Pharmacokinetics and safety of coformulated bictegravir, emtricitabine, and tenofovir alafenamide in children aged 2 years and older with virologically suppressed HIV: a phase 2/3, open-label, single-arm study.

BACKGROUND: Coformulated bictegravir, emtricitabine, and tenofovir alafenamide is a single-tablet regimen and was efficacious and well tolerated in children and adolescents with HIV (aged 6 years to <18 years) in a 48-week phase 2/3 trial. In this study, we report data from children aged at least 2 years and weighing 14 kg to less than 25 kg. METHODS: We conducted this open-label, multicentre, multicohort, single-arm study in South Africa, Thailand, Uganda, and the USA. Participants were virologically suppressed children with HIV, aged at least 2 years, weighing 14 kg to less than 25 kg. Participants received bictegravir (30 mg), emtricitabine (120 mg), and tenofovir alafenamide (15 mg) once daily, switching to bictegravir (50 mg), emtricitabine (200 mg), and tenofovir alafenamide (25 mg) upon attaining a bodyweight of at least 25 kg. The study included pharmacokinetic evaluation at week 2 to confirm the dose of coformulated bictegravir, emtricitabine, and tenofovir alafenamide for this weight band by comparing with previous adult data. Primary outcomes were bictegravir area under the curve over the dosing interval (AUCtau) and concentration at the end of the dosing interval (Ctau) at week 2, and incidence of treatment-emergent adverse events and laboratory abnormalities until the end of week 24 in all participants who received at least one dose of bictegravir, emtricitabine, and tenofovir alafenamide. This study is registered with ClinicalTrials.gov, NCT02881320. FINDINGS: Overall, 22 participants were screened (from Nov 14, 2018, to Jan 11, 2020), completed treatment with bictegravir, emtricitabine, and tenofovir alafenamide (until week 48), and entered an extension phase. The geometric least squares mean (GLSM) ratio for AUCtau for bictegravir was 7·6% higher than adults (GLSM ratio 107·6%, 90% CI 96·7-119·7); Ctau was 34·6% lower than adults (65·4%, 49·1-87·2). Both parameters were within the target exposure range previously found in adults, children, or both". Grade 3-4 laboratory abnormalities occurred in four (18%) participants by the end week 24 and six (27%) by the end of week 48. Drug-related adverse events occurred in three participants (14%) by the end of week 24 and week 48; none were severe. No Grade 3-4 adverse events, serious adverse events, or adverse events leading to discontinuation occurred by the end of week 24 and week 48. INTERPRETATION: Data support the use of single-tablet coformulated bictegravir (30 mg), emtricitabine (120 mg), and tenofovir alafenamide (15 mg) for treatment of HIV in children aged at least 2 years and weighing 14 kg to less than 25 kg. FUNDING: Gilead Sciences.

Switch to bictegravir/emtricitabine/tenofovir alafenamide from dolutegravir-based therapy.

OBJECTIVE: To evaluate the efficacy and safety of 96 weeks of bictegravir/emtricitabine/tenofovir alafenamide (B/F/TAF) treatment in participants switching from dolutegravir (DTG)-based therapy. DESIGN: Studies 1489 (NCT02607930) and 1490 (NCT02607956) were phase 3 randomized, double-blind, active-controlled, first-line therapy trials in people with HIV-1. After 144 weeks of DTG-based or B/F/TAF treatment, participants could enter a 96-week open-label extension (OLE) of B/F/TAF. METHODS: A pooled analysis evaluated viral suppression (HIV-1 RNA <50 copies/ml) and changes in CD4 + cell count at OLE Weeks 48 and 96, treatment-emergent resistance, safety, and tolerability after switch from a DTG-based regimen to B/F/TAF. Outcomes by prior treatment were summarized using descriptive statistics and compared by two-sided Wilcoxon rank sum test. RESULTS: At OLE Week 96, participants who switched to B/F/TAF ( N  = 519) maintained high levels of virologic suppression (99.5 and 99.1% in those switching from DTG/abacavir/lamivudine and DTG+F/TAF, respectively) and CD4 + cell count, with no treatment-emergent resistance to B/F/TAF. Twenty-one participants experienced drug-related adverse events after switching, with diarrhea, weight gain, and headache occurring most commonly. There were no cases of proximal renal tubulopathy, drug-related Grade 4 adverse events, or serious adverse events. Two participants discontinued B/F/TAF due to treatment-related adverse events. Participants who switched from DTG/abacavir/lamivudine experienced statistically significant greater weight gain than those who switched from DTG+F/TAF; however, median weight change from the blinded phase baseline to OLE Week 96 was numerically similar across treatment groups. CONCLUSION: This medium-term analysis demonstrates the safety and efficacy of switching to B/F/TAF from a DTG-containing regimen in people with HIV-1.

A study of the pharmacokinetics, safety, and efficacy of bictegravir/emtricitabine/tenofovir alafenamide in virologically suppressed pregnant women with HIV.

