Bictegravir-Based Treatment Wins for HIV/HBV Co-Infections

MONTREAL -- For individuals infected by both HIV and hepatitis B virus (HBV), the choice of which virus-suppressing therapy to use can make a difference in outcomes, according to 48-week results of the phase III ALLIANCE results reported here.

In a head-to-head comparison, fixed doses of either bictegravir, emtricitabine, and tenofovir alafenamide (Biktarvy) or dolutegravir, emtricitabine, and tenofovir disoproxil fumarate were both able to suppress HIV to undetectable levels in the vast majority of patients (95% vs 91%, P=0.21), reported Anchalee Avihingsanon, MD, PhD, of Thai Red Cross AIDS Research Center in Bangkok.

But the bictegravir-based therapy was superior for suppressing HBV at 48 weeks, Avihingsanon said in her presentation at the International AIDS Conference.

Among 241 adults with HIV-1/HBV co-infections initiating first-line antiviral therapy, 63% of the patients on the bictegravir-based regimen were able to reduce the level of HBV DNA to less than 29 IU/mL, compared with 43.4% of those on the dolutegravir-based regimen (P=0.0023).

She called the bictegravir-based regimen "a safe and effective treatment" for this patient population, adding that both treatment options in ALLIANCE were well tolerated.

Avihingsanon noted that twice as many patients taking the bictegravir formulation had hepatitis B surface antigen (HBsAg) seroconversion compared with those on the dolutegravir regimen (23% vs 11%), though the difference did not reach statistical significance.

By week 48, liver enzymes had normalized in 73.3% of the patients on bictegravir compared with 55.3% of those on dolutegravir (P<0.05), she reported.

"Chronic hepatitis B affects about 8% of people with HIV, and HIV/hepatitis B virus co-infection rates can reach 25% in areas where both viruses are endemic," said Avihingsanon, adding that these patients have higher risks for cirrhosis and liver cancer than people with an HBV infection alone.

People with these co-infections should receive treatment to suppress both viruses, she emphasized.

Current international guidelines recommend the following:

• Prior to initiation of antiretroviral therapy, all individuals who test positive for HBsAg should be tested for HBV DNA using a quantitative assay to determine the level of HBV replication

• Because emtricitabine, lamivudine, and tenofovir disoproxil fumarate have activity against HIV and HBV, if HBV or HIV treatment is needed, antiretroviral therapy should be initiated with the combination of tenofovir/emtricitabine or tenofovir/lamivudine as the nucleoside analogue reverse transcriptase inhibitor backbone of a fully suppressive antiretroviral regimen

• If HBV treatment is needed and tenofovir cannot be used safely, then entecavir in addition to a fully suppressive antiretroviral regimen is the recommended alternative treatment option

Avihingsanon noted that while both tenofovir disoproxil fumarate and tenofovir alafenamide are approved for treatment combinations, until the ALLIANCE study, regimens containing these nucleotide reverse transcriptase inhibitors had not been compared in a clinical trial of people with the co-infection who were initiating treatment.

ALLIANCE recruited patients internationally, but most heavily in Thailand, China, and Malaysia (88% of participants were Asian). The median age of the patients in the study was 32. Just 9% of the patients on bictegravir were female at birth, as were 2% of those in the dolutegravir arm. Median CD4-positive cell counts were about 240 cells/mL.

To be eligible for the trial, HIV viral load had to have been at least 500 copies/mL at diagnosis, HBV DNA had to have been at least 2,000 IU/mL, and patients were required to have good renal function.

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