Antiretroviral drug dolutegravir induces inflammation at the mouse brain barriers.

Integrase strand transfer inhibitors (INSTIs) based antiretroviral therapy (ART) is currently used as first-line regimen to treat HIV infection. Despite its high efficacy and barrier to resistance, ART-associated neuropsychiatric adverse effects remain a major concern. Recent studies have identified a potential interaction between the INSTI, dolutegravir (DTG), and folate transport pathways at the placental barrier. We hypothesized that such interactions could also occur at the two major blood-brain interfaces: blood-cerebrospinal fluid barrier (BCSFB) and blood-brain barrier (BBB). To address this question, we evaluated the effect of two INSTIs, DTG and bictegravir (BTG), on folate transporters and receptor expression at the mouse BCSFB and the BBB in vitro, ex vivo and in vivo. We demonstrated that DTG but not BTG significantly downregulated the mRNA and/or protein expression of folate transporters (RFC/SLC19A1, PCFT/SLC46A1) in human and mouse BBB models in vitro, and mouse brain capillaries ex vivo. Our in vivo study further revealed a significant downregulation in Slc19a1 and Slc46a1 mRNA expression at the BCSFB and the BBB following a 14-day DTG oral treatment in C57BL/6 mice. However, despite the observed downregulatory effect of DTG in folate transporters/receptor at both brain barriers, a 14-day oral treatment of DTG-based ART did not significantly alter the brain folate level in animals. Interestingly, DTG treatment robustly elevated the mRNA and/or protein expression of pro-inflammatory cytokines and chemokines (Cxcl1, Cxcl2, Cxcl3, Il6, Il23, Il12) in primary cultures of mouse brain microvascular endothelial cells (BBB). DTG oral treatment also significantly upregulated proinflammatory cytokines and chemokine (Il6, Il1ß, Tnfα, Ccl2) at the BCSFB in mice. We additionally observed a downregulated mRNA expression of drug efflux transporters (Abcc1, Abcc4, and Abcb1a) and tight junction protein (Cldn3) at the CP isolated from mice treated with DTG. Despite the structural similarities, BTG only elicited minor effects on the markers of interest at both the BBB and BCSFB. In summary, our current data demonstrates that DTG but not BTG strongly induced inflammatory responses in a rodent BBB and BCSFB model. Together, these data provide valuable insights into the mechanism of DTG-induced brain toxicity, which may contribute to the pathogenesis of DTG-associated neuropsychiatric adverse effect.

Bictegravir/emtricitabine/tenofovir alafenamide in paediatrics: Real-life experience from a French cohort (2019-2023).

OBJECTIVES: Although widely recommended, data on bictegravir/emtricitabine/tenofovir alafenamide (BIC/FTC/TAF) efficacy in HIV-1-infected children/adolescents are mainly extrapolated from studies in adults and one paediatric trial in which subjects have good treatment adherence. This study aimed to provide data about the risk of virological failure (VF) and acquired genotypic resistance in children and adolescents receiving BIC/FTC/TAF in a real-world setting. METHODS: This retrospective monocentric study included 74 paediatric patients who received BIC/FTC/TAF during ≥6 months in 2019-2023. VF was defined as not achieving a plasma viral load <50 copies/mL within 6 months of BIC/FTC/TAF initiation or as experiencing virological rebound ≥50 copies/mL. RESULTS: Most patients were antiretroviral therapy (ART)-experienced (93.2%), previously exposed to integrase inhibitors (85.1%) and displayed viral suppression at baseline (67.6%). Their median age was 11.2 years [interquartile range (IQR): 8.8-15.2]. BIC/FTC/TAF introduction reduced treatment burden in most ART-experienced subjects. Genotypic susceptibility score of BIC/FTC/TAF was ≥2 in all cases. Median follow-up was 40 months (IQR: 21-46). VF occurred in 28 people (37.8%), more frequently in the case of VF versus viral suppression at baseline (68% vs. 26%, P = 0.02). BIC/FTC/TAF was interrupted for suspected intolerance in only one case (1.4%). Nucleoside reverse transcriptase inhibitor (NRTI) mutation (T69D/N) emerged in one patient (3.6% of VF) after 47 months of continuous detectable viraemia while on ART. No acquisition of mutations in the integrase gene was observed. CONCLUSION: Because of its high genetic barrier to resistance, BIC/FTC/TAF could be especially useful in the paediatric population, in which the risk of poor treatment adherence and VF is high.

Metabolic effects of switching to Biktarvy (B/F/TAF) in patients with HIV-1 treated with antiretroviral regimens that do not include tenofovir disoproxil fumarate (TDF) or tenofovir alafenamide (TAF): The Metabic study.