OBJECTIVE: The objective of this study was to assess the pharmacokinetics, safety, and efficacy and confirm the dose of once-daily bictegravir/emtricitabine/tenofovir alafenamide (BIC/FTC/TAF; B/F/TAF) during pregnancy. DESIGN: An open-label, multicenter, single-arm, phase 1b study (NCT03960645) was conducted in 33 virologically suppressed pregnant women with HIV-1. METHODS: Participants received B/F/TAF (50/200/25 mg) from the second or third trimester through ∼16 weeks postpartum. Steady-state maternal plasma pharmacokinetic samples were collected at the second and third trimesters and 6 and 12 weeks postpartum for BIC, FTC, and TAF. Neonates ( n  = 29) were followed from birth to 4-8 weeks with sparse washout pharmacokinetic sampling for BIC and TAF. The proportion of participants with HIV-1 RNA less than 50 copies/ml at delivery (missing = excluded) was evaluated. RESULTS: Mean areas under the concentration-time curve over the dosing interval (AUC tau ) for BIC, FTC, and TAF were lower during pregnancy versus postpartum but were closer to AUC tau values for nonpregnant adults with HIV reported in other studies. Geometric least-squares mean ratios for BIC, FTC, and TAF AUC tau during pregnancy versus postpartum ranged from 41 to 45%, 64 to 69% and 57 to 78%, respectively. Mean BIC trough concentrations during pregnancy were more than 6.5-fold greater than the protein-adjusted 95% effective concentration. In neonates, the median BIC half-life was 43 h. Virologic suppression was maintained in all adult participants throughout the study, with no virologic failure or treatment-emergent resistance to HIV-1, no discontinuations because of adverse events, and no perinatal transmission. CONCLUSION: Exposures to BIC, FTC, and TAF were lower during pregnancy than postpartum. However, mean BIC trough concentrations were maintained at levels indicative of efficacious exposure, and FTC/TAF data were concordant with published literature in this population. Pharmacokinetic and safety data, combined with maintenance of robust virologic suppression, suggest that once-daily B/F/TAF without dose adjustment is appropriate during pregnancy.

Bictegravir, emtricitabine, and tenofovir alafenamide versus dolutegravir, emtricitabine, and tenofovir disoproxil fumarate for initial treatment of HIV-1 and hepatitis B coinfection (ALLIANCE): a double-blind, multicentre, randomised controlled, phase 3 non-inferiority trial.

BACKGROUND: For most adults with HIV-1 and hepatitis B virus (HBV) coinfection, initial recommended treatment is a tenofovir-containing antiretroviral regimen, but no randomised studies have compared tenofovir disoproxil fumarate with tenofovir alafenamide. We aimed to investigate whether bictegravir, emtricitabine, and tenofovir alafenamide is non-inferior to dolutegravir, emtricitabine, and tenofovir disoproxil fumarate for viral suppression in individuals with HIV-1 and HBV coinfection at 48 and 96 weeks. METHODS: We did this randomised, double-blind, active-controlled, phase 3, non-inferiority trial at 46 outpatient centres in China, Dominican Republic, Hong Kong, Japan, Malaysia, South Korea, Spain, Taiwan, Thailand, Turkey, and the USA. Eligible participants were treatment-naive adults (aged ≥18 years) with plasma HIV-1 RNA of at least 500 copies per mL and plasma HBV DNA of at least 2000 IU/mL. Participants were randomly assigned (1:1) to receive daily oral bictegravir 50 mg, emtricitabine 200 mg, and tenofovir alafenamide 25 mg, or dolutegravir 50 mg, emtricitabine 200 mg, and tenofovir disoproxil fumarate 300 mg, each with corresponding matching placebo. Randomisation was stratified by hepatitis B e antigen (HBeAg) status (positive vs negative), HBV DNA (<8 vs ≥8 log10 IU/mL), and CD4 count (<50 vs ≥50 cells per µL) at screening. All investigators, participants, and staff providing treatment, assessing outcomes, and collecting data were masked to study treatment for 96 weeks. Coprimary endpoints were the proportion of participants with plasma HIV-1 RNA less than 50 copies per mL (defined by the US Food and Drug Administration snapshot algorithm) and plasma HBV DNA less than 29 IU/mL (using the missing-equals-failure approach) at week 48, with a prespecified non-inferiority margin of -12%. Coprimary endpoints were assessed in the full analysis set, which included all randomly assigned participants who received at least one dose of study drug and had at least one post-baseline HIV-1 RNA or HBV DNA result while on study drug. Safety endpoints were assessed in all randomly assigned participants who received at least one dose of study drug. This trial is registered with ClinicalTrials.gov, NCT03547908. FINDINGS: Between May 30, 2018 and March 16, 2021, 381 participants were screened, of whom 243 initiated treatment (121 in the receive bictegravir, emtricitabine, and tenofovir alafenamide group; 122 in the dolutegravir, emtricitabine, and tenofovir disoproxil fumarate group). At week 48, both endpoints met the criteria for non-inferiority: 113 (95%) of 119 participants in the bictegravir, emtricitabine, and tenofovir alafenamide group and 111 (91%) of 122 participants in the dolutegravir, emtricitabine, and tenofovir disoproxil fumarate group had HIV-1 RNA less than 50 copies per mL (difference 4·1, 95% CI -2·5 to 10·8; p=0·21), and 75 (63%) of 119 participants in the bictegravir, emtricitabine, and tenofovir alafenamide group versus 53 (43%) of 122 participants in the dolutegravir, emtricitabine, and tenofovir disoproxil fumarate group had HBV DNA suppression (difference 16·6, 5·9 to 27·3; nominal p=0·0023). Drug-related adverse events up to week 96 occurred in 35 (29%) of 121 participants in the bictegravir, emtricitabine, and tenofovir alafenamide group and 34 (28%) of 122 participants in the dolutegravir, emtricitabine, and tenofovir disoproxil fumarate group. One (1%) of 121 participants in the bictegravir, emtricitabine, and tenofovir alafenamide group reported a serious adverse event (cryptococcal meningitis attributed to immune reconstitution inflammatory syndrome) that was deemed to be treatment-related. INTERPRETATION: Coformulated bictegravir, emtricitabine, and tenofovir alafenamide is an effective therapy for adults with HIV-1 and HBV coinfection starting antiviral therapy. FUNDING: Gilead Sciences.

