrease in score), whereas three of 252 patients without cirrhosis at baseline progressed 
to cirrhosis at year 5 (p<0·0001).46  
 
Emtricitabine (FTC) is a cytosine analogue with potent in vitro and in vivo activity 
against hepatitis B.47  FTC is similar to lamivudine (3TC) and has a similar profile of 
activity and viral resistance.  Thus, FTC has little activity against lamivudine resistant 
strains of HBV and FTC-resistance is associated with similar mutations in the HBV 
polymerase gene as occur with lamivudine therapy (rtM204I/V and rtL180M).  FTC was 
evaluated in a randomized controlled trial comparing a 48-week course of FTC (200 mg 
daily) to placebo in cohorts of HBeAg-positive and HBeAg-negative patients.48  In this 
study, the average suppression of HBV DNA (4.5 log10 IU/ml) and rate of clearance of 
HBeAg (14%) was similar to that reported for lamivudine.  Side effects were few and the 
major complication was withdrawal of FTC therapy after a year, which was associated 
with transient flares in disease activity in 23% of patients and one patient suffered a 
severe flare of disease and required liver transplantation.  Similar instances of life-
threatening flares of hepatitis after withdrawal of lamivudine have been reported.8,37  At 
present, FTC is approved for use in HIV infection but has yet to be approved for the 
indication of chronic hepatitis B. Thus, FTC appears to be a lamivudine-like agent with a 
similar pattern of antiviral activity, resistance and side effects. 
 
The combination of tenofovir and FTC has been evaluated in HIV infection and is 
approved for use under the trade name “Truvada”.49,50  Indeed, this combination is widely 
used as a convenient single, once-a-day treatment for HIV infection.  The activity of 
Truvada against hepatitis B is well established and this combination is an attractive 
approach to the treatment of patients with HIV-HBV co-infection.  The combination of 
tenofovir and FTC has yet to be formally assessed in patients with chronic hepatitis B 
without HIV infection.  The drug sponsor (Gilead Sciences) has planned a limited study 
in patients with chronic hepatitis B and high levels of HBV DNA, but this trial has yet to 
be initiated.   
 
In this protocol, we plan to evaluate the relative efficacy and safety of tenofovir 
monotherapy versus the combination of tenofovir and emtricitabine (Truvada) as long-


 
10 
term maintenance therapy for patients with chronic hepatitis B (both HBeAg-positive and 
-negative). The results of this trial will be compared to historical controls from a NIH 
trial evaluating the combination of lamivudine and adefovir versus adefovir monotherapy 
and published multicenter randomized control trials of lamivudine and adefovir for 
HBeAg positive chronic hepatitis B. The primary endpoint of this trial will be a 
maintained suppression of HBV DNA below 102 IU/ml and secondary endpoints will be 
normalization of serum ALT levels and improvement in histological features of chronic 
hepatitis. A separate group of patients will be treated with either tenofovir alone or 
tenofovir and emtricitabine as a “salvage” protocol for patients who have received 
nucleoside analogue therapy and have failed to have complete viral suppression despite at 
least 48 weeks of therapy or who have relapsed following withdrawal of therapy.  This 
“salvage” arm will allow for further evaluation of safety and viral suppression and will be 
used in the primary analysis of response to tenofovir monotherapy vs. combination 
therapy of tenofovir and emtricitabine.   
 
 
 
 
Hypotheses and Issues:  This protocol will address the following questions. 
 
Treatment naïve patients: 
 
1. Will combination therapy using tenofovir and emtricitabine have superior 
antiviral effects against HBV compared to tenofovir alone?  To address this issue, 
HBV DNA and ALT levels will be monitored frequently and both the absolute 
decrease and the slope (kinetics) of decrease will be compared.  The investigators 
believe that the patterns of decrease of HBV DNA and ALT levels will be similar 
between tenofovir and combination arms, the pattern reflecting the more potent 
activity of tenofovir and the absence of a synergy or additive effect of these two 
nucleos(t)ide analogues. 
2. Will combination therapy prevent or delay the appearance of antiviral resistance 
to tenofovir?  To address this issue, the HBV polymerase gene will be sequenced 
from all serum samples at yearly intervals that are HBV DNA positive.  Rates of 
development of mutations shown to be associated with tenofovir resistance 
(rtA194T)20 will be compared between the combination and monotherapy arms.  
The investigators believe that the rate of antiviral resistance will be low and that 
at 4 years, 20-25% of patients in the monotherapy arm but no patients in the 
combination arm will exhibit genotypic antiviral resistance.   
3. Will combination therapy yield a higher rate of beneficial response than 
monotherapy?  To address this issue, several definitions for response will be made 
and compared between the two arms.  The primary response definition will be 
absence of detectable HBV DNA by PCR-based methods (<102 IU/ml) at 48 
weeks and 192 weeks.  Secondary response endpoints will be HBV DNA levels < 
104 IU/ml at 48 and 192 weeks as well as both HBV DNA level definitions at 96, 
144 and 240 weeks and at the time of last assessment (= maintained response).  
Other secondary response endpoints will be clearance of HBeAg (among HBeAg-


 
11 
positive patients), loss of HBsAg, normalization of ALT, and improvement in 
liver biopsy histology scores using two definitions: (1) decrease of 3 points in 
histological activity index (HAI) compared to pre-treatment biopsy results with no 
worsening of fibrosis and (2) decrease of 3 points in HAI compared to pre-
treatment biopsy results and to a total HAI score of 3 or less with no worsening of 
fibrosis. The investigators believe that long-term tenofovir and emtricitabine will 
provide HBV DNA suppression response rates of greater than 90%. Non-
responders will likely be patients who are not compliant.  Thus, this study will be 
a designed to show superiority of combination therapy to monotherapy, and the 
investigators believe that this study will set the standard of care for chronic 
hepatitis B. 
4. Will long term maintenance of HBV DNA suppression result in loss of HBsAg 
and the ability to safely stop therapy?  To address this issue, patients will be tested 
for HBsAg at six monthly intervals.  Patients who become HBsAg negative will 
be withdrawn from therapy (beginning 6 months after the loss of HBsAg) and 
monitored carefully for evidence of return of HBV DNA activity or ALT 
elevations.  Relapse will lead to reinstitution of therapy.  The investigators believe 
that loss of HBsAg will occur in 5% to 10% of patients yearly, so that one-third of 
patients will be HBsAg negative by 5 years and two-thirds by 10 years.  This 
study will thus indicate whether therapy of chronic hepatitis B should be based 
upon maintained suppression of HBV DNA to undetectable levels until loss of 
HBsAg, which may occur after years of therapy.  This study may help define the 
factors that predict loss of HBsAg, or rather the duration of therapy necessary to 
achieve loss of HBsAg. 
 
Patients with previous lamivudine ± adefovir resistance: 
 
1) Will combination therapy yield a higher response rate and prevent the 
development of further resistance than monotherapy in patients with previous 
antiviral resistance (lamivudine, adefovir and entecavir)? Response will be 
defined as HBV DNA <102 IU/ml and normal ALT at 48 and 192 weeks. Samples 
of blood at yearly intervals that are HBV DNA positive will be tested for 
tenofovir (rtA194T) and emtricitabine (rtM204V/I and rtL180M) resistant 
mutations by direct sequencing. The investigators believe that the maintained 
virological and biochemical response will be higher in the combination arm 
compared to the monotherapy arm and the rate of further resistance will be lower 
at 48 and 192 weeks. 
 
Patients who relapsed after withdrawal of lamivudine, adefovir or the combination of 
lamivudine plus adefovir: 
 
1) We hypothesize that combination therapy will result in a greater proportion of 
subjects re-responding to re-institution of therapy. Response will be defined as an 
HBV DNA <102 IU/ml and normal ALT at 48 and 192 weeks. For individuals who 
experienced HBeAg sero-reversion (HBeAg negative to positive) a response will also 
include loss of HBeAg or HBeAg seroconversion again. We further hypothesize that 


 
12 
combination therapy will prevent or delay the appearance of antiviral resistance 
compared to tenofovir monotherapy in persons who relapsed? To address this issue, 
the HBV polymerase gene will be sequenced from all serum samples at yearly 
intervals that are HBV DNA positive. 
 
Protocol 
 
Up to 100 patients with chronic hepatitis B will be enrolled including at least 40 patients 
who have not been previously treated (naïve patients:  primary study) and up to 40 
patients who have received or are receiving nucleoside analogue therapy and up to 20 
patients who have relapsed following withdrawal of therapy (experienced patients: 
salvage study).  After medical evaluation and liver biopsy, patients will be randomized 
and receive either monotherapy with tenofovir (300 mg) daily or combination therapy 
with tenofovir (300 mg) and emtricitabine (FTC: 200 mg) daily.  Gilead Sciences will 
provide the combination of tenofovir and emtricitabine as a single tablet and tenofovir 
300 mg as a single tablet. Neither the investigators nor the patients will be blinded to the 
investigational agents. Patients will be followed carefully on therapy at 2 to12 week 
intervals and undergo repeat medical evaluation and liver biopsy at 48 and 192 weeks.  
Therapy will be continued indefinitely, although the randomized phase of this trial will 
last for 192 weeks only.  The definition of a successful endpoint of therapy will be the 
maintained suppression of HBV DNA below 102 IU/ml by current PCR-based assays, 
Roche Amplicor assay).  Secondary endpoints will be (2) normalization of ALT levels 
and (3) histological improvements which are expected to occur in all patients with full 
suppression of HBV DNA and in a proportion of those with partial suppression.  Other 
endpoints will be (3) loss of HBeAg and (4) loss of HBsAg.  Patients who have lost 
HBsAg will undergo a monitored withdrawal of therapy with reinstitution of treatment if 
relapse occurs.    
 
