Triple Therapy Maintains HIV Viral Suppression in Patients With Mutation, Prior Virologic Failure

Switching to coformulated bictegravir, emtricitabine, and tenofovir alafenamide (BIC/FTC/TAF) maintained HIV viral suppression in adults with prior virological failures and with the K65N/R mutation, according to a study published in the International Journal of Infectious Diseases.

According to the authors, this study shows BIC/FTC/TAF may be an option for simplification following viral suppression.

The retrospective study included 72 people living with HIV (PLWH) 20 years and older with emergent K65N/R mutation who experienced previous virologic failures.

All participants received HIV care across 10 designated hospitals around Taiwan between November 1, 2019, and June 30, 2022. All participants were male, and the mode of HIV transmission was predominantly male-to-male sexual contact (91.6%).

Participants were eligible to switch to BIC/FTC/TAF after having achieved plasma HIV RNA load (PVL) less than 200 copies/mL for at least 3 months and were excluded if integrase inhibitor resistance-associated mutations were detected.

Of the 72 PLWH identified, 42 (59.7%) had concurrent M184V/I and 9 (12.5%) had at least 1 thymidine analogue mutation. The median (IQR) duration of HIV viral suppression was 4.7 (2.3-5.8) years. Most (97.2%) had PVL less than 50 copies/mL before switching.

After a median (IQR) observation of 98.6 (77.9-120.3) weeks, 68 (94.4%) participants continued BIC/FTC/TAF.

At week 48, the authors found the rate of losing virologic control was 2.8%, with only 2 participants experiencing this primary end point. Additionally, M184V/I was not associated with viral rebound.

Additionally, most (87.5%) PLWH in the study maintained virological suppression at week 48, and the incidence of viral rebound to more than 200 copies/mL was low at 2.2 per 100 person-years during the study period.

Limitations of the study include its single-arm retrospective observational design, lack of HIV RNA assessments at uniform time points, and some discontinuation due to the COVID-19 pandemic.

The authors also did not have data on PLWH who were eligible to switch but did not, nor did they have the resistance testing results of those experiencing viral rebound.

Additionally, these results may not be generalizable to PLWH who are not adherent to antiretroviral therapy.

Despite these limitations, the authors concluded this study demonstrated that BIC/FTC/TAF was effective in maintaining viral suppression for PLWH with K65N/R mutation.

“Given the good tolerability, low toxicity, reduced pill burden and high genetic barrier to resistance, BIC/FTC/TAF could be a therapeutic option for second-line treatment simplification,” they said.

Reference

Tsai MS, Sun HY, Chen CP, et al. Switching to coformulated bictegravir, emtricitabine, and tenofovir alafenamide maintained viral suppression in adults with historical virological failures and K65N/R mutation. Int J Infect Dis. Published online November 13, 2022. doi:10.1016/j.ijid.2022.11.012