Effect of hepatitis B virus (HBV) surface-gene variability on markers of replication during treated human immunodeficiency virus-HBV infection in Western Africa

Functional Cure of Hepatitis B Virus Infection in Individuals With HIV-Coinfection: A Literature Review

In individuals infected with hepatitis B virus (HBV), the loss of hepatitis B surface antigen (HBsAg) is the ultimate therapeutic goal, which defines "functional cure." For individuals living with human immunodeficiency virus (HIV), functional cure occurs roughly 2 per 100 person-years during potent anti-HBV containing antiretroviral therapy. Although this rate may be higher than expected in treated HBV mono-infected individuals, rates of functional cure widely vary between studies (0.6-10.5 per 100 person-years). Similar to HBV mono-infection, the phase of HBV infection, HBV (sub-)genotypes and hepatitis B "e" Ag-negative variants are associated with functional cure in treated HIV-HBV co-infection. In specifically HIV-HBV co-infected individuals, strong increases in CD4+ T cell counts after treatment initiation have also been linked to functional cure, yet this finding is inconsistent across studies. Several markers directly or indirectly reflecting HBV activity are being developed to predict functional cure, such as quantification of HBsAg, hepatitis B core-related antigen, HBsAg protein composition, anti-hepatitis B core antibodies and interferon-gamma-inducible protein 10. Few have been assessed during treatment in HIV-HBV co-infected individuals and none have been validated to predict functional cure. Novel therapeutics for HBV cure are essential for individuals with HIV-HBV co-infection and need to be separately evaluated in this population.

Mortality in relation to hepatitis B virus (HBV) infection status among HIV-HBV co-infected patients in sub-Saharan Africa after immediate initiation of antiretroviral therapy

It is unknown how past and active hepatitis B virus (HBV) infection affect immunorecovery and mortality in people with HIV who initiate tenofovir-based antiretroviral therapy (ART). Using data collected between 2008 and 2015, we studied people with HIV in sub-Saharan Africa initiating immediate ART in the Temprano randomized control trial. We classified participants into HBV groups at ART initiation: hepatitis B surface antigen (HBsAg)-positive with HBV DNA ≥ 2,000 IU/ml; HBsAg-positive with HBV DNA < 2,000 IU/ml; isolated HBcAb-positive; resolved infection (HBsAb-positive/HBcAb-positive); and HBV non-immune/vaccinated (HBcAb-negative). We compared square-root CD4-cell count increases using mixed-effect, non-linear regression adjusted for age, sex, baseline CD4 cell count, and HIV RNA. We compared all-cause mortality using Bayesian parametric survival regression. Among 879 participants, 24 (2.7%) had HBsAg with high HBV DNA, 76 (8.6%) HBsAg with low HBV DNA, 325 (37.0%) isolated anti-HBcAb, 226 (25.7%) resolved HBV infection and 228 (25.9%) HBV non-immune/vaccinated. We found no significant difference in CD4 cell increases between HBV-infection groups after adjustment (p = 0.16). Participants with HBsAg and high HBV DNA had the highest incidence of all-cause mortality (1.9/100 person-years, 95% Credibile Interval [CrI] = 1.0-3.4). By comparison, incidence rates of mortality were reduced by 57% (95%CrI = -79%, -13%), 60% (95%CrI = -82%, -12%) and 66% (95%CrI = -84%, -23%) in those who had isolated anti-HBcAb-positive, resolved HBV infection and HBV non-immune/vaccinated, respectively. In conclusion, individuals with HIV and past HBV infection or isolated anti-HBcAb-positive serology, much like HBV non-immune/vaccinated, experience lower mortality than those with HBsAg and high HBV DNA. Additional HBV-related management would not be necessary for these individuals.