Approved September 11, 2012

Clinical Trial of /Peginterferon in Immune Tolerant Children with Chronic HBV Infection for Health Care Providers Rationale: HBV infection results in and hepatocellular carcinoma (HCC) in 1.5 and 0.25-1% of patients during childhood (1, 2). The incidence of HCC increases over time and is as high as 30% for the lifetime risk (3, 4). The lifetime risk for liver cancer is highest for newborns who acquire HBV from their mothers. Persistent presence of HBeAg and persistently high serum HBV DNA levels have been shown to be associated with increased risk of HCC (see figures below). Treatment of immune tolerant HBV with single agents is not effective but there are now two small scale uncontrolled studies showing that treatment for a few weeks with a () followed by the combination of and lamivudine resulted in HBeAG seroconversion and HBV DNA loss in about 25% of patients (5). However, it is very important to do a prospective large-scale multi-center study before this approach can be universally applied.

Cumulative Incidence of Hepatocellular Carcinoma by Serum HBV DNA Level

Chen CJ et al. , JAMA 2006; 295: 65-73 Pediatric Immune Tolerant 09/11/2012 Page 1

Approved September 11, 2012

Pediatric B in Immune Tolerant Children: To determine whether treatment with 8 weeks of entecavir followed by 40 weeks of both entecavir and peginterferon alfa-2a leads to an increased rate of sustained virologic response (HBeAg loss and HBV DNA <1000 IU/ml) 48 weeks after cessation of therapy, in children age 3-<18 years who are in the immune tolerant phase of chronic (CHB) infection, when compared to no treatment which is the current standard of care.

Type of study: Randomized controlled treatment trial

Who is conducting the research study? The pediatric HBV Immune Tolerant trial is conducted by pediatric investigators in the Hepatitis B Research Network (HBRN) at various locations in the United States and Canada (http://www.hepbnet.org/ ).The National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) at the National Institutes of Health (NIH) is providing the funding for this study. Bristol-Myers Squibb is providing entecavir and Roche Genentech is providing peginterferon.

Specific Aims HBeAg loss and HBV DNA ≤1,000 IU/mL at the time of last follow up 48 weeks after end-of-treatment (week 96). Achieve the following at the end of treatment (week 48) and sustain these responses at the end of follow-up week 96: a. Cumulative HBsAg loss (as assessed by a new assay to quantify surface antigen) b. HBeAg loss (as assessed by a new assay to quantify e antigen) c. HBeAg seroconversion d. HBsAg seroconversion e. ALT ≤40 IU/L for males, ≤35 IU/L for females f. HBV DNA ≤1000 IU/mL g. HBV DNA <20 IU/mL (LLOQ of COBAS Ampliprep/COBAS TaqMan HBV v2.0 test) h. Absence of detectable -resistance HBV mutations i. Growth parameters (weight, height, BMI, Tanner scores)

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Approved September 11, 2012

Enrollment objective 250 subjects with 125 subjects in the treatment arm and 125 in the control arm. Subjects have to be enrolled in the Pediatric HBV cohort study of this Hepatitis B Research Network to participate in this trial.

1. Inclusion criteria 3 to <18 years at time of randomization (day 0). 2. Documented chronic HBV 3. Presence of HBeAg in serum 4. Serum HBV DNA level >107 IU/mL on at least two occasions at least 12 weeks apart 5. ALT ≤40 IU/l in males or ≤35 IU/l in females

Exclusion criteria 1. Presence of infection at screening with HCV, HDV, or HIV. 2. Presence of another cause of liver disease or HCC (serum alpha-fetoprotein >50ng /ml). 3. Evidence of decompensated liver disease (Childs B-C). 4. History or other evidence of a medical condition associated with chronic liver disease 5. Females who are pregnant or breastfeeding. 6. Adolescent females unwilling or unable to use an acceptable method of contraception 7. Children currently breastfeeding 8. Malignancy or other significant medical or psychiatric illness which, in the opinion a study physician, may interfere with participant treatment, assessment or compliance with the study protocol. 9. Previous liver or other organ transplantation including engrafted bone marrow transplant. 10. Hematological abnormalities during the screening period that contraindicate full dosing with study drugs, e.g absolute neutrophil count < 1.5 x 109 cells/L or platelet count < 120 x 109 cells/L. 11. Known allergy to study drugs; peginterferon alfa-2a or entecavir. 12. Treatment with systemic acyclovir or within the previous 6 months. 13. Need for ongoing use of any antivirals with activity against HBV during the course of the study or history of receiving treatment for HBV. 14. Any use of illegal drugs OR use of alcoholic beverages 15. Concomitant use of complementary or alternative medications purported to have antiviral activity. 16. During the treatment phase of the study, a participant may not be co-enrolled in another clinical trial where an investigational drug is administered.

Data to be collected The data to be collected from patients enrolled in this study will describe baseline demographics, symptoms of liver disease, intercurrent illnesses, and findings on physical examination. Blood work will be drawn to measure markers of viral and liver disease status, assessment of drug adverse effects, and for storage of serum.

Treatment Study subjects will be randomly assigned 1: 1 to one of the following arms: Treatment arm: Entecavir (liquid or tablet) once daily for 48 weeks and Peginterferon alfa-2a subcutaneously once weekly for 40 weeks beginning 8 weeks after entecavir monotherapy). Control arm: Standard of care (no treatment/untreated control arm).

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Approved September 11, 2012 Follow-up frequency Participants in treatment arm will be assessed in person at weeks 4, 8, 10, 12, 16, 20, 24, 36, 48, 52, 56, 60, 72, 84 and 96, and receive telephone assessment at weeks 14, 28, 32, 40, 44. Participants in the untreated control group will be seen at weeks 8, 12, 20, 36, 48, 72, and 96.

Compassionate combination therapy It will take about 4 years to enroll all patients and to reach the study endpoint for all and thus to determine if this combination therapy is effective. If it is effective, then patients in the control arm who are still eligible and who wish to undergo combination therapy will be offered this therapy.

Mechanism of Anti HBV Action of Various Antiviral Agent (Note the IFN blocks entry, uncoating and translation; and the nucleosides, e.g. Entecavir, block viral DNA synthesis)

References 1. Bortolotti F, Calzia R, Vegnente A et al. Chronic hepatitis in childhood: the spectrum of the disease. Gut 1988;29:659-64. 2. Wen WH, Chang MH, Hsu HY et al. The development of hepatocellular carcinoma among prospectively followed children with chronic infection. J Pediatr 2004;144:397- 9. 3. Bosch FX, Ribes J, Cleries R et al. Epidemiology of hepatocellular carcinoma. Clin Liver Dis 2005;9:191-211. 4. Lok AS, McMahon BJ. Chronic hepatitis B: update 2009. Hepatology 2009;50:661-2. 5. D'Antiga L, Aw M, Atkins M et al. Combined lamivudine/interferon-alpha treatment in "immunotolerant" children perinatally infected with hepatitis B: a pilot study. J Pediatr 2006;148:228-33.

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