A1. Inclusion criteria: Primary Study (nucleoside analogue-naïve subjects) 
1) Age >18 years and older, male or female 
2) Known serum HBsAg positivity for 24 weeks 
3) Detectable HBV DNA >104  IU/ml. For patients with cirrhosis HBV DNA >103 
IU/ml 
4) Serum ALT or AST levels 1.5 X ULN (for ALT: >62 U/L and for AST: > 46 
U/L) based on at least two determinations taken at least one month apart during 
the 24 weeks before study entry; no ALT requirement for patients with cirrhosis  
5) Liver biopsy within 2 years of entry that is consistent with chronic hepatitis and 
with a histology activity index (HAI) score of 4 or more (scores range from 0-18) 
and an Ishak fibrosis score of at least 1 (scores range from 0-6).  For patients who 
have had a liver biopsy at another institution, slides must be obtained for reading 
and scoring at the NIH.  
6) Written informed consent 
 
A2.  Inclusion criteria: Salvage Study (nucleoside analogue experienced subjects) 
1) Age >18 years and older, male or female 
2) Known serum HBsAg positivity for 6 months 


 
13 
3) Detectable HBV DNA >102 IU/ml. 
4) Liver biopsy within 5 years of entry that is consistent with chronic hepatitis  
5) Written informed consent 
 
A.3 Inclusion criteria: Salvage Study (relapsers) 
1) Age >18 years and older, male or female 
2) Known serum HBsAg positivity for 6 months 
3) Detectable HBV DNA >103 IU/ml. 
4) Liver biopsy within 5 years of entry that is consistent with chronic hepatitis 
5) Written informed consent 
6) Serum ALT or AST levels 1.5 X ULN (for ALT: >62 U/L and for AST: > 46 
U/L) based on at least two determinations taken at least 2 weeks apart  
 
B. Exclusion criteria 
1) Previous or current treatment with tenofovir or emtricitabine. 
2) Co-infection with HDV as defined by the presence of anti-HDV in serum and/or 
HDV antigen in the liver. 
3) Co-infection with HCV as defined by the presence of HCV RNA in serum. 
4) Co-infection with HIV as defined by the presence of anti-HIV in serum. 
5) Decompensated liver disease as defined by serum bilirubin >2.5 mg/dL (with 
direct bilirubin > 0.5 mg/dL), prothrombin time of greater than 2 seconds 
prolonged, a serum albumin of less than 3 g/dL, or a history of ascites, variceal 
bleeding or hepatic encephalopathy. 
6) Presence of other causes of liver disease, (i.e. hemochromatosis, Wilson disease, 
alcoholic liver disease, nonalcoholic steatohepatitis, alpha-1-anti-trypsin 
deficiency). 
7) A history of organ transplantation or in the absence of organ transplantation, any 
immunosuppressive therapy requiring the use of more than 5 mg of prednisone (or 
its equivalent) daily. 
8) Significant systemic illness other than liver diseases including congestive heart 
failure, renal failure, chronic pancreatitis, diabetes mellitus with poor control that 
in the opinion of the investigator may interfere with therapy. 
9) Pregnancy or inability to practice contraception in patients capable of bearing or 
fathering children and lactating women. 
10) Hepatocellular carcinoma (HCC), or the presence of a mass on imaging studies of 
the liver that is suggest of HCC, or an alpha-fetoprotein level of greater than 500 
ng/mL. 
11) History of clinically apparent pancreatitis or evidence of subclinical pancreatitis 
as shown by serum amylase values twice the upper limits of the normal range and 
abnormalities of the pancreas on CT or other imaging studies of the abdomen. 
12) Sensory or motor neuropathy apparent from medical history and physical 
examination. 
13) Creatinine clearance < 50 ml/min, serum creatinine > 1.3 mg/dl or urine protein 
>1 gram/24-hours; creatinine clearance will be determined on the average of two 
24 hour urine specimens. Accuracy of collection will be ensured by documenting 


 
14 
appropriate total creatinine excretion in the 24-hour urine specimen (15 mg/kg) 
and correcting for the patient’s age, gender and body surface area. 
14) Concurrent use of nephrotoxic agents (e.g., aminoglycosides, amphotericin B, 
vancomycin, foscarnet, cis-platinum, pentamidine, nonsteroidal anti-inflammatory 
agents) or competitors of renal tubular excretion (e.g., probenecid) within 2 
months prior to study screening or the expectation that the subject will receive 
these during the course of the study. 
15) History of hypersensitivity to nucleoside analogues. 
16) Active ethanol/drug abuse/psychiatric problems such as major depression, 
schizophrenia, bipolar illness, obsessive-compulsive disorder, severe anxiety, 
personality disorder that, in the investigator’s opinion, might interfere with 
participation in the study. 
17) History of renal tubular acidosis. 
18) History of malignancy or treatment for a malignancy within the past 5 years. 
19) Presence of conditions that, in the opinion of the investigators, would not allow 
the patient to be followed in the current study for at least 5 years. 
 
C. Initial evaluation 
 
Patients will be seen in the outpatient clinic of the NIH Clinical Center and undergo the 
following evaluation before starting therapy. Patients requiring a liver biopsy will be 
admitted to the Clinical Center for a percutaneous liver biopsy under ultrasound 
guidance. 
 
1. History and physical examination. 
2. Blood tests – complete blood count (CBC with differential and platelet count), 
prothrombin time, partial thromboplastin time, sedimentation rate, Chem-20 (which 
includes alanine aminotransferase [ALT], aspartate aminotransferase [AST], direct 
and total serum bilirubin, albumin, total protein, lactic dehydrogenase [LDH] creatine 
phosphokinase [CK], sodium, chloride, bicarbonate, potassium, blood urea nitrogen, 
creatinine, uric acid, calcium, and phosphorus), alpha-fetoprotein, amylase, lipase, 
immunoglobulin G, A and M, thyroid stimulating hormone (TSH), antinuclear 
antibody (ANA), rheumatoid factor, lipid panel (triglycerides, total cholesterol, high 
density lipoprotein associated cholesterol, low density lipoprotein associated 
cholesterol), hepatitis B viral markers (HBsAg, anti-HBs, HBeAg, and anti-HBe), 
anti-HCV, anti-HDV, and anti-HIV. An additional 10 ml. of serum will be collected 
and stored at –20 degrees Celsius for future research testing.   
3. Baseline HBV DNA level by quantitative PCR (Amplicor™: Roche, lower limit of 
detection 20 IU/ml) and HBV genotyping (HBV Genotyping Line Probe Assay, 
Innogenetics, Belgium).  
4. Routine urinalysis, random total protein/creatinine ratio, and two 24-hour urines for 
creatinine clearance and protein excretion. 
5. Pregnancy test for women of childbearing potential. 
6. Patients who have not had them within the previous year will undergo chest X-ray, 
electrocardiogram (EKG), and abdominal ultrasound. 


 
15 
7. Patients will undergo percutaneous liver biopsy unless they have had one within the 
past two years that is available for analysis or have specific contraindications to liver 
biopsy. Patients with known or suspected portal hypertension (previous liver biopsy 
showing Ishak stage 5 or 6 or platelet count less than 100,000) will undergo a 
transjugular liver biopsy with measurement of the hepatic venous pressure gradient 
(HVPG). The liver biopsy will be scored by an expert hepatopathologist blinded to 
the clinical information using the Ishak modification of the histology activity index 
(HAI) for inflammation and necrosis (scores ranging from 0 to 18). A fibrosis score 
using the Ishak staging of fibrosis (0-6) will also be assigned to each liver biopsy 
specimen. Slides will also be stained for HBsAg, HBcAg, and HDV antigen by 
peroxidase-antiperoxidase techniques and scored as 0, 1, 2 or 3+ based upon the 
percent of cells reactive for each viral antigen. Liver-infiltrating T cells will be 
isolated and assessed for frequency, function and HBV-specificity by Elispot and/or 
flow cytometry.  m-RNA levels of T cell markers and chemokines/cytokines will be 
quantitated by real-time PCR. 
8. Patients identified with portal hypertension (HVPG > 5 mm Hg) will undergo upper 
endoscopy for evaluation of endoscopic varices. Management of varices will be as 
per the standard guidelines of the American Association for the Study of Liver 
Diseases. 
9. Fifty milliliters of whole blood will be drawn for baseline immunological studies:  
CD4+ and CD8+ T cell HBV specific responses. 
10. Patients will undergo an ultrasound based fibroscan that measures elasticity of the 
liver and is an indirect measure of degree of liver fibrosis. 
11. At baseline, all patients will undergo a three-phase computerized tomography of the 
abdomen to fully exclude the presence of hepatocellular carcinoma and provide a 
baseline assessment of all patients.  
12. Patients will undergo a bone mineral density scan as a baseline to monitor for bone 
loss. Patients found to have osteoporosis or osteomalacia at baseline will be offered 
therapy with bisphosphonates and calcium. 
 
D. Treatment 
 
Patients will be stratified for randomization on the basis of HBeAg status and on the basis 
of previous therapy.  The primary study will be in patients (Groups A and B) who have 
not been previously treated (treatment naïve) and who have active liver disease (based on 
ALT levels and liver biopsy) and high levels of HBV DNA (>104 IU/ml). The salvage 
study will be in patients (Groups C and D) who have received other nucleoside analogues 
and who continue to have HBV DNA detectable in serum (>102/103 IU/ml, respectively).   
A total of 100 patients will be enrolled including at least 60 patients total in Groups A 
and B and up to 40 patients in Groups C and D (previously treated).  
 
Group A: Up to 20 patients with detectable HBeAg in serum and no previous therapy 
with nucleoside analogues. 
 
Group B: Up to 20 patients without detectable HBeAg in serum and no previous therapy 
with nucleoside analogues. 


 
16 
 
Group C: Up to 20 patients who have previously received lamivudine, adefovir or 
entecavir therapy but who have persistence of HBV DNA in serum as detected by PCR-
based assay (>102 IU/ml) and HBeAg in serum for at least six months.  
 
Group D: Up to 20 patients who have previously received lamivudine, adefovir or 
entecavir therapy but who have persistence of HBV DNA in serum as detected by PCR-
based assay (>102 IU/ml) and absence of HBeAg in serum for at least six months.  
 
Group E: Up to 20 patients who have previously received lamivudine, adefovir or the 
combination of lamivudine and adefovir and who relapsed after therapy was stopped 
 
After medical evaluation, liver biopsy and informed written consent, patients will be 
randomized in double-blind fashion to receive either combination therapy with tenofovir 
and emtricitabine or mono-therapy with tenofovir. Patients with anti-viral resistance to 
lamivudine adefovir, entecavir or telbivudine or multi-drug resistance will continue on 
pre-study medication until the day of randomization. Randomization will be done by 
random numbers kept by the Pharmaceutical Developmental Service of the Clinical 
Center (A1-20, B1-20, C1-20, D1-20, E1-20). Both tenofovir (300 mg tablets) and 
Tenofovir (300 mg) / emtricitabine (200 mg) will be provided by Gilead Sciences.  A 12 
week supply of medications will be provided.  Compliance will be monitored by 
medication diaries and counting of the residual tablets returned at outpatient visits. 
 
Patients will be seen in the outpatient clinic at weeks 0, 2, 4, 8, 12, 24, 36, and 48 weeks 
during the first year of therapy and at 12 week intervals thereafter. 
 
At 48 weeks, all patients will be readmitted to the NIH Clinical Center and undergo a 
repeat thorough medical evaluation and liver biopsy.  Patients in the salvage arm will be 
excluded from undergoing the 48 week liver biopsy. Continuation of therapy thereafter 
will depend upon both tolerance and benefit. All patients will undergo a 192 week 
follow-up biopsy to assess long-term efficacy and durability of response. Benefit is 
described in Section F “Assessment of Response” and tolerance in Section G 
“Assessment of Toxicity.”   
 
The side effects will be monitored regularly. Tenofovir and emtricitabine will be stopped 
if moderate side effects attributable to either or both medications develop and persist for 
at least one week or on repeat testing. The medication(s) can be restarted if the adverse 
event resolves and does not appear to be related to either or both medications.   
  
In the absence of toxicity attributable to either agent, combination therapy with tenofovir 
and emtricitabine or monotherapy with tenofovir will be continued for 192 weeks. Study 
medication/s will be discontinued if there is serological evidence of resolution of chronic 
hepatitis B, as shown by loss of HBsAg, documented on two serum samples taken at least 
six months apart.    
 


