Tenofovir-containing regimen sustains high viral suppression in HIV-1/HBV coinfection

Treatment with either bictegravir/emtricitabine/tenofovir alafenamide (B/F/TAF) or dolutegravir + emtricitabine/tenofovir disoproxil fumarate (DTG + F/TDF) resulted in similarly high and sustained rates of viral suppression in adults with HIV-1* and HBV** coinfection, according to a prespecified secondary analysis of the ALLIANCE trial presented at IAS 2023.

At week 96, the proportion of patients who achieved HIV-1 RNA suppression (<50 copies/mL) and HBV DNA suppression (<29 IU/mL) were similarly high in both B/F/TAF and DTG + F/TDF groups (87 percent vs 88 percent; p_nominal=0.94 and 75 percent vs 70 percent; p_nominal=0.64, respectively). [IAS 2023, abstract 5514]

“International guidelines recommend a TDF- or TAF-containing antiretroviral regimen for most adults with HIV-1/HBV coinfection, but no randomized studies have compared these approaches in this population,” said Dr Anchalee Avihingsanon from the Thai Red Cross AIDS Research Centre in Bangkok, Thailand, who presented the study.

This ongoing, phase III trial analysed 243 adults with both HIV-1 and HBV (median age 32 years, 95.5 percent male) who had no previous HIV-1/HBV treatment. Participants were randomly assigned to receive either single-tablet regimen of B/F/TAF (50/200/25 mg; n=121) or two-tablet regimen of DTG + F/TDF (50 + 200/300 mg; n=122) daily in addition to placebo for 96 weeks.

With regard to other markers of anti-HBV activity, the rate of alanine aminotransferase normalization was significantly higher in the B/F/TAF group vs the DTG + F/TDF group at week 96 (72 percent vs 57 percent; p<0.01).

Patients treated with B/F/TAF also achieved significantly higher rates of HBeAg*** loss (38 percent vs 20 percent; p<0.01) and seroconversion (32 percent vs 15 percent; p<0.01) through week 96 compared with DTG + F/TDF.

Similarly, the rates of HBsAg⁺ loss and seroconversion were numerically higher with B/F/TAF than with DTG + F/TDF at week 96 (23 percent vs 14 percent and 9 percent vs 7 percent, respectively).

“This is an important finding in this study … as HBsAg loss and seroconversion are usually rare … a high rate of HBsAg loss and seroconversion in HIV-1 and HBV coinfection might be partly explained by the immune reconstitution hypothesis, in which after initiation of antiretroviral therapy for HIV-1, the immune system begins to reconstitute and the chance of clearing HBsAg increases,” the researchers said in a published paper. [Lancet HIV 2023;doi:10.1016/S2352-3018(23)00151-0]

In terms of safety, both B/F/TAF and DTG + F/TDF groups showed similar rates of any grade 3 or 4 adverse events (AEs; 96 percent for both groups) and serious AEs (14 percent vs 13 percent).

The incidence of any grade 3 or 4 laboratory abnormalities was also similar between the B/F/TAF and DTG + F/TDF groups (95 percent vs 94 percent).

“Overall, treatment with B/F/TAF and DTG + F/TDF resulted in high rates of HIV-1 and HBV viral suppression [which was] sustained over 96 weeks in adults who had both HIV-1 and HBV,” said Avihingsanon.

“Our data, combined with the lower impact of TAV vs TDF on bone and renal health, showed clinical benefits of the single-tablet regimen B/F/TAF for adults with HIV-1 and HBV coinfection initiating antiviral therapy,” she highlighted.