BACKGROUND: Studies on switching to tenofovir alafenamide (TAF)-based regimens raise concerns about a worse metabolic profile in people with HIV, even though most received tenofovir disoproxil fumarate (TDF) in their previous regimen. This study aims to evaluate changes in lipid fractions, glucose, and serum markers for hepatic steatosis (HS) after switching from a TDF- or TAF-sparing regimen to bictegravir/emtricitabine/TAF (B/F/TAF). METHODS: We performed a retrospective cohort study of people with HIV who switched to B/F/TAF from TDF- or TAF-sparing regimens between January 2019 and May 2022 with at least 6 months of follow-up. The primary endpoint was the absolute change in lipid fractions at 6 months. Secondary outcomes were changes in lipid fractions at 12 months and changes in other metabolic parameters (glucose, creatinine, and HS based on the triglyceride-to-glucose [TyG] ratio at 6 and 12 months). Changes were analysed using mixed linear regression models with random intercept and time as a fixed effect. RESULTS: The study included 259 people with HIV (median age 55 [interquartile range (IQR) 47-60] years; 80% male; 88% Caucasian; CD4+ T-cell count 675 [IQR 450-880] cells/mm3; 84.3% HIV-RNA <50 copies/mL). In total, 63 patients (30%) had hypertension, 93 (44%) dyslipidaemia, 30 (14%) diabetes, and 45% obesity/overweight. Most (60%) switched from integrase inhibitor-based regimens, and 21% switched from a boosted regimen. At 6 months, significant reductions were observed in total cholesterol (-7.64 mg/dL [95% confidence interval (CI) -13.52 to -1.76; p = 0.002]), triglycerides (-23.4 [95% CI -42.07 to -4.65]; p = 0.003), and TyG ratio (-0.14 [95% CI -0.23 to -0.05]; p < 0.001). CONCLUSION: In our real-life cohort, the effect of switching TDF-/TAF-sparing regimens to triple therapy with B/F/TAF improved total cholesterol, triglycerides, and serum markers of HS at 6 months and was neutral for the remaining metabolic parameters at 12 months.

Twelve-month effectiveness and safety of bictegravir/emtricitabine/tenofovir alafenamide in people with HIV: Real-world insights from BICSTaR cohorts.

BACKGROUND: Real-world evidence is an essential component of evidence-based medicine. The aim of the BICSTaR (BICtegravir Single Tablet Regimen) study is to assess effectiveness and safety of bictegravir/emtricitabine/tenofovir alafenamide (B/F/TAF) in antiretroviral treatment-naïve (TN) and treatment-experienced (TE) people with HIV. METHODS: BICSTaR is a prospective, observational cohort study. Participants (≥18 years) are being followed for 24 months. A pooled analysis is presented at 12 months, with the primary endpoint of effectiveness (HIV-1 RNA <50 copies/mL) and secondary endpoints of safety and tolerability (as per protocol). An exploration of patient-reported outcome measures using standardized questionnaires is included. RESULTS: Between June 2018 and May 2021, 1552 people with HIV were enrolled across 12 countries. The analysed population comprised 1509 individuals (279 TN, 1230 TE); most were white (76%), male (84%) and had one or more comorbid conditions (68%). Median age was 47 years. After 12 months of B/F/TAF treatment, HIV-1 RNA was <50 copies/mL in 94% (221/236) of TN participants and 97% (977/1008) of TE participants. Median CD4 cell count increased by 214 cells/µL (p < 0.001) in TN participants and 13 cells/µL (p = 0.014) in TE participants; median CD4/CD8 ratios increased by 0.30 and 0.03, respectively (both p < 0.001). Persistence was high at 12 months (TN, 97%; TE, 95%). No resistance to B/F/TAF emerged. Study drug-related adverse events occurred in 13% of participants through 12 months, leading to B/F/TAF discontinuation in 6%. CONCLUSIONS: The findings of this study provide robust real-world evidence to support the broad use of B/F/TAF in both TN and TE people with HIV.

Safety and adherence of bictegravir/emtricitabine/tenofovir alafenamide for HIV post-exposure prophylaxis among adults in Guiyang China: a prospective cohort study.