 
17 
Patients on therapy who develop evidence of drug resistance with elevations of serum 
aminotransferase levels twice above normal and HBV-DNA levels greater than 106 IU/ml 
will be switched to alternative therapies if mutually agreed between the patient and the 
investigators. 
 
E. Monitoring  
 
Patients will be seen, interviewed, and have blood and urine tests taken at regular 
intervals according to the following schedule (Appendix A): on at least two occasions 
during the six months before treatment (Screen 1 and 2) including at the time of liver 
biopsy and initial evaluation, on day 0 (before first administration of drug) and at weeks 
2, 4, 8, 12, 24, 36, and 48 after starting therapy. Thereafter, the patients will be seen 
every 12 weeks while on therapy. At each visit, the patients will be asked about 
symptoms and possible side effects and fill out a symptom and side effect questionnaire. 
Blood samples will be drawn for CBC and biochemical tests including chemistry-20 
panel (ALT, AST, alkaline phosphatase, creatine kinase, lactic dehydrogenase, direct and 
total bilirubin, sodium, potassium, chloride, bicarbonate, glucose, BUN, creatinine, 
albumin, total protein, calcium, and phosphate), and 10 ml of research blood. HBV DNA 
will be measured at every clinical visit during therapy and more often if needed, such as 
to investigate viral breakthrough. In addition, HBsAg, HBeAg and anti-HBe will be 
tested every 12 weeks during therapy and anti-HBs if appropriate. An additional sample 
will be collected for routine storage to allow for repeat testing. Urine will be collected for 
urinalysis and random total protein/creatinine ratio at every visit. Twenty-four hour urine 
for creatinine clearance and total protein will be done at 48 weeks and 192 weeks. 
Women of child bearing potential will have a pregnancy test at each study visit. Women 
with a positive pregnancy test will be immediately withdrawn from study drug/s. Patients 
may be offered alternative approved therapy if clinically indicated. Immunological 
testing for CD4+ and CD8+ T cell responses to HBV antigens will be done before 
treatment for all previously untreated patients and repeated at 2, 4, 8, 12, 36 and 48 weeks 
for HLA-A2 positive patients. Alpha-fetoprotein levels will be measured every 24 weeks. 
Ultrasound or computerized tomography of the liver will be done every 24 weeks months 
in patients with advanced fibrosis or cirrhosis; in other patients these tests will be done at 
the time of 48 and 192 week liver biopsies. Fibroscan of the liver will be performed 
yearly. Bone mineral density will be re-assessed at 48 and 192 weeks. 
 
At the end of the initial 48 week period of treatment, patients will be readmitted to the 
NIH Clinical Center and undergo the same evaluation as outlined under initial evaluation 
above. This evaluation will include a repeat liver biopsy. Patients in the salvage arm will 
be excluded from undergoing the 48 week liver biopsy. Patients who underwent hepatic 
venous pressure gradient measurements at the start will undergo repeat pressure 
measurement with concurrent transjugular liver biopsy. Patients judged to have a 
beneficial response to therapy will be continued on tenofovir or combination therapy and 
followed at 12-week intervals. If therapy is stopped (either for toxicity, resolution of 
hepatitis B or at the end of the trial), patients will be seen in the outpatient clinic every 4 
weeks for 6 months. Thereafter, patients will be followed at 3 to 12 month intervals as is 
customary for the Liver Diseases Branch patients in protocol 91-DK-214 (“Evaluation of 


 
18 
Patients with Liver Disease”).  Patients who have not had a beneficial response or a 
sustained response will be eligible for antiviral therapy in other protocols. 
 
F. Assessment of response: 
 
In this study, the combination of tenofovir and emtricitabine and tenofovir monotherapy 
will be evaluated for long-term effects on chronic hepatitis B in both HBeAg-positive and 
-negative cohorts and in treatment naïve and those with resistance to lamivudine, 
adefovir, entecavir or all agents.     
 
Definitions: 
 
a) Full virological response: absence of detectable HBV DNA by PCR (<102 IU/ml) 
 
b) Partial virological response: suppression of HBV DNA to <104 IU/ml but >102 
IU/ml 
 
c) Serological response (HBeAg-positive patients only): loss of detectable HBeAg. 
 
d) Full biochemical response: fall of serum ALT into the normal range (<41 IU/L) 
 
e) Partial histological response: improvement in liver histology as defined by a 
decrease in the inflammatory component of the histological activity index (HAI) 
score by 3 points or more and no worsening of the Ishak fibrosis score.  Histological 
responses will be assessed after 48 and 192 weeks of therapy.  
 
f) Complete histological response: improvement in liver histology as defined by a 
decrease in the inflammatory component of the histological activity index (HAI) 
score by 3 points or more and no worsening of the Ishak fibrosis score and a decrease 
of the HAI score to 3 or less.  Histological responses will be assessed after 48 an 192 
weeks of therapy.  
 
g) Combined response: the combination of a virological, serological, biochemical and 
histological response.   
 
h) Complete Response:  Loss of HBsAg.  A complete response is the major focus and 
most hoped for outcome of long-term antiviral treatment of hepatitis B. A complete 
response is reason for stopping all antiviral treatment. 
 
Beneficial responses are also characterized as initial, maintained or sustained:  
 
a) Initial response: full virological or biochemical response occurring within the first 24 
weeks of therapy. 
  


 
19 
b) Maintained response: virological, serological, biochemical, histological, or 
combined response present at the time of last observation in a patient still receiving 
therapy.   
 
c) Sustained response: virological, serological, biochemical, histological or combined 
response present at the time of last observation and at least six months after stopping 
therapy.   
 
 
The primary study endpoints will be a maintained full virological response after 48 weeks 
and 192 weeks of therapy (the two points of formal statistical analysis). The major 
secondary endpoint will be absence of a failure of therapy and absence of resistance 
mutations. Other endpoints to therapy will be loss of HBeAg, loss of HBsAg, 
normalization of serum ALT, improvements in histology activity index, improvements in 
hepatic fibrosis, improvement in Fibroscan scores and decrease in HVPG. Other 
endpoints will be improvement in symptom scores at 48 and 192 weeks. 
 
Failure of therapy may be due to primary non-response, lack of virological response, 
breakthrough, or relapse, as defined below.   
 
A primary non-response is defined as lack of decrease in HBV DNA levels by at least 1 
log10 after at least 24 weeks of therapy in the absence of non-compliance.   
 
A failure in virological response is defined as failure to suppress HBV DNA below 104 
IU/ml after 48 weeks of therapy in the absence of non-compliance. 
  
A breakthrough is defined as a ≥1 log10 IU/L increase in HBV DNA level from nadir in 
two consecutive samples at least one month apart in a patient with an initial full 
virological response in the absence of non-compliance. 
 
A relapse is defined as a rise in HBV DNA levels to above 104 IU/ml or of ALT to above 
the normal range after therapy is stopped in a patient who previously had a maintained 
full virological response.   
 
These definitions are all interlocking but help to define response and non-response rates 
and whether therapy has a sustained effect. 
 
Stopping therapy: Therapy will be continued indefinitely or until one of the following 
endpoints are reached: 
 
1.   Failure of therapy: If HBV DNA levels remain consistently >104 IU/ml after one 
year of continuous therapy, patients will be offered alternative therapy or the option to 
stop therapy. Alternative therapies may include switching to combination therapy if they 
were receiving monotherapy or switching to entecavir if receiving combination therapy. 
Patients who fail to respond may also elect to receive a course of peginterferon. These 
options are available at the NIH Clinical Center on an open-label basis. 


 
20 
 
ii) Toxicity.  Either intolerance to tenofovir or the combination of tenofovir and 
emtricitabine or development of worsening renal function would be a reason to stop 
therapy (see below The risks and hazards of tenofovir and emtricitabine combination 
therapy for management of tenofovir toxicity.) 
  In either situation, entecavir or peginterferon would be options for alternative therapy.  
Discontinuation of therapy due to toxicity will be considered failure of therapy and, if 
treated, not as a part of this protocol.   
 
iii) Clearance of HBsAg.  Patients who become and remain HBsAg and HBV DNA 
negative for at least six months will have therapy discontinued.  These patients will be 
monitored at 4 week intervals for the next 6 months and then every 12 weeks.  If HBsAg 
returns or if HBV DNA levels rise above 104 IU/ml, therapy will be reinstituted.  Patients 
who clear HBsAg who are anti-HBs negative will be given a course of HBV vaccine (0, 1 
and 4-6 months).   
 
 
G. Assessment of Toxicity and modification of dose of tenofovir and emtricitabine 
 
The risks and hazards of tenofovir therapy 
 
There is limited experience with the use of tenofovir in patients with chronic hepatitis B. 
More than 12,000 HIV positive patients have been treated with tenofovir alone or in 
combination with other antiretroviral drugs for periods of 28 days to 215 weeks in Phase 
I-III clinical trials and expanded access studies. A total of 1,544 patients have received 
tenofovir 300 mg once daily in Phase I-III clinical trials; over 11,000 patients have 
received tenofovir in expanded access programs. In study 903, a double-blind, active 
controlled multicenter study comparing tenofovir 300 mg daily administered in 
combination with lamivudine and efavirenz versus stavudine (d4T), lamivudine and 
efavirenz in 600 antiretroviral naïve patients, the most common adverse reactions seen 
were mild to moderate gastrointestinal events and dizziness. Mild adverse events (Grade 
1) were common with a similar incidence in both arms and included dizziness, diarrhea 
and nausea. Selected treatment emergent moderate to severe adverse events (Grades 2-4) 
reported in ³5% of the tenofovir versus non-tenofovir arms respectively, included 
headache 14% vs. 17%, pain 13% vs. 12%, fever 8% vs. 7%, abdominal pain 7% vs. 
12%, back pain 9% vs. 8%, asthenia 6% vs. 7%, diarrhea 11% vs. 13%, nausea 8% vs. 
9%, dyspepsia 4% vs. 5%, vomiting 5% vs. 9%, lipodystrophy 1% vs. 8%, arthralgias 5% 
vs. 7%, myalgias 3% vs. 5%, depression 11% vs. 10%, insomnia 5% vs. 8%, dizziness 
3% vs. 6%, peripheral neuropathy 1% vs. 5%, anxiety 6% vs. 6%, pneumonia 5% vs. 5%, 
rash 18% vs. 12%. With the exception of fasting cholesterol and fasting triglyceride 
elevations that were more common in the stavudine group (40% and 9%) compared with 
tenofovir (19% and 1%) respectively, laboratory abnormalities observed in study 903 
occurred with similar frequency in the tenofovir and non-tenofovir treatment arms. Grade 
3/4 laboratory abnormalities reported in ³1% of treated patients include creatinine kinase 
12% vs. 12%, serum amylase 9% vs. 8%, serum AST 5% vs. 7%, serum ALT 4% vs. 5%, 
hematuria (>100 RBC’s/HPF) 7% vs. 7% and neutropenia (<750/mm3) 3% vs. 1%. In 


 
21 
study 934, 511 antiretroviral naive patients received either tenofovir and emtricitabine 
administered in combination with efavirenz or zidovudine/lamivudine administered in 
combination with efavirenz. Adverse events and laboratory abnormalities observed in this 
study were generally consistent with those seen in previous studies in treatment-
experienced or treatment naïve patients. In addition to adverse events reported from 
clinical trials, the following events have been identified during post-approval use of 
tenofovir. Because they are reported from a population of unknown size, estimates of 
frequency cannot be made. These events include allergic reactions, hypophosphatemia, 
lactic acidosis, dyspnoea, abdominal pain, increased amylase, pancreatitis, increased liver 
enzymes, hepatitis, renal insufficiency, renal failure, acute renal failure, Fanconi 
syndrome, proximal tubulopathy, proteinuria, increased creatinine, acute tubular necrosis, 
nephrogenic diabetes insipidus, polyuria and nephritis.  
 
