A Study to Collect Blood Biomarker Samples From Participants With Chronic Hepatitis B (CHB) Who Received Treatment With Pegasys (Peginterferon Alfa-2a) ± Nucleoside/Nucleotide Analogue

A Phase IV, Blood Sample Collection Study For Exploratory Evaluation of the Association of Single Nucleotide Polymorphisms With Treatment Responses From Subjects With HBe-Antigen Positive or Negative Chronic Hepatitis B, Who Received Therapy for Hepatitis B With Peginterferon Alfa-2a 40kD (Peg-IFN) ± Nucleos(t)Ide Analogue

This Phase 4 study is designed for the collection of blood biomarker samples from participants who have completed CHB treatment with at least 24 weeks of a pegylated interferon alfa-2a (Peg-IFN alfa-2a) containing regimen and at least 24 weeks post-treatment follow-up. Participants may be enrolled from historical studies supported or sponsored by Roche, ongoing studies supported or sponsored by Roche, or from general medical practice. The follow-up of individuals who choose to participate in this study will be in accordance with the ongoing studies or with the general medical practice of the physician. Data from whole blood deoxyribonucleic acid (DNA) samples collected in the GV28555 study or available from previously collected Roche Clinical Repository (RCR) samples will be used for combined analysis with data from other applicable studies. Procedures will include blood sample collection (not applicable for participants who previously have consented and donated RCR DNA samples) and medical record capture.

Inclusion Criteria:

• Adults greater than or equal to (≥) 18 years of age
• CHB
• Previously enrolled in a Roche study and treated for CHB for ≥24 weeks with Peg-IFN ± nucleoside analogue (lamivudine or entecavir) or Peg-IFN ± nucleotide analogue (adefovir) and with ≥24 weeks post-treatment follow-up; or
• Treated in general practice for CHB with Peg-IFN according to standard of care and in line with the current Summary of Product Characteristics (SmPC)/local labeling who have no contraindication to Peg-IFN therapy as per local label and have been treated with Peg-IFN for ≥24 weeks and have ≥24 week post-treatment response available at the time of blood sample collection

Exclusion Criteria:

• Hepatitis A, hepatitis C, or human immunodeficiency virus (HIV) infection