BACKGROUND: The effectiveness of post-exposure prophylaxis (PEP) depends on participants adherence, making it crucial to assess and compare regimen options to enhance human immunodeficiency virus (HIV) prophylaxis strategies. However, no prospective study in China has shown that the completion rate and adherence of single-tablet regimens in HIV PEP are higher than those of multi-tablet preparations. Therefore, this study aimed to assess the completion rate and adherence of two HIV PEP regimens. METHODS: In this single-center, prospective, open-label cohort study, we included 179 participants from May 2022 to March 2023 and analyzed the differences in the 28-day medication completion rate, adherence, safety, tolerance, and effectiveness of bictegravir/emtricitabine/tenofovir alafenamide (BIC/FTC/TAF) and tenofovir disoproxil fumarate, emtricitabine, and dolutegravir (TDF/FTC + DTG). RESULTS: The PEP completion rate and adherence were higher in the BIC/FTC/TAF group than in the TDF/FTC + DTG group (completion rate: 97.8% vs. 82.6%, P = 0.009; adherence: 99.6 ± 2.82% vs. 90.2 ± 25.29%, P = 0.003). The incidence of adverse reactions in the BIC/FTC/TAF and TDF/FTC + DTG groups was 15.2% and 10.3% (P = 0.33), respectively. In the TDF/FTC + DTG group, one participant stopped PEP owing to adverse reactions (1.1%). No other participants stopped PEP due to adverse events. CONCLUSIONS: BIC/FTC/TAF and TDF/FTC + DTG have good safety and tolerance as PEP regimens. BIC/FTC/TAF has a higher completion rate and increased adherence, thus, is recommended as a PEP regimen. These findings emphasize the importance of regimen choice in optimizing PEP outcomes. TRIAL REGISTRATION: The study was registered in the Chinese Clinical Trial Registry (registration number: ChiCTR2200059994(2022-05-14), https://www.chictr.org.cn/bin/project/edit?pid=167391 ).

The G118R plus R263K Combination of Integrase Mutations Associated with Dolutegravir-Based Treatment Failure Reduces HIV-1 Replicative Capacity and Integration.

Human immunodeficiency virus (HIV) treatment with antiretroviral regimens containing integrase strand transfer inhibitors such as dolutegravir (DTG) and bictegravir (BIC) offers high levels of protection against the development of drug resistance mutations. Despite this, resistance to DTG and BIC can occur through the development of the R263K integrase substitution. Failure with DTG has also been associated with the emergence of the G118R substitution. G118R and R263K are usually found separately but have been reported together in highly treatment-experienced persons who experienced treatment failure with DTG. We used cell-free strand transfer and DNA binding assays and cell-based infectivity, replicative capacity, and resistance assays to characterize the G118R plus R263K combination of integrase mutations. R263K reduced DTG and BIC susceptibility ~2-fold, in agreement with our previous work. Single-cycle infectivity assays showed that G118R and G118R plus R263K conferred ~10-fold resistance to DTG. G118R alone conferred low levels of resistance to BIC (3.9-fold). However, the G118R plus R263K combination conferred high levels of resistance to BIC (33.7-fold), likely precluding the use of BIC after DTG failure with the G118R plus R263K combination. DNA binding, viral infectivity, and replicative capacity of the double mutant were further impaired, compared to single mutants. We propose that impaired fitness helps to explain the scarcity of the G118R plus R263K combination of integrase substitutions in clinical settings and that immunodeficiency likely contributes to its development.

Bictegravir/emtricitabine/tenofovir alafenamide in patients with genotypic NRTI resistance.

BACKGROUND: Bictegravir/emtricitabine/tenofovir alafenamide (B/F/TAF) is approved for treatment of HIV without known resistance to its components. Several studies have demonstrated efficacy of B/F/TAF in patients with nucleoside reverse transcriptase inhibitor (NRTI) resistance-associated mutations (RAMs), mainly identified by proviral DNA testing, but data on the efficacy of B/F/TAF in patients with NRTI RAMs identified in viraemic plasma are limited. METHODS: We used a retrospective analysis of patients receiving B/F/TAF identified by searching electronic health records with eligibility confirmed by review of individual patient records. Patients included were ≥ 18 years, had 2019 International Antiviral Socitey-USA (IAS-USA) major RAMs affecting NRTIs detected in viraemic plasma prior to starting B/F/TAF and one or more HIV viral load (VL) after starting B/F/TAF. RESULTS: In all, 50 patients met the study criteria: mean age of 54 years, mean proximal CD4 count of 609 cells/µL, 64% male. A total of 46 were virologically suppressed (< 200 copies/mL) when B/F/TAF was initiated, two were treatment-naïve, one stopped prior antiretroviral therapy (ART) and one had a VL of 961 HIV-1 RNA copies/mL on ART. Twenty-nine had one NRTI RAM (24 were M184V/I), nine had two NRTI RAMs, three had three NRTI RAMs, four had four NRTI RAMs, two had five NRTI RAMs, one had six NRTI RAMs, one had seven RAMs and one had eight NRTI RAMs. At the last VL on B/F/TAF, a mean of 18.6 months after starting B/F/TAF, 49 out of 50 had VL < 100 copies/mL and one had a VL of 208 copies/mL at 11 months but only filled 5 months of B/F/TAF. CONCLUSIONS: B/F/TAF was effective in maintaining HIV VL suppression in patients with previously documented NRTI RAMs without integrase resistance.

