Prospective Cohort of HIV/HBV-coinfected Patients in Europe

Study Overview
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Brief Summary
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The overall aim of the project is to establish an international multi-cohort research platform of HIV/HBV-coinfected individuals treated with tenofovir to improve our understanding of the determinants of treatment outcomes.

Detailed Description
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Hepatitis B virus (HBV) infection is a major cause of morbidity and mortality among human immunodeficiency virus (HIV)-infected individuals and the progression of liver disease is accelerated in this population compared to HBV-monoinfected individuals. Tenofovir disoproxil fumarate (TDF) or tenofovir alafenamide (TAF) as part of antiretroviral therapy (ART) suppresses HBV viral load in most patients. However, risk factors of suboptimal virological response to TDF/TAF and predictors of hepatitis B surface antigen (HBsAg) loss remain unclear. While novel drugs for HBV therapy are being developed, a more thorough understanding of the factors associated with optimal outcomes is urgent. Euro-B considers all HIV/HBV-coinfected participants from EuroSIDA, the Swiss HIV cohort study and French, Spanish and German HIV-HBV cohorts treated with TDF/TAF for inclusion. The overall aim of the project is to establish an international prospective multi-cohort research platform of HIV/HBV-coinfected individuals to improve our understanding of the determinants of treatment outcomes, including functional cure of HBV infection. Specifically, we aim to: evaluate HBV virological suppression, hepatitis B e antigen (HBeAg) and HBsAg loss as well as the course of quantitative HBsAg (qHBsAg) levels during TDF/TAF-containing antiretroviral therapy evaluate predictors of HBsAg loss and its correlation with Hepatitis B core-related antigen (HBcrAg) and pre-genomic RNA (pgRNA) levels explore risk factors for low-level HBV replication after 2 years of therapy describe changes in liver fibrosis stage and rates of transaminase normalization over time and according to HBV therapy outcome assess rates and reasons of treatment interruptions or changes.

Official Title
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Understanding Treatment Outcomes of HIV/HBV Coinfection: A Prospective Cohort of HIV/HBV-coinfected Patients in Europe

Conditions
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HIV Infections, Hepatitis B, Coinfection

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Study participant from contributing cohort 2 positive HBsAg tests more than 6 months apart At least 2 data points (baseline and 2 years after TDF/TAF start either as available data or stored sample Exclusion Criteria: None

Ages Eligible for Study
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Minimum Age: 16 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| HBV suppression | Proportion of participants achieving undetectable HBV DNA | 2 years of TDF/TAF-containing treatment and last available timepoint | 
| HBsAg loss | Proportion of participants with a negative HBsAg measurement | 2 years of TDF/TAF-containing treatment and last available timepoint | 
| HBeAg loss | Proportion of participants with a negative HBeAg measurement | 2 years of TDF/TAF-containing treatment and last available timepoint | 
| Transaminase normalization | Proportion of participants with transaminase normalization | 2 years of TDF/TAF-containing treatment and last available timepoint | 
| Liver fibrosis change | Proportion of participants with a change in liver fibrosis stage | 2 years of TDF/TAF-containing treatment and last available timepoint | 
| Treatment interruption or change | Assessments of rates and reasons for treatment interruptions or changes | 2 years of TDF/TAF-containing treatment and last available timepoint |