Tenofovir has a black box warning indicating that lactic acidosis and severe 
hepatomegaly with steatosis including death have been reported with the use of 
nucleoside analogues alone or in combination with other antiretrovirals. Additionally 
severe acute exacerbations of hepatitis B have been reported in patients who are 
coinfected with HBV and HIV and have discontinued tenofovir. Tenofovir is principally 
eliminated by the kidney. The dosing interval needs to be adjusted in all patients with 
creatinine clearance <50 ml/min.  
 
The majority of safety data on tenofovir has come from HIV populations on multidrug 
regimens. The few series of patients with chronic hepatitis B treated with tenofovir have 
not reported any serious side effects. The major safety concern with tenofovir is renal 
impairment. Cases of acute renal failure and Fanconi syndrome (renal tubular injury with 
severe hypophosatemia) have been reported in association with the use of tenofovir. The 
majority of these cases occurred in patients with underlying systemic or renal disease, or 
in patients taking nephrotoxic agents, however, some cases occurred in patients without 
identified risk factors. 
 
One other potential problem identified with the use of tenofovir in the HIV population is 
a decline in bone mineral density. In a 144-week study of HIV positive treatment naïve 
patients, decreases in bone mineral density (BMD) were seen at the lumbar spine and hip 
in both arms of the study (study 903 see above). At Week 144, there was a significantly 
greater mean percentage decrease from baseline in BMD at the lumbar spine in patients 
receiving tenofovir plus lamivudine plus efavirenz compared with patients receiving 
stavudine plus lamivudine plus efavirenz. Changes in BMD at the hip were similar 
between the two treatment groups. In both groups, the majority of the reduction in BMD 
occurred in the first 24–48 weeks of the study and this reduction was sustained through 
144 weeks. Twenty-eight percent of tenofovir-treated patients vs. 21% of the comparator 
patients lost at least 5% of BMD at the spine or 7% of BMD at the hip. Clinically 
relevant fractures (excluding fingers and toes) were reported in 4 patients in the tenofovir 
group and 6 patients in the comparator group. Tenofovir disoproxil fumarate was 
associated with significant increases in biochemical markers of bone metabolism (serum 
bone-specific alkaline phosphatase, serum osteocalcin, serum C-telopeptide, and urinary 
N-telopeptide), suggesting increased bone turnover. Serum parathyroid hormone levels 


 
22 
and 1,25 Vitamin D levels were also higher in patients receiving tenofovir. The effects of 
tenofovir-associated changes in BMD and biochemical markers on long-term bone health 
and future fracture risk are unknown. 
 
The risk of carcinogenesis, mutagenesis and impairment in fertility has been studied. 
Long-term oral carcinogenicity studies of tenofovir in mice and rats were carried out at 
exposures up to approximately 16 times (mice) and 5 times (rats) those observed in 
humans at the therapeutic dose for HIV infection. At the high dose in female mice, liver 
adenomas were increased at exposures 16 times that in humans. In rats, the study was 
negative for carcinogenic findings at exposures up to 5 times that observed in humans at 
the therapeutic dose.  
 
Tenofovir was mutagenic in the in vitro mouse lymphoma assay and negative in an in 
vitro bacterial mutagenicity test (Ames test). In an in vivo mouse micronucleus assay 
tenofovir was negative when administered to male mice. 
 
There were no effects on fertility, mating performance or early embryogenic development 
when tenofovir was administered to male rats at a dose equivalent to 10 times the human 
dose based on body surface area comparisons for 28 days prior to mating and to female 
rats for 15 days prior to mating through day seven of gestation. There was however an 
alteration of the estrous cycle in female rats. 
 
Reproduction studies have been performed in rats and rabbits at doses up to 14 and 19 
times the human dose based on the body surface area comparisons and revealed no 
evidence of impaired fertility or harm to the fetus due to tenofovir. There are however, no 
adequate and well-controlled studies in pregnant women.  
 
Women of child bearing potential will have a pregnancy test at each study visit. They will 
be counseled to use at least two forms of adequate birth control while receiving study 
medications. Any female patient found to be pregnant will stop antiviral therapy and be 
followed in the Liver Diseases Clinic. 
 
The risks and hazards of emtricitabine therapy 
 
More than 2000 adult patients with HIV infection have been treated with emtricitabine 
either alone or in combination with other antiretroviral agents for periods of 10 days to 
200 weeks in Phase I-III clinical trials. Assessment of adverse reactions is based on data 
from studies 301A and 303 in which 571 treatment naïve (301A) and 440 treatment 
experienced (303) patients received emtricitabine 200mg (n-580) or comparator drug 
(n=431) for 48 weeks. The most common adverse events that occurred in patients 
receiving emtricitabine with other antiretroviral agents in clinical trials were headache, 
diarrhea, nausea and rash that were generally of mild to moderate severity. 
Approximately 1% of patients discontinued participation in the clinical trials due to these 
events. All adverse events were reported with similar frequency in emtricitabine and 
control treatment groups with the exception of skin discoloration which was reported 
with higher frequency in the emtricitabine treated group. Skin discoloration manifested 


 
23 
by hyperpigmentation on the palms and /or soles were generally mild and asymptomatic. 
The mechanism and clinical significance are unknown.  
 
Selected treatment emergent adverse events (all grades regardless of causality) reported 
in ³3% of emtricitabine-treated patients in either study 301A or 303 include abdominal 
pain 8-14% vs. 11-17%, asthenia 12-16% vs. 10-17%, headache 13-22% vs. 6-25%, 
diarrhoea 23% vs. 18-32%, dyspepsia 4-8% vs. 5-12%, nausea 13-18% vs. 12-23%, 
vomiting 9% vs. 7-12%, arthralgia 3-5% vs. 4-6%, myalgia 4-6% vs. 3-4%, abnormal 
dreams 2-11% vs. <1%-19%, depressive disorders 6-9% vs. 10-13%, dizziness 4-25% vs. 
5-26%, insomnia 7-16% vs. 3-21%, nuropathy/peripheral neuritis 4% vs. 3-13%, 
paresthesias 5-6% vs. 3-13%, increased cough 14% vs. 8-11%, rhinitis 12-18% vs. 10-
12% and skin rash 17-30% vs. 14-33% compared to comparator arm respectively. 
Treatment emergent grade ¾ laboratory abnormalities reported in >1% of emtricitabine 
treated patients in either study 301A or 303 included ALT >5X ULN 2% vs. 1%, AST 
>5X ULN 3% vs. <1%, bilirubin >2.5 X ULN 1% vs. 2%, creatine kinase >4 ULN 11% 
vs. 14%, neutropenia <750 mm3 5% vs. 3%, pancreatic enzyme elevation either amylase 
or lipase 1-2% vs. <1-2%, serum glucose 3% vs. 3% and triglycerides 10% vs. 8% 
compared to comparator arm.  
 
Emtricitabine carries a black box warning advising of lactic acidosis and severe 
hepatomegaly with steatosis including death associated with its use. 
 
Emticitabine was evaluated in a randomized placebo controlled trial in 167 patients with 
chronic hepatitis B. The incidence of clinical adverse events during treatment was similar 
in the 2 groups. Severe (grade 3 or 4) adverse events were reported in 14 (8%) of 167 
emtricitabine-treated patients and 7 of 81 patients given placebo (9%), and serious 
adverse events occurred in 8% (n = 13) and 9% (n = 7), respectively. Related serious 
adverse events were rare, 4 (2%) of 167 emtricitabine and 3 (4%) of 81 placebo patients. 
During treatment, the incidence of grade 3 or 4 laboratory abnormalities was significantly 
reduced in the emtricitabine group, 31 (19%) of 167 patients vs. 33 (41%) of 81 in the 
placebo group (P<.001), which was due to the lower incidence of grade 3 or 4 
transaminase, ALT (7% emtricitabine [n = 11], 26% placebo [n = 21]) and aspartate 
aminotransferase (2% emtricitabine [n = 3], 12% placebo [n = 10]) (P≤.001). 
 
Post treatment follow-up safety data were available from 145 patients in the emtricitabine 
group (median follow-up, 110 days) and 63 patients in the placebo group. Post treatment 
exacerbation of CHB developed in 33 patients (23%) who had received emtricitabine and 
3 placebo patients (5%) (P = .001), with a median time to onset of 10 weeks following 
the end of treatment (interquartile range, 8-16 weeks). One patient randomized to 
emtricitabine with marked bridging fibrosis at entry developed severe icteric post 
treatment exacerbation of CHB and required liver transplantation. All other patients 
recovered without clinical complications (overall, 14 with and 19 without antiviral 
therapy). 
 


 
24 
Long-term carcinogenicity studies of emtricitabine in rats and mice are in progress. 
Emtricitabine was not toxic in the reverse bacterial test (Ames test), mouse lymphoma or 
mouse micronucleus assays.  
 
Emtricitabine did not affect fertility in male rats at approximately 140-fold or in male and 
female mice at approximately 60-fold higher exposures than in humans given the 
recommended 200 mg dose. Fertility was normal in the offspring of mice exposed daily 
from before birth (in utero) through sexual maturity at daily exposures of approximately 
60-fold higher exposures than in humans given the recommended 200 mg dose. 
 
The incidence of fetal variations and malformations was not increased in embroyonal 
toxicity studies performed with emtricitabine in mice at exposures approximately 60 fold 
higher and in rabbits at approximately 120 fold higher than in humans exposures given 
the recommended 200 mg dose. There are however, no adequate and well-controlled 
studies in pregnant women.  
 