Bictegravir/emtricitabine/tenofovir alafenamide in older individuals with HIV: Results of a 96-week, phase 3b, open-label, switch trial in virologically suppressed people ≥65 years of age.

OBJECTIVES: Bictegravir/emtricitabine/tenofovir alafenamide (B/F/TAF) is an effective treatment for HIV-1 infection; however, clinical trial data in older people living with HIV (PLWH) are lacking. The primary 24-week and secondary 48-week analyses of study GS-US-380-4449 (NCT03405935), which assessed the efficacy and safety of switching to B/F/TAF in older PLWH, have been published. Here we report the results of the final 96-week analyses from the study. METHODS: In this 96-week, phase 3b, open-label, single-arm trial, virologically suppressed PLWH aged ≥65 years switched from elvitegravir/cobicistat/emtricitabine/tenofovir alafenamide or a tenofovir disoproxil fumarate-based regimen to B/F/TAF. Viral suppression, resistance, immune response, safety, tolerability and adherence were evaluated through week 96. RESULTS: Of 90 participants screened, 86 were enrolled and switched to B/F/TAF. No participants had HIV-1 RNA ≥50 copies/ml (by FDA Snapshot algorithm) at weeks 72 or 96; virologic suppression rates were 94.2% (81/86; 95% CI 87.0-98.1) and 74.4% (64/86; 95% CI 63.9-83.2), respectively. No treatment-emergent resistance was observed, and CD4 counts remained stable. There were no study drug-related serious adverse events. Three participants experienced drug-related treatment-emergent adverse events that led to premature drug discontinuation. There were no clinically relevant changes from baseline to week 96 in fasting lipid parameters, and the median change in body weight at week 96 was 0.0 kg (IQR -2.3, 2.0). Median self-reported adherence was 100% (IQR 100-100%). CONCLUSIONS: Switching to B/F/TAF is an effective long-term option for virologically suppressed adults ≥65 years of age, with favourable safety and tolerability profiles in this population.

Efficacy and safety of switching to bictegravir, emtricitabine, and tenofovir alafenamide in virologically suppressed Asian adults living with HIV: A pooled analysis from three international phase III randomized trials.

OBJECTIVES: Data on switching to bictegravir, emtricitabine, and tenofovir alafenamide (B/F/TAF) in virologically suppressed Asian people living with HIV are limited. We performed a pooled analysis of virologically suppressed Asian participants from three international phase III trials to evaluate the efficacy and safety of switching to B/F/TAF. METHODS: Virologically suppressed people living with HIV were randomized to switch to B/F/TAF or to stay on baseline regimens. The primary endpoint was the proportion of participants with plasma HIV-1 RNA ≥50 copies/ml at week 48. We analysed the incidence of adverse events (AEs), laboratory abnormalities, and changes in relevant tolerability parameters through 48 weeks. RESULTS: Overall, 136 Asian participants were included. The proportions of participants with plasma HIV-1 RNA ≥50 copies/ml at week 48 were low in both arms (0% for B/F/TAF vs 1.4% for those who stayed on baseline regimens). Those who switched to B/F/TAF had virological suppression rates similar to those who stayed on baseline regimens (100% vs 95.9%, p = 0.2485), with no treatment-emergent resistance. Drug-related AEs occurred in three participants in each arm; none were serious. No participants discontinued the study drug because of AEs, and no deaths were observed. No significant differences were observed between the arms in the median changes in estimated glomerular filtration rate, body weight, and most lipid parameters. Switching from tenofovir disoproxil fumarate-containing regimens to B/F/TAF resulted in a significant decrease in tubular proteinuria compared with those who stayed on baseline regimens (p < 0.01). CONCLUSIONS: Virologically suppressed Asian people living with HIV who switched to B/F/TAF maintained 100% virological suppression at week 48, with no treatment-emergent drug resistance and safety profiles comparable to those seen in people who stayed on baseline regimens. CLINICAL TRIAL NUMBER: ClinicalTrials.gov (NCT02603120, NCT02652624, and NCT02603107).