Bictegravir/emtricitabine/tenofovir alafenamide as initial treatment for HIV-1: five-year follow-up from two randomized trials.

Background: Bictegravir/emtricitabine/tenofovir alafenamide (B/F/TAF) is a single-tablet regimen recommended for HIV-1 treatment. The safety and efficacy of B/F/TAF as initial therapy was established in two Phase 3 studies: 1489 (vs dolutegravir [DTG]/abacavir/lamivudine) and 1490 (vs DTG + F/TAF). After 144 weeks of randomized follow-up, an open-label extension evaluated B/F/TAF to 240 weeks. Methods: Of 634 participants randomized to B/F/TAF, 519 completed the double-blinded treatment, and 506/634 (80%) chose the 96-week open-label B/F/TAF extension, which was completed by 444/506 (88%) participants. Efficacy was based on the secondary outcome of the proportion of participants with HIV-1 RNA <50 copies/mL at Week 240 by missing = excluded and missing = failure methods. All 634 participants who were randomized to B/F/TAF and received at least one dose of B/F/TAF were included in efficacy and safety analyses. (Study 1489: ClinicalTrials.govNCT02607930; EudraCT 2015-004024-54. Study 1490: ClinicalTrials.govNCT02607956; EudraCT 2015-003988-10). Findings: Of those with available virologic data, 98.6% (95% CI [97.0%-99.5%], 426/432) maintained HIV-1 RNA <50 copies/mL at Week 240 (missing = excluded); when missing virologic data were considered as failure, 67.2% (95% CI [63.4%-70.8%], 426/634) maintained HIV-1 RNA <50 copies/mL. Mean (SD) change in CD4+ count from baseline was +338 (236.2) cells/µL. No treatment-emergent resistance to B/F/TAF was detected. Adverse events led to drug discontinuation in 1.6% (n = 10/634) of participants (n = 5 with events considered drug-related). No discontinuations were due to renal adverse events. Median (IQR) total cholesterol increased 21 (1,42) mg/dL from baseline; the change in total cholesterol:HDL was 0.1 (-0.5,0.6). Median (IQR) weight change from baseline was +6.1 kg (2.0, 11.7) at Week 240. In Study 1489, hip and spine bone mineral density mean percent changes from baseline were ≤0.6%. Interpretation: Through 5 years of follow-up, B/F/TAF maintained high rates of virologic suppression with no treatment-emergent resistance and rare drug discontinuations due to adverse events. These results demonstrate the durability and safety of B/F/TAF in people with HIV. Funding: Gilead Sciences.

The frequency of adjusted renal dosing of tenofovir DF and its effects on patient outcomes.

Tenofovir disoproxil fumarate (TDF), a nucleotide reverse transcriptase inhibitor used in the treatment of human immunodeficiency virus (HIV) and hepatitis B, is renally eliminated and has been associated with renal toxicities. Dose adjustments are recommended for patients with creatinine clearance (CrCL) <50 mL/min. We retrospectively determined the frequency in which HIV clinic providers adjusted TDF doses in patients with CrCL <50 mL/min over a 2-year period and compared clinical outcomes in patients who had TDF dose adjustments based on CrCL <50 mL/min versus those who did not. Thirty-nine patients with CrCL <50 mL/min were identified. Dose-adjusted patients (N = 9) continued their TDF-based antiretroviral regimens for 21 months longer following the first CrCL < 50 mL/min (P = .0193) and had gains in CD4 cell counts over 12 months (P = .0009). There were no statistically significant differences in CrCL or percentage of patients with detectable HIV-1 RNA at 6 and 12 months following first CrCL <50 mL/min in those who did versus did not have a TDF dose adjustment. In summary, HIV providers often failed to dose-adjust TDF in patients with CrCL <50 mL/min, but dose-adjusted patients appeared to stay on their TDF-based regimens longer and have greater gains in CD4 cells. Larger, prospective studies are needed to validate these results.