The risks and hazards of tenofovir and emtricitabine combination therapy 
 
Four hundred and forty-seven HIV-1 infected patients have received combination therapy 
with Emtriva and Viread with either a non-nucleoside reverse transcriptase inhibitor or 
protease inhibitor for 48 weeks in clinical studies. In study 934, a randomized, open-
label, active controlled multicenter study comparing Emtriva and Viread administered in 
combination with efavirenz versus zidovudine/lamivudine fixed-dose combination 
administered in combination with efavirenz in 511 antiretroviral-naïve patients, adverse 
events observed were generally consistent with those seen in other studies in treatment 
experienced or treatment-naïve patients receiving Viread and/or Emtriva. Selected 
treatment emergent adverse events (Grades 2-4) reported in ≥3% in the Emtirva and 
Viread arm compared to the non- Emtirva and Viread arm include diarrhea 7% vs. 4%, 
nausea 8% vs. 6%, vomiting 1% vs. 4%, fatigue 7% vs. 6%, sinusitis 4% vs. 2%, upper 
respiratory tract infections 3% vs. 3%, nasopharyngitis 3% vs. 1%, somnolence 3% vs. 
2%, headache 5% vs. 4%, dizziness 8% vs. 7%, depression 4% vs. 7%, insomnia 4% vs. 
5%, abnormal dream 4% vs. 3%, skin rash 5% vs. 4%. Laboratory abnormalities 
observed in this study were generally consistent with those seen in other studies of 
tenofovir and/or emtricitabine. Significant laboratory abnormalities reported in ³1% of 
patients in any treatment arm (tenofovir/emtricitabine arm 25% vs. non-
tenofovir/emtricitabine arm 22%) included elevated fasting cholesterol 15% vs. 17%, 
elevated creatine kinase 7% vs. 6%, elevated amylase 7% vs. 3%, elevated AST 3% vs., 
2%, elevated ALT 2% vs. 2%, hemoglobin <8 mg/dl 0% vs., 3%, hyperglycemia 1% vs. 
1%, hematuria 2% vs. 2%, neutropenia 3% vs. 4% and elevated fasting triglycerides 4% 
vs. 2%.   
 
In addition to the events described above for Study 934, other adverse events that 
occurred in >5% of patients receiving emtricitabine with other antiretroviral agents in 
clinical trials include abdominal pain, asthenia, arthralgia, increase cough, depressive 
disorder, dyspepsia, myalgia, paresthesia, rhinitis and rash event (including rash, pruritus, 
maculopapular rash, urticaria, vesiculobullous rash, pustular rash and allergic reaction). 


 
25 
Skin discoloration has been reported with higher frequency among emtricitabine treated 
patients. Skin discoloration, manifested by hyperpigmentation on the palms and/or 
soles was generally mild and asymptomatic. The mechanism and clinical significance 
are unknown. No additional adverse events were reported in post marketing experience 
with emtricitabine. 
 
In addition to the laboratory abnormalities described above for study 934, grade 3/4 
elevations of bilirubin (>2.5 x ULN), pancreatic amylase (>2.0 x ULN), serum glucose 
(<40 or >250 mg/dL) and serum lipase (>2.0 x ULN) occurred in <1–3% of patients 
treated with emtriciatbine. 
 
In addition to the events described above for study 934, other adverse events 
that occurred in ≥5% of patients receiving tenofovir with other antiretroviral agents in 
clinical trials include arthralgia, anxiety, fever, pain, abdominal pain, back pain, 
peripheral neuritis, peripheral neuropathy, and pneumonia. 
 
In addition to the laboratory abnormalities described above for study 934, grade 3/4 
elevations of urine glucose (≥3+) occurred in 3% of patients receiving tenofovir with 
other antiretroviral agents in clinical trials the following events have been identified 
during post-approval use of tenofovir. Because they are reported from a population of 
unknown size, estimates of frequency cannot be made. These events include allergic 
reactions, hypophosphatemia, lactic acidosis, dyspnoea, abdominal pain, increased 
amylase, pancreatitis, increased liver enzymes, hepatitis, renal insufficiency, renal failure, 
acute renal failure, Fanconi syndrome, proximal tubulopathy, proteinuria, increased 
creatinine, acute tubular necrosis, nephrogenic diabetes insipidus, polyuria and nephritis.  
 
The combination of tenofovir and emtricitabine carries a black box warning as for 
tenofovir and other nucleos(t)ide analogues highlighting that lactic acidosis and severe 
hepatomegaly with steatosis, including fatal cases, have been reported with the use of 
nucleos(t)ide analogs alone or in combination with other antiretrovirals. A majority of 
these cases have been in women. Obesity and prolonged nucleoside exposure may be risk 
factors. Particular caution should be exercised when administering nucleoside analogs to 
any patient with known risk factors for liver disease; however, cases have also been 
reported in patients with no known risk factors. 
 
A major safety concern with tenofovir is renal impairment. Cases of acute renal failure 
and Fanconi syndrome (renal tubular injury with severe hypophosatemia) have been 
reported in association with the use of tenofovir. The majority of these cases occurred in 
patients with underlying systemic or renal disease, or in patients taking nephrotoxic 
agents, however, some cases occurred in patients without identified risk factors. Patients 
will be monitored by a series of tests for renal toxicity including calculated GFR using 
the Modification of Diet in Renal Disease (MDRD) formula, urine analysis and serum 
phosphate. Dose adjustments or cessation will be based upon any of the following 
criteria: 
1) Absolute decline in GFR by 25 mls/min/1.73 m2 confirmed on two occasions 2 weeks 
apart. GFR will be calculated using the Modification of Diet in Renal Disease (MDRD) 


 
26 
formula: (MDRD GFR (ml/min/1.73m2=170 x[PCr]-.999 X [Age]-0.176 X[.0762 if patient is 
female] X [1.180 if patient is black] X [SUN]-0.170 X[Alb]+.318 where PCr=serum 
creatinine concentration (mg/dl) (alkaline picrate method); SUN=serum urea nitrogen 
concentration (mg/dl) (urease method); Alb=serum albumin concentration (g/dl) 
(bromocresol green method)).  
2) Abnormality in any one of the following 4 parameters calculated GFR, urine glucose, 
serum phosphate and a routine urine analysis will trigger a formal renal evaluation. This 
will include including assessment of GFR by 24 urine hour creatinine clearance, urine 
glucose, fractional excretion of phosphate, 24 hour urine for amino acids and serum uric 
acid, If the evaluation is consistent with Fanconi’s syndrome, patients will be 
discontinued from therapy indefinitely.  
3) For Grade 1 toxicity serum creatinine ≥ .5 above baseline, the patient will be 
monitored weekly until the creatinine returns to baseline or ≤ 0.3 mg/dL of the baseline 
value. For confirmed Grade 2 and ≥ 0.5 increases from baseline, therapy will be 
permanently discontinued.  
 
In a 144-week study of HIV positive treatment naïve patients, decreases in bone mineral 
density (BMD) were seen at the lumbar spine and hip in both arms of the study (study 
903 see above). At Week 144, there was a significantly greater mean percentage decrease 
from baseline in BMD at the lumbar spine in patients receiving tenofovir plus lamivudine 
plus efavirenz compared with patients receiving stavudine plus lamivudine plus 
efavirenz. Changes in BMD at the hip were similar between the two treatment groups. In 
both groups, the majority of the reduction in BMD occurred in the first 24–48 weeks of 
the study and this reduction was sustained through 144 weeks. Twenty-eight percent of 
tenofovir-treated patients vs. 21% of the comparator patients lost at least 5% of BMD at 
the spine or 7% of BMD at the hip. Clinically relevant fractures (excluding fingers and 
toes) were reported in 4 patients in the tenofovir group and 6 patients in the comparator 
group. Tenofovir disoproxil fumarate was associated with significant increases in 
biochemical markers of bone metabolism (serum bone-specific alkaline phosphatase, 
serum osteocalcin, serum C-telopeptide, and urinary N-telopeptide), suggesting increased 
bone turnover. Serum parathyroid hormone levels and 1,25 Vitamin D levels were also 
higher in patients receiving tenofovir. The effects of tenofovir-associated changes in 
BMD and biochemical markers on long-term bone health and future fracture risk are 
unknown. 
 
The risk of carcinogenesis, mutagenesis and impairment in fertility has been studied. 
Long-term oral carcinogenicity studies of tenofovir in mice and rats were carried out at 
exposures up to approximately 16 times (mice) and 5 times (rats) those observed in 
humans at the therapeutic dose for HIV infection. At the high dose in female mice, liver 
adenomas were increased at exposures 16 times that in humans. In rats, the study was 
negative for carcinogenic findings at exposures up to 5 times that observed in humans at 
the therapeutic dose.  
 
Tenofovir was mutagenic in the in vitro mouse lymphoma assay and negative in an in 
vitro bacterial mutagenicity test (Ames test). In an in vivo mouse micronucleus assay 
tenofovir was negative when administered to male mice. 


 
27 
 
There were no effects on fertility, mating performance or early embryogenic development 
when tenofovir was administered to male rats at a dose equivalent to 10 times the human 
dose based on body surface area comparisons for 28 days prior to mating and to female 
rats for 15 days prior to mating through day seven of gestation. There was however an 
alteration of the estrous cycle in female rats. 
 
The incidence of fetal variations and malformations was not increased in embryofetal 
toxicity studies performed with emtricitabine in mice at exposures (AUC) approximately 
60-fold higher than human exposures at the recommended daily dose. 
 
Reproduction studies have been performed in rats and rabbits at doses up to 14 and 19 
times the human dose based on the body surface area comparisons and revealed no 
evidence of impaired fertility or harm to the fetus due to tenofovir. There are however, no 
adequate and well-controlled studies in pregnant women. 
 
 
 
H. Viral resistance 
 
Tenofovir resistance is defined phenotypically as: (1) rise in serum HBV-DNA levels to 
levels above 104 IU per ml (by quantitative PCR) after they had fallen below this level 
during therapy in patients who have been compliant with their regimen and genotypically 
as (2) documented mutation/s in the reverse transcriptase region of the HBV polymerase 
gene (thus far the only documented mutation is rtA194T), and biochemically as (3) rise in 
serum aminotransferases to twice the upper limit of normal range. Patients who develop 
resistance will be continued on the therapy if they agree to stay on therapy and if serum 
aminotransferases and HBV-DNA are consistently lower than pretreatment levels or 
changed to other available agents if clinically indicated. 
 
Emtricitabine resistance in this study can only be defined phenotypically as a rise in 
serum aminotransferases to twice the upper limit of normal range. Genotypic resistance is 
defined by the typical mutations in the conserved catalytic region of the HBV polymerase 
gene (YMDD region). 
 
Monitoring for mutations in the reverse transcriptase domain of the HBV-DNA 
polymerase on combination therapy will be performed on serum samples obtained at 
baseline, and yearly on all serum samples that have detectable HBV DNA from patients 
receiving tenofovir plus emtricitabine and tenofovir monotherapy. The monitoring will be 
done by sequence analysis of the reverse transcriptase region of the HBV DNA 
polymerase gene and will be performed by LDB, NIDDK. Novel mutations will be 
correlated with the clinical response. Antiviral susceptibility and cross resistance testing 
using in vitro assays will be conducted by Gilead Sciences using stored serum samples. 
Resistance data will be submitted to the FDA according to the FDA guidance document 
entitled, “Guidance for submitting HBV Resistance Data.” 
 


