By Marie Rosenthal, MS
Switching from a standard regimen of antiretroviral therapy to bictegravir-emtricitabine-tenofovir alafenamide (B/F/TAF; Biktarvy, Gilead Sciences) can be effective in Black Americans with HIV who are virologically suppressed, including those with preexisting resistance, according to a presentation at IDWeek 2020 (poster 1048).
Researchers reported 48-week results from the BRAAVE 2020 trial, a phase 3 clinical trial evaluating treatment responses of virologically suppressed adults living with HIV who self-identified as Black or African American following a switch to B/F/TAF from a variety of regimens that contained two nucleoside reverse transcriptase inhibitors (NRTIs) plus a third agent.
They took a closer look at this group because “African Americans continue to have the highest rates of HIV and AIDS in the U.S.,” said principal investigator Debbie P. Hagins, MD, FAPCR, the medical director of the CARE Centers of Southeast Georgia, Coastal Health District, Savannah. Yet, they remain underrepresented in clinical research for HIV, according to Kristen Andreatta, MSc, a senior associate scientist at Gilead, who also presented at IDWeek.
A total of 495 study participants were randomized 2:1 to switch to open-label B/F/TAF (330) or to stay on a regimen of two NRTIs plus a third agent (165) for 24 weeks, with a delayed switch to B/F/TAF until week 48, Hagins explained.
The patients ranged in age from 18 to 79 years. Of the patients, 32% were cisgender women and 2% were transgender women. Ten percent had a preexisting M184V/I mutation. Most of the people studied (62%) lived in the South. “Sites were selected to essentially mirror the prevalence of HIV among African Americans [in the United States],” she said.
The study demonstrated that at 48 weeks, treatment with B/F/TAF maintained high rates of virologic suppression in study participants and did not result in treatment-emergent resistance to any component of B/F/TAF.
At week 24, 1% (2/328) on B/F/TAF versus 2% (3/165) on the standard regimen had HIV-1 RNA of more than 50 copies/mL (difference, –1.2%; 95% CI, –4.8% to 0.9%), which demonstrated that B/F/TAF was noninferior to the standard regimen, Hagins said. Two people with preexisting primary integrase strand transfer inhibitor resistance were excluded from the analysis.
One hundred sixty-three patients assigned to the standard regimen and who completed treatment up to week 24 were switched to B/F/TAF and followed to week 48. At week 48, 1% (3/328) of those originally randomized to B/F/TAF and none in the switch group had a viral load of 50 copies/mL or higher.
In another analysis of the BRAAVE 2020 trial, researchers found similar virologic suppression rates were achieved regardless of the presence of preexisting drug resistance substitutions.
Through 48 weeks, 99% of study participants in the B/F/TAF group (324/327) and 100% of those in the delayed-switch group (162/162) maintained viral loads less than 50 copies/mL (abstract 109), according to Andreatta, who presented these data.
“I want to note that we previously found that Black race was one factor associated with preexisting M184V/I in virologically suppressed clinical trial participants,” Andreatta said. “This is significant because the M184V/I mutation is very common after treatment failure and confers high level of resistance to emtricitabine and lamivudine, one of which is a component of most ARV [antiretroviral] regimens, including B/F/TAF.”
The most notable preexisting resistance seen were M184V/I, thymidine analog–associated mutations and non-NRTI regimens. Despite this, patients on the B/F/TAF regimen maintained high rates of virologic suppression through 48 weeks, Andreatta said. No failures with de novo resistance were seen.
“As drug resistance builds, treatment options become more limited, sometimes leading to less desirable, but often necessary, complicated treatment regimens. Again, lending itself to further adherence challenges,” Hagins said, adding that the study demonstrated that B/F/TAF could address that need.
“Black and African Americans in this country have the highest rates of new HIV infections every year compared to other races. Adding to that burden are other inequalities such as lack of health insurance, difficulties navigating the health care system, and poverty, all of which contribute to higher rates of drug resistance,” Hagins said.
The use of B/F/TAF in individuals with a history of treatment failure or known resistance to the components of the medication is investigational, the company said.
—Haggins reported financial relationships with Gilead Sciences, Janssen, Merck and ViiV Healthcare. Andreatta reported no related financial relationships outside her employment.