Efficacy, durability, and tolerability of bictegravir/emtricitabine/tenofovir alafenamide for the treatment of HIV in a real-world setting in Belgium.

OBJECTIVES: Our objective was to evaluate the efficacy, durability, and tolerability of bictegravir/emtricitabine/tenofovir alafenamide (BIC/FTC/TAF) in a real-world setting in Belgium. METHODS: This was a retrospective, multicentre cohort study involving adult treatment-naïve (TN) and treatment-experienced (TE) people living with HIV receiving BIC/FTC/TAF between 1 January 2019 and 30 September 2020. The primary outcome was rate of virological suppression (plasma HIV-1 viral load <50 copies/mL; on-treatment analysis) at weeks 24 and 48. The main secondary outcomes included loss of virological suppression (LVS; two consecutive viral loads of >200 copies/mL after being virologically suppressed) by week 48 and analysis of resistance-associated mutations at time of LVS; tolerability of BIC/FTC/TAF over the 48-week study period; and change in weight and proportion of participants reporting a >10% weight gain at week 48. RESULTS: Overall, 2001 participants were included. Through 48 weeks, overall rate of virological suppression was 93.5%, with similar results observed in the following subgroups: age ≥50 years (92.7%), women (92.8%), Black sub-Saharan African (91%), TN (94%), TE (93.2%), and non-suppressed at baseline (86.6%). LVS was observed in 0.7% (n = 14) of participants, with one participant developing resistance-associated mutations to nucleoside reverse transcriptase inhibitors (184 V) and integrase strand transfer inhibitors (263KR). Of the 131 (6.5%) treatment discontinuations, the most common reason was an adverse event (2.4%), with the most frequent being central nervous system/psychiatric (0.4%) and gastrointestinal (0.4%) toxicity. Median weight gain at week 48 was 2 kg (interquartile range -1 to 5), and a >10% weight increase was observed in 11.6% of participants. CONCLUSION: In this large real-world cohort, BIC/FTC/TAF showed excellent virological efficacy in a diverse population of patients with HIV. Rare occurrence of emergent drug resistance was observed, and treatment was well tolerated.

Treatment-emergent reverse transcriptase resistance during antiretroviral therapy with bictegravir, tenofovir alafenamide, and emtricitabine: A case series.

OBJECTIVES: Bictegravir/tenofovir alafenamide/emtricitabine (BIC/TAF/FTC) is a complete regimen for the treatment of HIV with a high barrier to resistance and few reported cases of treatment failure. We present three cases of treatment-emergent resistance to nucleoside/nucleotide reverse transcriptase inhibitors (NRTIs) in patients with suboptimal treatment adherence and assess whether the resistance-associated mutations were present before BIC/TAF/FTC initiation or emerged during therapy. METHODS: We used genotypic drug resistance testing by Sanger sequencing to identify emergent resistance mutations in plasma viral load specimens collected after combination antiretroviral therapy initiation in all participants. Additionally, we performed ultra-deep sequencing by Illumina MiSeq on the earliest available plasma HIV-1 viral load specimen and on any available specimens closest in time to the initiation of BIC/TAF/FTC therapy to identify low-abundance resistance mutations present in the viral quasispecies. RESULTS: All three participants developed NRTI resistance after prolonged exposure and incomplete adherence to BIC/TAF/FTC. The T69N, K70E, M184I, and/or T215I mutations identified in clinical samples at the time of virological failure were not present on deep sequencing of either baseline samples or samples collected before BIC/TAF/FTC initiation. CONCLUSIONS: Despite a generally high genetic barrier to resistance, NRTI resistance-associated mutations may emerge during therapy with BIC/TAF/FTC in the setting of suboptimal adherence.

LC-QQQ-MS based intracellular quantification of bictegravir in peripheral blood mononuclear cells and plasma.

Most antiretrovirals (ARVs) have intracellular therapeutic target sites and therefore, their plasma concentration may be misleading when relating to their efficacy or toxicity. A bioanalytical method for quantification of the ARV drug bictegravir (BTG) in its target site peripheral blood mononuclear cells (PBMCs) is not available till date. This is the first time to establish a sufficiently sensitive mass spectrometry-based bioanalytical method to quantify BTG in both rat PBMCs and plasma. The developed method was validated over the range of 1 ng/ml to 100 ng/ml and 0.005 ng-10ng/sample for plasma and PBMCs, respectively. For PBMCs, average accuracy and precision at four quality control levels were found to be 93.30%-110.00% and 6.52%-8.25%, respectively. Plasma and intracellular pharmacokinetics of BTG was evaluated by the developed method in rats and a lack of accumulation of BTG in the PBMCs was observed. Pearson correlation coefficient data analysis indicated a moderated correlation between plasma and PBMC concentration of BTG. Therefore, it will be beneficial to include a quantification plan for BTG in its actual therapeutic target site during all its future research and development work. This reported method can be useful for site-specific monitoring of BTG in research laboratories and pharmaceutical industries.