 
28 
I. Statistical analysis 
Superiority of combination therapy compared to monotherapy with tenofovir will be 
tested. The primary analysis will be conducted at 1 and 4 years on the entire study cohort 
(Groups A-D). A separate analysis will be conducted on previously treated subjects with 
resistance combining all HBeAg-positive and -negative cases. We predict the rate of full 
virological response to combination therapy will be 94% and to tenofovir monotherapy to 
be 70% at 4 years. A Fisher’s exact test with a .05 two-sided significance level will have 
86% power to detect the difference between a combination therapy proportion of p1 of 
.94 and a monotherapy proportion of p2 .70 if the sample size in each group is 50. 
Secondary analyses will be done within the HBeAg positive and negative stratum and the 
nucleos(t)ide naïve and nucleos(t)ide treated stratum. Variables to be analyzed in 
association with a virological response will include: baseline ALT and HBV DNA level, 
liver histology, HBV genotype and previous resistance. Patients with missing data or who 
drop out of the study will be considered as treatment failures on an intention to treat 
basis. For comparison of means, Student’s t-test will be used. All reported p-values will 
be 2-sided.  
J.   Hazards and Discomforts 
1. The risks and discomforts of frequent phlebotomy. To document stable levels of 
biochemical and serologic markers of chronic hepatitis and to monitor the effects and 
toxicities of the combination of tenofovir and FTC, frequent blood sampling will be 
required. Patients will have between 11 and 12 venipunctures during the first 48 
weeks of the study and 4 to 6 each year thereafter. Each venipuncture will be for 
approximately 20 to 75 cc of blood. The total amount of blood drawn during an 8 
week period will not exceed 10.5 ml/Kg or 550 mls, whichever is smaller. 
 
2. The risks and discomforts of HIV testing. Patients will have blood tested for 
anti-HIV at entry.  Mention of anti-HIV is made in the consent form which includes 
the exact language used in the standard consent form used for anti-HIV testing at the 
Clinical Center. It is important to test for HIV infection as both tenofovir and 
emtricitabine have activity against HIV and a treatment regimen using only two drugs 
against HIV would not be considered standard of care. 
 
3. The risks and discomfort of percutaneous liver biopsy. Patients will undergo up to 
three liver biopsies in this protocol namely: one before therapy, a second at 48 weeks, 
and a third at 192 weeks. Patients will not have to undergo the initial liver biopsy if 
they had a biopsy within the previous 2 years that is adequate and available for 
analysis. In addition, patients with inadequate platelet counts (<70,000/mm3) or 
coagulation parameters (prothrombin time > 15 seconds, INR>1.7) will not undergo 
liver biopsy as a part of this protocol. Patients requiring liver biopsy will be admitted 
to the Clinical Center for two days for this procedure and other blood testing. The 
major side effects of liver biopsy are pain, bacteremia, puncture of another organ and 
bleeding. Local pain and discomfort at the liver biopsy site occurs in about 20% of 
persons undergoing percutaneous liver biopsy. This is transient (lasting one to twelve 
hours) and is usually mild, rarely requiring analgesics.  Bacteremia occurs in 1-2% of 
persons undergoing liver biopsy.  In the absence of bile duct obstruction, this is 


 
29 
almost always self-limited and is rarely symptomatic.  Significant bleeding after liver 
biopsy is the most serious side effect of this procedure.  In the absence of a blood 
coagulation defect or hepatic malignancy, significant bleeding is rare, occurring in 
less than one in a thousand cases of liver biopsy.  Death due to bleeding after liver 
biopsy has been reported in less than 1/10,000 cases.  At the NIH Clinical Center, the 
Liver Diseases Branch has performed approximately 150 liver biopsies each year for 
the last 20 years. During this time, only two patients died as a complication of biopsy.  
One of these patients had cirrhosis and advanced hepatocellular carcinoma and the 
second had severe coagulation disorders. Both bled from the liver biopsy site and died 
after surgical attempts to stop the bleeding were unsuccessful. 
 
4. The risks and hazards of tenofovir therapy. See section G. 
 
5. The risks and hazards of tenofovir and emtricitabine combination therapy. See 
section G. 
 
L. Data and Safety Monitoring 
 
The adequacy of data acquisition and storage and the monitoring of safety in this 
trial will be done by the principal investigator in collaboration with the associate 
investigators. Data and safety are reviewed weekly in clinical research rounds by the 
Liver Diseases Branch, NIDDK.  These rounds are separate from regular clinical 
rounds and consist of review of all study patients including flow sheets of major 
safety and efficacy measurements without knowledge of which therapy is used.  
Monitoring of this study will also be conducted by the statistical department of 
NIDDK who will have knowledge of the patient allocation. Reports of serious 
adverse events are made to the Clinical Director NIDDK, the IRB, study monitor and 
the FDA.   
 
M. Adverse Event Reporting 
 
 
Adverse events, protocol deviations, unanticipated problems (UP), Unanticipated 
Adverse Device Effects (UADEs), serious adverse events, sponsor and serious, are 
defined as described in NIH HRPP SOP 16 (“Reporting Requirements for Unanticipated 
Problems, Adverse Events and Protocol Deviations.”).  All adverse events at least 
possibly related to the patient’s participation in the research protocol, including those 
observed by or reported to the research team, will be recorded.  Serious unanticipated 
problems and serious protocol deviations will be reported to the IRB and CD as soon as 
possible but not more than 7 days after the PI first learns of the event.  Not serious 
unanticipated problems will be reported to the IRB and CD as soon as possible but not 
more than 14 days after the PI first learns of the event. 
 
Non-serious protocol deviations will only be reported to the IRB (within 14 days 
after the PI first learns of the event) if they represent a departure from NIH policies for 
the conduct of human subjects research, adversely affect the health care of the subject(s) 
or compromise the interpretation or integrity of the research.  Non-serious protocol 


 
30 
deviations that result from normal subject scheduling variations or technical issues 
associated with sampling that does not impact the health of the subject or the 
interpretation of the study data will not be reported. 
 
All serious adverse events that are assessed as possibly, probably or definitely 
related to tenofovir or tenofovir plus emtricitabine will be reported to the FDA and 
Gilead within 15 days by submission of a serious adverse event form and a written report 
for events occurring within this protocol. Adverse events that are expected as a part of 
treatment or procedures outlined in the protocol will not be reported unless they occur at 
a rate or severity greater than known to occur in patients undergoing the treatment or 
procedures. If AEs associated with the treatment and procedures in the study occur at a 
rate or severity greater than known to occur, they will be reclassified as a UP and 
reported as such. AEs with known relation to the natural history of chronic hepatitis B or 
to other pre-existing conditions will not be reported unless they occur at a rate or severity 
greater than known to occur in patients with hepatitis B or the subject’s other pre-existing 
conditions. AEs that are unrelated to the research will not be reported. The PI is 
responsible for summarizing all reportable serious adverse events and adverse events at 
the time of Continuing Review. Deaths and life-threatening events will be reported to the 
Clinical Director and IRB within 7 days after the PI first learns of the event. Any 
pregnancies that occur during the study and of the outcome of those pregnancies with 
relevant information will be reported to Gilead on a timely basis. 
 
Any information in the literature, or that has evolved from similar research, and 
that might affect the IRB’s analysis of risk/benefit for the protocol will be reported to the 
IRB at the time of Continuing Review.  If such information is obtained before the time of 
continuing review, it should be reported to the IRB at the time that it becomes known, 
and summarized at the time of continuing review. 
Study procedures will be subject to audits and/or monitoring visits to ensure 
compliance with the protocol and applicable regulatory requirements consistent with the 
NIDDK quality assurance program plan.  Audit and/or monitoring visit results will be 
reported to the Principal Investigator for further reporting as appropriate.  Study 
documents and pertinent hospital or clinical records will be reviewed to verify that the 
conduct of the study is consistent with the protocol plan. 
 
 
 
N. Enrollment of Children, Women and Minority Individuals 
 


 
31 
The current protocol excludes children (age limit > 18 years) as tenofovir has not 
been used in children for the treatment of chronic hepatitis B. Currently lamivudine is 
approved for use in children.  Chronic hepatitis B is rare in children in the U.S. and 
the implications of long-term therapy are great.   
Chronic hepatitis B is much more common among men than women.  We expect to 
include women in the proportions that occur in this disease.  Thus, we expect 10-20% 
of patients to be women.  The exclusion of women interested in getting pregnant or 
who are not able to practice adequate birth control would be the only possible bias 
introduced in attaining adequate representation of women in this study.    
 
The distribution of minority individuals in recent studies of nucleoside therapy of 
hepatitis B at the NIH Clinical Center has been reported yearly to the NIDDK IRB. In 
our study of adefovir and lamivudine (01-DK-0246), 62% of 39 enrolled patients 
were minority individuals, including 46% Asian-Americans, 13% African-Americans 
and 3% Hispanic Whites.   Chronic hepatitis B is far more common among Asian 
Americans (2 to 10% of adults) than African Americans (1-2%) and Caucasians 
(~0.5%) and we expect that at least one-third of patients enrolled in this study will be 
Asian-Americans.  There is no reason to suspect that response rates are different in 
different racial or ethnic groups.   
O. Research Use, Storage and Disposition of Human Samples and Data:   
 
Patients will have serum stored from selected time points during this study.  These 
specimens will be used for repeat virological testing and special tests as needed (such as 
for viral levels, HBV genotype or serotype, HBV DNA sequence or testing for serum 
levels of cytokines or interferon induced genes).  Samples may be used to assess factors 
associated with response or non-response to antiviral therapy.  Liver biopsy tissue may be 
stored if a biopsy is done before therapy and if residual tissue is available after routine 
samples are taken for routine histological staining and evaluation.  These samples will be 
tested in the Liver Diseases Branch or the routine clinical and surgical pathology services 
of the Clinical Center. Stored serum will be used to perform in vitro antiviral 
susceptibility and cross resistance testing. Gilead Sciences will conduct these assays and 
serum samples will not contain any patient identifiers. Samples will be sent as soon as 
virologic breakthrough is identified and Gilead will have one year after receipt of the 
sample in which to provide LDB, NIDDK with the results. Research records and data as 
well as liver biopsy slides, biopsy reports, liver tissue and sera with the patient’s name 
and a unique identifier will be stored indefinitely in our locked offices and freezers, the 
medical record department and the pathology department.  These materials will be 
protected and tracked by standard operating procedures in the medical record and 
pathology departments as well as a compulsive filing system in our locked offices and 
freezers.  There will be redundant storage of clinical information in the medical record 
department and our offices. Likewise, there will be redundant storage of biopsy 
information and materials in the pathology department and our offices.  This should 
minimize the risk of loss or destruction of information and specimens. If that were to 
occur we would report it to the IRB.  We do not plan to destroy this personal medical 
information or the liver biopsy specimens or research subject sera after completion of the 


 
32 
study because it may be critically important for physicians (here or elsewhere) to have 
access them when caring for these patients in the future.  
 
