Objectives:

Primary Objective:

To identify and preselect patients with chronic HBV mono infection, who are undetectable for anti-Ad5 nAb, currently being treated with nucleo(t)sides, for participation in the TG1050.02 Phase1/1b First in Man (FIM) study.

Secondary Objectives:

To assess the prevalence of undetectable anti-Ad5 nAb in chronic HBV mono-infected patients.

Methodology:

Patients with chronic HBV mono-infection, who are currently being treated with nucleo(t)sides for their HBV infection, will be enrolled in this study to measure Ad5 nAb levels. A single peripheral blood collection (4 mL) will be obtained and Ad5 nAb titers will be measured by a central laboratory using a newly validated assay.

Inclusion Criteria:

• 18 through 65 years of age, inclusive
• Patients mono-infected with HBV and currently on HBV treatment for at least 2 years with either the nucleos(t)ide tenofovir (TDF) or entecavir (ENT)
• HBV DNA < lower limit of quantification (LLOQ) (eg, HBV deoxyribonucleic acid (DNA) < 20 IU/mL using the Roche COBAS TaqMan assay) within 6 last months
• Signed, written Independent Ethics Committee (IEC)-approved informed consent

Exclusion Criteria:

• Patients with either medical history or evidence of cirrhosis, as documented in the medical source, who had: a) any biopsy showing cirrhosis; or b) any transient elastography score of ≥ 10.5 kPa or Fibrosure® / FibroTest ® score of ≥ 0.48 with either test result within past 2 years.