A possible case of bictegravir-associated severe unconjugated hyperbilirubinemia.

BACKGROUND: Bictegravir (BIC) co-formulated with emtricitabine (FTC) and tenofovir alafenamide (TAF) is approved by Federal Food and Drug Administration in 2018 for both treatment-naïve and experienced persons living with HIV (PLWH). CASE PRESENTATION: A young man with recently diagnosed human immunodeficiency virus (HIV) infection presented with jaundice. Blood work was significant for mild anemia and grade 4 unconjugated hyperbilirubinemia. A comprehensive evaluation for hemolytic anemia failed to reveal any etiology. Other causes of hyperbilirubinemia were negative. Four months prior, patient was started on antiretroviral therapy with a single tablet regimen containing bictegravir/emtricitabine/tenofovir alafenamide (BIC/FTC/TAF), brand name Biktarvy®, and the medication was suspected to be the cause. The medication was held, and the hyperbilirubinemia improved. CONCLUSION: Severe hyperbilirubinemia can be found in the patient using BIC/FTC/TAF. The data for this adverse reaction is scarce, and more studies are needed on this possible side effect. The mechanism of unconjugated hyperbilirubinemia by INSTI remains undefined.

An indirect comparison of 144-week efficacy, safety, and tolerability of dolutegravir plus lamivudine and second-generation integrase inhibitor-based, 3-drug, single-tablet regimens in therapy-naive people with HIV-1.

BACKGROUND: The long-term efficacy and safety of the 2-drug regimen dolutegravir (DTG) + lamivudine (3TC) and 3-drug single-tablet regimens recommended for antiretroviral therapy (ART)-naive people with HIV-1 (PWH) have yet to be compared directly in clinical trials. This indirect treatment comparison (ITC) was conducted to compare the durability of efficacy and long-term safety of DTG + 3TC vs second-generation, integrase strand transfer inhibitor (INSTI)-based, 3-drug, single-tablet regimens bictegravir/emtricitabine/tenofovir alafenamide (BIC/FTC/TAF) and DTG/abacavir/3TC (DTG/ABC/3TC) at Week 144 after treatment initiation. METHODS: A systematic literature review identified 4 trials evaluating the treatment regimens of interest in ART-naive PWH (GEMINI-1, GEMINI-2, GS-US-380-1489, and GS-US-380-1490). Safety, efficacy, and tolerability results were compared using fixed-effects Bucher ITC methodology to calculate relative outcomes. RESULTS: Rates of virologic suppression (HIV-1 RNA < 50 copies/mL, US Food and Drug Administration Snapshot analysis) and virologic failure (HIV-1 RNA ≥ 50 copies/mL) as well as mean change in CD4 + cell count were similar with DTG + 3TC, BIC/FTC/TAF, and DTG/ABC/3TC at Week 144. Serious adverse events occurred less frequently with DTG + 3TC compared with both BIC/FTC/TAF (odds ratio [OR], 0.51; 95% CI 0.29-0.87; P = 0.014) and DTG/ABC/3TC (OR, 0.38; 95% CI 0.19-0.75; P = 0.006). Discontinuations and overall adverse events were similar across all 3 regimens. CONCLUSIONS: These results suggest that the 2-drug regimen DTG + 3TC offers comparable and durable efficacy with fewer serious adverse events vs BIC/FTC/TAF and DTG/ABC/3TC through 144 weeks of treatment in ART-naive PWH. These long-term comparative data support the therapeutic value of DTG + 3TC for PWH.

Increased human immunodeficiency virus viral load with cerebral infarction due to varicella zoster virus vasculopathy on treatment with bictegravir/emtricitabine/tenofovir alafenamide suspension: a case report and literature review.