P. Consent process 
 
Written informed consent will be obtained from the participant prior to any screening 
visits, study procedures or treatments. The Principal Investigator or other designated 
qualified protocol investigators (listed on the protocol’s face page) will explain the study 
in language understandable to the subject. Potential study subjects will be informed of 
study rationale, design, participation burden, risks, benefits and side effects of therapy 
during routine LDB clinic visits and will have an opportunity to ask questions about the 
proposed study. They will be provided a copy of the study consent form to take home and 
review in more detail. Sufficient time and opportunity will be given for discussion of the 
research as well as to answer any questions they may have, taking care to minimize or 
eliminate the perception of coercion or undue influence. The participant and the 
investigator will sign the current IRB-approved informed consent document. A witness 
will also sign the consent document to attest only to the validity of the signature of the 
subject, not the validity or quality of the consent. A copy of the consent will be given to 
the subject for future reference. The signed documents will be sent to the Medical 
Records Department for placement in the subject's permanent CC medical record. The 
consent process will additionally be documented in the medical record. 
 
If a subject indicates a desire to participate in the research study, he/she will have all 
screening laboratories, radiologic imaging and if necessary, liver biopsy, performed 
through our natural history protocol 91-DK-0214. Hepatitis B can be a very dynamic 
disease and liver pathology can change rapidly as opposed to the scenario with hepatitis 
C. In contrast to other chronic liver diseases a liver biopsy is very helpful and in some 
cases essential to manage patients with chronic hepatitis B. How often one should 
perform a follow-up biopsy is open to debate and is influenced by many factors. For 
clinical investigation the ideal duration to perform a baseline liver biopsy would be 
within one year prior to enrollment, however a period of 2 years seems a reasonable 
compromise without being arbitrary. In our experience 2 years provides enough time for 
clinically significant changes to be observed without subjecting patients to unnecessary 
risk. We believe that it is medically indicated for every patient with chronic hepatitis B to 
undergo a liver biopsy before embarking on therapy that may last more than a decade. 
Potential study subjects who meet study inclusion and exclusion criteria will sign the 
consent form on day 0 of therapy, prior to randomization. 
 
 
P.2 Short Form Consent  
We do not plan to enroll non-English speaking subjects; however they are not excluded 
from participation either.  Should a non-English speaking subject be enrolled, IRB 
approval will be obtained to use the short form process in the absence of a fully translated 
consent document.  Requests for IRB approval will be obtained prior to implementing the 
short form consent process.  The short form consent process will be incompliance with 
SOP 12.9.1 of 45 CFR 46.117(b)(2). 


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HBeAg-negative chronic hepatitis B. N Engl J Med 2006;354:1011-20. 
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34 
18. 
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statement on the management of chronic hepatitis B: an update. J Gastroenterol Hepatol 
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Liaw YF, Leung N, Guan R, et al. Asian-Pacific consensus statement on the 
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Consensus statements on the prevention and management of hepatitis B and 
hepatitis C in the Asia-Pacific region. Core Working Party for Asia-Pacific Consensus on 
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Keeffe EB, Dieterich DT, Han SH, et al. A treatment algorithm for the 
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22. 
de Franchis R, Hadengue A, Lau G, et al. EASL International Consensus 
Conference on Hepatitis B. 13-14 September, 2002 Geneva, Switzerland. Consensus 
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Lok AS, Heathcote EJ, Hoofnagle JH. Management of hepatitis B: 2000--
summary of a workshop. Gastroenterology 2001;120:1828-53. 
24. 
Liaw YF, Leung NW, Chang TT, et al. Effects of extended lamivudine therapy in 
Asian patients with chronic hepatitis B. Asia Hepatitis Lamivudine Study Group. 
Gastroenterology 2000;119:172-80. 
25. 
Lau DT, Khokhar MF, Doo E, et al. Long-term therapy of chronic hepatitis B 
with lamivudine. Hepatology 2000;32:828-34. 
26. 
Hadziyannis SJ, Papatheodoridis GV, Dimou E, Laras A, Papaioannou C. 
Efficacy of long-term lamivudine monotherapy in patients with hepatitis B e antigen-
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27. 
Hadziyannis SJ, Tassopoulos NC, Heathcote EJ, et al. Long-term therapy with 
adefovir dipivoxil for HBeAg-negative chronic hepatitis B. N Engl J Med 
2005;352:2673-81. 
28. 
Chang TT, Chao Y-T, Kaymakoglu S, Cheinquer H, Pessoa M et al. Entecavir 
Maintained Virological Suppression Through 3 Years Of Treatment In Antiviral Naive 
HBeAg (+) Patients (ETV 022/901). Hepatology 2006;44:229A. 
29. 
Locarnini S. Molecular virology and the development of resistant mutants: 
implications for therapy. Semin Liver Dis 2005;25 Suppl 1:9-19. 
30. 
Tenney DJ, Levine SM, Rose RE, et al. Clinical emergence of entecavir-resistant 
hepatitis B virus requires additional substitutions in virus already resistant to Lamivudine. 
Antimicrob Agents Chemother 2004;48:3498-507. 
31. 
Colonno R, Rose RE, Pokornowski K, Baldick CJ, Klesczewski K et al. 
Assessment At Three Years Shows High Barrier To Resistance Is Maintained In 
Entecavir Treated Nucleoside Naive Patients While Resistance Emergence Increases 
Over Time In Lamivudine Refractory Patients Hepatology 2006;44:229A. 
32. 
Honkoop P, de Man RA, Niesters HG, Zondervan PE, Schalm SW. Acute 
exacerbation of chronic hepatitis B virus infection after withdrawal of lamivudine 
therapy. Hepatology 2000;32:635-9. 
33. 
Boni C, Bertoletti A, Penna A, et al. Lamivudine treatment can restore T cell 
responsiveness in chronic hepatitis B. J Clin Invest 1998;102:968-75. 


 
35 
34. 
Boni C, Penna A, Ogg GS, et al. Lamivudine treatment can overcome cytotoxic 
T-cell hyporesponsiveness in chronic hepatitis B: new perspectives for immune therapy. 
Hepatology 2001;33:963-71. 
35. 
Mizukoshi E, Sidney J, Livingston B, et al. Cellular immune responses to the 
hepatitis B virus polymerase. J Immunol 2004;173:5863-71. 
36. 
Boni C, Penna A, Bertoletti A, et al. Transient restoration of anti-viral T cell 
responses induced by lamivudine therapy in chronic hepatitis B. J Hepatol 2003;39:595-
605. 
37. 
Janssen HL, van Zonneveld M, Senturk H, et al. Pegylated interferon alfa-2b 
alone or in combination with lamivudine for HBeAg-positive chronic hepatitis B: a 
randomised trial. Lancet 2005;365:123-9. 
38. 
Peters MG, Hann Hw H, Martin P, et al. Adefovir dipivoxil alone or in 
combination with lamivudine in patients with lamivudine-resistant chronic hepatitis B. 
Gastroenterology 2004;126:91-101. 
39. 
Lai CL, Lim SG, Brown NA, et al. A dose-finding study of once-daily oral 
telbivudine in HBeAg-positive patients with chronic hepatitis B virus infection. 
Hepatology 2004;40:719-26. 
40. 
Lai CL, Leung N, Teo EK, et al. A 1-year trial of telbivudine, lamivudine, and the 
combination in patients with hepatitis B e antigen-positive chronic hepatitis B. 
Gastroenterology 2005;129:528-36. 
41. 
Hadziyannis SJ, Tassopoulos NC, Heathcote EJ, et al. Long-term therapy with 
adefovir dipivoxil for HBeAg-negative chronic hepatitis B for up to 5 years. 
Gastroenterology 2006;131:1743-51. 
42. 
van Bommel F, Wunsche T, Mauss S, et al. Comparison of adefovir and tenofovir 
in the treatment of lamivudine-resistant hepatitis B virus infection. Hepatology 
2004;40:1421-5. 
43. 
van Bommel F, Zollner B, Sarrazin C, et al. Tenofovir for patients with 
lamivudine-resistant hepatitis B virus (HBV) infection and high HBV DNA level during 
adefovir therapy. Hepatology 2006;44:318-25. 
44. 
Ristig MB, Crippin J, Aberg JA, et al. Tenofovir disoproxil fumarate therapy for 
chronic hepatitis B in human immunodeficiency virus/hepatitis B virus-coinfected 
individuals for whom interferon-alpha and lamivudine therapy have failed. J Infect Dis 
2002;186:1844-7. 
45. 
Neff GW, Nery J, Lau DT, et al. Tenofovir therapy for lamivudine resistance 
following liver transplantation. Ann Pharmacother 2004;38:1999-2004. 
46. 
Marcellin P, Gane E, Buti M, et al. Regression of cirrhosis during treatment with 
tenofovir disoproxil fumarate for chronic hepatitis B: a 5-year open-label follow-up 
study. Lancet 2013;381:468-75. 
47. 
Gish RG, Trinh H, Leung N, et al. Safety and antiviral activity of emtricitabine 
(FTC) for the treatment of chronic hepatitis B infection: a two-year study. J Hepatol 
2005;43:60-6. 
48. 
Lim SG, Ng TM, Kung N, et al. A double-blind placebo-controlled study of 
emtricitabine in chronic hepatitis B. Arch Intern Med 2006;166:49-56. 
49. 
Dando TM, Wagstaff AJ. Emtricitabine/tenofovir disoproxil fumarate. Drugs 
2004;64:2075-82; discussion 83-4. 


 
36 
50. 
Borroto-Esoda K, Vela JE, Myrick F, Ray AS, Miller MD. In vitro evaluation of 
the anti-HIV activity and metabolic interactions of tenofovir and emtricitabine. Antivir 
Ther 2006;11:377-84. 
 
 


APPENDIX A. Flow sheet for follow-up clinic visits, medication schedule, and 
diagnostic tests for patients on combination therapy with tenofovir and emtricitabine.  
 
 
 
Week of therapy 
Time 
Pre-
1* 
Pre-
2* 
0 
2 
4 
8 
12 24 36 48 q 
12  
192 
Clinic visit 
X 
X 
X X X X X 
X 
X 
X 
X 
X 
Admission 
 
X 
 
 
 
 
 
 
 
X 
 
X 
Routine bloods† 
X 
X 
X X X X X 
X 
X 
X 
X 
X 
Urine† 
 
 
X X X X X 
X 
X 
X 
X 
X 
Extended tests¶ 
 
X 
X  
 
 
X 
X 
X 
X 
X 
X 
Creatinine Clearance 
 
X 
 
 
 
 
 
 
 
X 
 
X 
Ultrasound‡ 
 
X 
 
 
 
 
 
 
 
X 
 
X 
Liver biopsy 
 
X 
 
 
 
 
 
 
 
X 
 
X 
Alpha fetoprotein‡ 
 
X 
 
 
 
 
 
 
 
X 
 
X 
Immunologic tests 
 
X 
 
X X  
X 
 
 
X 
 
 
Fibroscan‡ 
 
X 
 
 
 
 
 
 
 
X 
 
X 
Bone mineral density 
 
X 
 
 
 
 
 
 
 
X 
 
X 
FTCvsPlacebo/Tenofovir  
X 
X X X X X 
X 
X 
X 
X 
X 
* Pre is the initial evaluation which will be an outpatient clinic visit for those who do not 
require a pretreatment biopsy and a clinical center admission for those who require a 
pretreatment liver biopsy. 
† Routine bloods include CBC, chemistry-20 panel, serum lactic acid and HBV DNA by 
quantitative PCR. 
† Urine tests include standard urine analysis and spot urine protein/creatinine ratio and a 
pregnancy test for women of child bearing potential. 
¶ Extended tests include: INR, alphafetoprotein, HBsAg, anti-HBs, HBeAg and anti-HBe 
and are measured every 12 weeks. 
‡ Ultrasound and fibroscan will be measured every 48 weeks. 
 