BACKGROUND: Varicella-Zoster virus (VZV) vasculopathy occasionally occurs in immunocompromised patients and is difficult to treat. The risk factor and optimal therapy remain unclear. Patients with human immunodeficiency virus (HIV) and dysphagia or difficulty in oral intake receive antiretroviral therapy (ART) suspension. However, there remains little evidence regarding ART suspension. CASE PRESENTATION: We experienced a case of a 55-year-old man diagnosed with HIV and severe multiple cerebral infarctions due to VZV vasculopathy. We started on bictegravir/tenofovir alafenamide/emtricitabine (BIC/TAF/FTC) and acyclovir (ACV), and prednisone. He was started on BIC/TAF/FTC suspension because of deteriorated swallowing. The HIV viral load was increased; however, no drug-resistance genes were detected. We successfully treated him with doltegravir/abacavir/lamibudine suspension. We performed two literature reviews of the administration of BIC/TAF/3TC suspension and VZV vasculopathy in patients with HIV. Three cases of BIC/TAF/3TC suspension were considered treatment failures. Recent history of VZV infection and a CD4 count under 200 µL may be risk factors for VZV vasculopathy. The effective treatment may be using steroid and ACV; however, treatment duration could differ. CONCLUSIONS: BIC/TAF/FTC suspension administration may be unstable, and treating ACV and steroid may be optimal therapy for VZV vasculopathy; however, the evidence level is low.

A green approach for the analysis of emtricitabine bictegravir and tenofovir in a pharmaceutical preparation using novel HPLC and spectrophotometric methods.

Two spectrophotometric techniques and a novel HPLC method were consecutively applied for the simultaneous quantification of the active ingredients of emtricitabine (EMC), tenofovir (TNF), and bictegravir (BIC). The first spectrophotometric method is the dual amplitude difference method coupled with the ratio difference method. TNF was determined using the dual amplitude difference method, while BIC and EMC were determined using the ratio difference method. The second spectrophotometric method was the constant multiplication with absorbance extraction method, and was applied for the determination of active substances used in the treatment of human immunodeficiency virus (HIV) infection. BIC was determined by the constant multiplication method, whereas EMC and TNF were determined using the absorbance extraction method. For the HPLC method, the XBridge C18 column was used. The solvent system comprised acetonitrile:phosphate buffer (pH 6.8; 30:70 v/v). All active ingredients were detected at 260.0 nm, and the flow rate was 0.5 mL/min. The experiment was completed within 5.5 min. The experiments carried out enabled the simultaneous analysis of the three active substances and they were economical, fast, environmentally friendly, and simple. The methods have been successfully applied to prepare mixtures and tablets without matrix interference. The methods were evaluated in terms of green chemistry. The methods have been validated according to International Council for Harmonisation (ICH) guidelines.

A clinical review of HIV integrase strand transfer inhibitors (INSTIs) for the prevention and treatment of HIV-1 infection.

Integrase strand transfer inhibitors (INSTIs) have improved the treatment of human immunodeficiency virus (HIV). There are currently four approved for use in treatment-naïve individuals living with HIV; these include first generation raltegravir, elvitegravir, and second generation dolutegravir and bictegravir. The most recent INSTI, cabotegravir, is approved for (1) treatment of HIV infection in adults to replace current antiretroviral therapy in individuals who maintain virologic suppression on a stable antiretroviral regimen without history of treatment failure and no known resistance to its components and (2) pre-exposure prophylaxis in individuals at risk of acquiring HIV-1 infection. Cabotegravir can be administered intramuscularly as a monthly or bi-monthly injection depending on the indication. This long-acting combination has been associated with treatment satisfaction in clinical studies and may be helpful for individuals who have difficulty taking daily oral medications. Worldwide, second generation INSTIs are preferred for treatment-naïve individuals. Advantages of these INSTIs include their high genetic barrier to resistance, limited drug-drug interactions, excellent rates of virologic suppression, and favorable tolerability. Few INSTI resistance-associated mutations have been reported in clinical trials involving dolutegravir, bictegravir and cabotegravir. Other advantages of specific INSTIs include their use in various populations such as infants and children, acute HIV infection, and individuals of childbearing potential. The most common adverse events observed in clinical studies involving INSTIs included diarrhea, nausea, insomnia, fatigue, and headache, with very low rates of treatment discontinuation versus comparator groups. The long-term clinical implications of weight gain associated with second generation INSTIs dolutegravir and bictegravir warrants further study. This review summarizes key clinical considerations of INSTIs in terms of clinical pharmacology, drug-drug interactions, resistance, and provides perspective on clinical decision-making. Additionally, we summarize major clinical trials evaluating the efficacy and safety of INSTIs in treatment-naïve patients living with HIV as well as individuals at risk of acquiring HIV infection.

Forgiveness of INSTI-Containing Regimens at Drug Concentrations Simulating Variable Adherence In Vitro.

The integrase strand transfer inhibitor (INSTI)-based regimens bictegravir/emtricitabine/tenofovir alafenamide (BIC/FTC/TAF), dolutegravir (DTG)+FTC/TAF, DTG/lamivudine (3TC), and DTG/rilpivirine (RPV) are all approved for treatment of HIV-infected patients, with various limitations. Here, time to in vitro viral breakthrough (VB) and resistance barrier using simulated human drug exposures at either full or suboptimal treatment adherence to each regimen were compared. At drug concentrations corresponding to full adherence and 1 missed dose (Cmin and Cmin-1), no VB occurred with any regimen. At Cmin-2, VB occurred only with DTG+3TC, with emergent resistance to both drugs. At Cmin-3, VB occurred with all regimens: 100% of DTG+3TC cultures had VB by day 12, and <15% of BIC+FTC+TAF, DTG+FTC+TAF, and DTG+RPV cultures had VB. Emergent reverse transcriptase (RT) or integrase (IN) resistance was seen with DTG+RPV and DTG+3TC but not with BIC+FTC+TAF or DTG+FTC+TAF. At Cmin-4, 100% VB occurred with DTG+3TC and DTG+FTC+TAF by day 12, while 94% VB occurred with DTG+RPV by day 25 and only 50% VB occurred with BIC+FTC+TAF by day 35. Emergent Cmin-4 drug resistance was seen with all regimens but at differing frequencies; DTG+RPV had the most cultures with resistance. Emergent resistance was consistent with clinical observations. Overall, under high adherence conditions, no in vitro VB or resistance development occurred with these INSTI-based regimens. However, when multiple missed doses were simulated in vitro, BIC+FTC+TAF had the highest forgiveness and barrier to resistance of all tested regimens. Compared to DTG+3TC and DTG+FTC+TAF, DTG+RPV had higher forgiveness but lower resistance barrier after several simulated missed doses.

Human and nonclinical disposition of [14C]bictegravir, a potent integrase strand-transfer inhibitor for the treatment of HIV-1 infection.

Bictegravir (BIC) is a potent small-molecule integrase strand-transfer inhibitor (INSTI) and a component of Biktarvy®, a single-tablet combination regimen that is currently approved for the treatment of human immunodeficiency virus type 1 (HIV-1) infection. The absorption, metabolism, distribution, and elimination (ADME) characteristics of BIC were determined through in vivo nonclinical and clinical studies (IND 121318).[14C]BIC was rapidly absorbed orally in mice, rats, monkeys and human. The cumulative dose recovery was high in nonclinical species (>80%) and humans (95.3%), with most of the excreted dose recovered in faeces. Quantifiable radioactivity with declining concentration was observed in rat tissues suggesting reversible binding. Unchanged BIC was the most abundant circulating component in all species along with two notable metabolites M20 (a sulphate conjugate of hydroxylated BIC) and M15 (a glucuronide conjugate of BIC). BIC was primarily eliminated by hepatic metabolism followed by excretion of the biotransformed products into faeces. In vitro drug-drug interaction (DDI) studies with M15 and M20 demonstrated that no clinically relevant interactions were expected.Overall, BIC is a novel and potent INSTI with a favourable resistance, PK, and ADME profile that provides important improvements over other currently available INSTIs for the treatment of HIV-1.

Human pharmacokinetics prediction with an in vitro-in vivo correction factor approach and in vitro drug-drug interaction profile of bictegravir, a potent integrase-strand transfer inhibitor component in approved biktarvy® for the treatment of HIV-1 infection.

Bictegravir (BIC) is a potent small-molecule integrase strand-transfer inhibitor (INSTI) and a component of Biktarvy®, a single-tablet combination regimen that is currently approved for the treatment of human immunodeficiency virus type 1 (HIV-1) infection. The in vitro properties, pharmacokinetics (PK), and drug-drug interaction (DDI) profile of BIC were characterised in vitro and in vivo.BIC is a weakly acidic, ionisable, lipophilic, highly plasma protein-bound BCS class 2 molecule, which makes it difficult to predict human PK using standard methods. Its systemic plasma clearance is low, and the volume of distribution is approximately the volume of extracellular water in nonclinical species. BIC metabolism is predominantly mediated by cytochrome P450 enzyme (CYP) 3A and UDP-glucuronosyltransferase 1A1. BIC shows a low potential to perpetrate clinically meaningful DDIs via known drug metabolising enzymes or transporters.The human PK of BIC was predicted using a combination of bioavailability and volume of distribution scaled from nonclinical species and a modified in vitro-in vivo correlation (IVIVC) correction for clearance. Phase 1 studies in healthy subjects largely bore out the prediction and supported the methods used. The approach presented herein could be useful for other drug molecules where standard projections are not sufficiently accurate. .