 
38 
Appendix B.  
Table 1 Common Toxicity Criteria 
 
Grade 
Adverse 
event 
0 
1 
2 
3 
4 
Nausea 
None 
Able to eat 
Oral intake 
significantly 
decreased 
No 
significant 
intake, 
requiring IV 
fluids 
- 
Diarrhea 
patients 
without 
colostomy: 
none 
increase of 
<4 
stools/day 
over pre-
treatment 
increase of 
4-6 
stools/day, 
or nocturnal 
stools 
increase of 
7 
stools/day or 
incontinence
; or need for 
parenteral 
support for 
dehydration 
Physiologic 
consequence
s requiring 
intensive 
care; or 
hemodynami
c collapse 
Fatigue 
(lethargy, 
malaise, 
asthenia) 
None 
increased 
fatigue over 
baseline, but 
not altering 
normal 
activities 
moderate 
(e.g., 
decrease in 
performance 
status by 1 
ECOG level 
or 20% 
Karnofsky 
or Lansky) 
or causing 
difficulty 
performing 
some 
activities 
severe (e.g., 
decrease in 
performance 
status by2 
ECOG 
levels or 
40% 
Karnofsky 
or Lansky) 
or loss of 
ability to 
perform 
some 
activities 
bedridden or 
disabling 
Myalgia 
(muscle 
pain) 
 
 
 
 
none 
mild pain 
not 
interfering 
with 
function 
moderate 
pain: pain or 
analgesics 
interfering 
with 
function, but 
not 
interfering 
with 
activities of 
daily living 
severe pain: 
pain or 
analgesics 
severely 
interfering 
with 
activities of 
daily living 
disabling 
Confusion 
normal 
Confusion 
or 
Confusion 
or 
Confusion 
or delerium 
Harmful to 
others or 


 
39 
disorientatio
n or 
attention 
deficit of 
brief 
duration; 
resolves 
spontaneousl
y with no 
sequelae 
disorientatio
n or 
attention 
deficit 
interfering 
with 
function but 
not 
interfering 
with 
activities of 
daily living 
interfering 
with 
activities of 
daily living 
self; 
requiring 
hospitalizati
on 
Mood 
alteration-
anxiety, 
agitation 
 
normal 
mild mood 
alteration 
not 
interfering 
with 
function 
 
moderate 
mood 
alteration 
interfering 
with 
function, but 
not 
interfering 
with 
activities of 
daily living 
severe mood 
alteration 
interfering 
with 
activities of 
daily living 
 
suicidal 
ideation or 
danger to 
self 
Mood 
alteration- 
 
normal 
depression 
mild mood 
alteration 
not 
interfering 
with 
function 
moderate 
mood 
alteration 
interfering 
with 
function, but 
not 
interfering 
with 
activities of 
daily living 
severe mood 
alteration 
interfering 
with 
activities of 
daily living 
 
suicidal 
ideation or 
danger to 
self 
Mood 
alteration-
euphoria 
 
normal 
mild mood 
alteration 
not 
interfering 
with 
function 
moderate 
mood 
alteration 
interfering 
with 
function, but 
not 
interfering 
with 
activities of 
daily living 
severe mood 
alteration 
interfering 
with 
activities of 
daily living 
 
danger to 
self 
Vision-
normal 
- 
symptomatic symptomatic 
- 


 
40 
blurred 
vision 
and 
interfering 
with 
function, but 
not 
interfering 
with 
activities of 
daily living 
and 
interfering 
with 
activities of 
daily living 
Vision-
double 
vision 
(diplopia) 
normal 
- 
symptomatic 
and 
interfering 
with 
function, but 
not 
interfering 
with 
activities of 
daily living 
symptomatic 
and 
interfering 
with 
activities of 
daily living 
- 
Inner 
ear/hearing 
normal 
hearing loss 
on 
audiometry 
only 
tinnitus or 
hearing loss, 
not requiring 
hearing aid 
or treatment 
tinnitus or 
hearing loss, 
correctable 
with hearing 
aid or 
treatment 
severe 
unilateral or 
bilateral 
hearing loss 
(deafness), 
not 
correctable 
Fever (in the 
absence of 
neutropenia, 
where 
neutropenia 
is defined as 
AGC <1.0 x 
10 9 /L) 
none 
38.0 - 
39.0°C 
(100.4-
102.2°F) 
39.1 - 
40.0°C 
(102.3 -
104.0°F) 
>40.0°C 
(>104.0°F ) 
for<24hrs 
>40.0°C 
(>104.0°F ) 
for>24hrs 
Leukocytes 
(total WBC) 
WNL 
<LLN - 3.0 
x 109 
/L<LLN  
3000/mm3 
2.0 - <3.0 
x 109 
/L2000 - 
<3000/mm3 
1.0 - <2.0 
x 109 
/L1000 - 
<2000/mm3 
<1.0 x 109 
/L<1000/m
m3 
Neutrophils/ 
granulocytes 
(ANC/AGC) 
WNL 
1.5 - <2.0 
x 109 
/L1500 - 
<2000/mm3 
1.0 - <1.5 
x 109 
/L1000 - 
<1500/mm3 
0.5 - <1.0 
x 109 
/L500 - 
<1000/mm3 
<0.5 x 109 
/L<500/mm3 
Hemoglobin  (Hgb) WNL 
<LLN - 10.0 
g/dL 
8.0 - <10.0 
g/dL 
6.5 - <8.0 
g/dL 
<6.5 g/dL 
Platelets 
WNL 
<LLN - 75.0 
50.0 - 
10.0 - 
<10.0 x 109 


 
41 
x 109 
/L<LLN - 
75,000/mm3 
<75.0 x 109 
/L50,000 - 
<75,000/mm
3 
<50.0 x 109 
/L10,000 - 
<50,000/mm
3 
/L<10,000/
mm3 
Alkaline 
phosphatase 
WNL 
>ULN – 
2.5X ULN 
>2.5 – 5.0 X 
ULN 
>5.0 – 20.0 
x ULN 
>20.0 X 
ULN 
SGPT 
(ALT) 
(serum 
glutamic 
pyruvic 
transaminase
) 
WNL 
>ULN – 
2.5X ULN 
>2.5 – 5.0 X 
ULN 
>5.0 – 20.0 
x ULN 
>20.0 X 
ULN 
SGOT 
(AST) 
(serum 
glutamic 
oxaloacetic 
transaminase
) 
WNL 
>ULN – 
2.5X ULN 
>2.5 – 5.0 X 
ULN 
>5.0 – 20.0 
x ULN 
>20.0 X 
ULN 
Bilirubin 
WNL 
>ULN – 1.5 
X ULN 
>1.5 – 3.0 x 
ULN 
>3.0 – 10.0 
x ULN 
>10 x ULN 
Hypoalbumi
nemia 
WNL 
<LLN – 3 
g/dL 
≥2 - <3 g/dL 
<2 g/dL 
- 
Prothrombin 
time (PT) 
WNL 
>ULN - 
1.5 x ULN 
>1.5 - 2 x 
ULN 
>2 x ULN 
 
Liver 
dysfunction/ 
failure 
(clinical) 
normal 
- 
- 
asterixis 
Encepalopat
hy or coma 
Hypokalemi
a 
WNL 
<LLN - 3.0 
mmol/L 
- 
2.5 - <3.0 
mmol/L 
<2.5 
mmol/L 
Hypophosph
atemia 
WNL 
<LLN -2.5 
mg/dL 
<LLN - 0.8 
mmol/L 
2.0 - <2.5 
mg/dL0.
6 - <0.8 
mmol/L 
1.0 - <2.0 
mg/dL0.
3 - <0.6 
mmol/L 
<1.0 mg/dL 
<0.3 
mmol/L 
Creatinine 
WNL 
>.5 above 
baseline 
>1.5 – 3.0 x 
ULN 
>3.0 – 6.0 x 
ULN 
>6.0 x ULN 
Bicarbonate 
WNL 
<LLN – 16 
mEq/dL 
11 – 15 
mEq/dL 
8 – 10 
mEq/dL 
<8 mEq/dL 
CPK 
(creatine 
phosphokina
se) 
WNL 
>ULN - 2.5 
x ULN 
>2.5 - 5 x 
ULN 
>5 - 10 x 
ULN 
>10 x ULN 
Amylase 
WNL 
>ULN - 1.5 
>1.5 - 2.0 x 
>2.0 - 5.0 x 
>5.0 x ULN 


 
42 
x ULN 
ULN 
ULN 
Lipase 
WNL 
>ULN - 1.5 
x ULN 
>1.5 - 2.0 x 
ULN 
>2.0 - 5.0 x 
ULN 
>5.0 x ULN 
Sinus 
bradycardia 
None 
asymptomati
c, not 
requiring 
treatment 
symptomatic
, but not 
requiring 
treatment 
symptomatic 
and 
requiring 
treatment 
life-
threatening 
(e.g., 
arrhythmia 
associated 
with CHF, 
hypotension, 
syncope, 
shock) 
Sinus 
tachycardia 
None 
asymptomati
c, not 
requiring 
treatment 
symptomatic
, but not 
requiring 
treatment 
symptomatic 
and 
requiring 
treatment of 
underlying 
cause 
- 
Conduction 
abnormality 
Atrio-
ventricular 
heart block 
None 
Asymptomat
ic, not 
requiring 
treatment 
(e.g. Mobitz 
type 1 
second-
degree AV 
block, 
Wenkebach) 
Symptomati
c, but not 
requiring 
treatment 
Symptomati
c and 
requiring 
treatment 
(e.g. Mobitz 
type II 
second 
degree AV 
block, third 
degree AV 
block 
Life-
threatening 
(e.g. 
arrhythmia 
associated 
with CHF, 
hypotension, 
syncope,  
shock 
Supraventric
ular 
arrhythmias( 
SVT/atrial 
fibrillation 
/flutter) 
None 
asymptomati
c, not 
requiring 
treatment 
symptomatic
, but not 
requiring 
treatment 
symptomatic 
and 
requiring 
treatment 
life-
threatening 
(e.g., 
arrhythmia 
associated 
with CHF, 
hypotension, 
syncope, 
shock) 
Cardiac-
ischemia/ 
infarction 
None 
non-specific 
T–wave 
flattening or 
changes 
asymptomati
c, ST– and 
T-wave 
changes 
suggesting 
ischemia 
angina 
without 
evidence of 
infarction 
acute 
myocardial 
infarction