Weight change with antiretroviral switch from integrase inhibitor or tenofovir alafenamide-based to Doravirine-Based regimens in people with HIV.

BACKGROUND: Weight gain has been well-described with integrase strand transfer inhibitors (INSTIs) and tenofovir alafenamide (TAF). Doravirine (DOR) has been identified as a relatively "weight-neutral" drug; however, there is little data describing its effect on weight change in routine clinical practice. METHODS: We conducted a retrospective chart review of weight change among people with HIV changing from an INSTI- to a non-INSTI regimen with DOR. RESULTS: At the time of ART switch, among 49 people with HIV, the mean age was 47 years, 24% were female, and 75% had HIV-1 viral load <200 copies/mL. Most (55%) people with HIV were taking bictegravir/TAF/emtricitabine prior to the switch. Although 84% switched due to concerns about weight gain, only 16% had a weight gain of ≥10% in the year preceding, and 49% had no substantial change in weight. 86% switched to DOR/lamivudine/tenofovir disoproxil fumarate. A weight decrease (-2.6% [95% CI: -5.1, -0.1%, p = .041] was seen over the year following the ART switch. Weight change prior to switch was greatest in the year 2021 compared to 2019, 2020, and 2022. CONCLUSIONS: Overall, modest changes in weight were seen following ART switch from INSTI-based regimen to a DOR-based, non-INSTI regimen. Further investigations with larger people with HIV cohorts will be helpful to guide clinical practice, while the impact of the COVID-19 pandemic on weight change should also be considered.

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 ).

Assessment of swallowability and acceptability of scored darunavir/cobicistat/emtricitabine/tenofovir alafenamide (D/C/F/TAF) fixed-dose combination (FDC) tablets in HIV-1-infected children aged ≥6 to <12 years, using matching placebo tablets: A randomized study.

BACKGROUND: Darunavir/cobicistat/emtricitabine/tenofovir alafenamide (D/C/F/TAF) fixed-dose combination (FDC) was developed as a once-daily, complete antiretroviral (ARV) regimen therapy to address the need for simplified protease inhibitor-based ARV regimens. This study assessed the swallowability and acceptability for long-term use of scored placebo tablets matching the D/C/F/TAF FDC tablets in children living with HIV-1. METHODS: This study (NCT04006704) was a Phase 1, open-label, randomized, single-dose, 2-period, 2-sequence crossover study in children living with HIV-1, aged ≥6 to <12 years and weighing ≥25 to <40 kg, on a stable ARV regimen for ≥3 months. Participants were asked to swallow whole (size, 21 × 11 × 7 mm) and split matching placebo D/C/F/TAF tablets. Swallowability of the matching placebo D/C/F/TAF tablets (primary endpoint) was assessed by observers. Acceptability of taking matching placebo D/C/F/TAF tablets and current ARVs was evaluated by participants using a 3-point questionnaire. Participants rated the acceptability for long-term daily use of the placebo D/C/F/TAF tablets, and observers assessed how easily caregivers could split a scored tablet by hand, using 3-point questionnaires. RESULTS: Among the 24 participants who enrolled and completed the study, 95.8% (23/24) were able to swallow the whole and split matching placebo D/C/F/TAF tablets after 1 or 2 attempts. Most participants (>70%) rated the acceptability of tablets for long-term daily use as acceptable or good to take. Breaking the tablets was considered easy or OK by 79.2% (19/24) of caregivers. CONCLUSION: Scored D/C/F/TAF FDC tablets are swallowable - with whole favoured over split - and considered at least acceptable for long-term daily intake in children living with HIV-1 aged ≥6 to <12 years. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04006704.

Therapeutic effectiveness analysis of tenofovir alafenamide and tenofovir disoproxil fumarate on the treatment for chronic hepatitis B.

To explore the therapeutic effectiveness of tenofovir alafenamide (TAF) and tenofovir disoproxil fumarate (TDF) on the treatment for chronic hepatitis B (CHB). Retrospectively analyzing 241 cases of chronic hepatitis B patients admitted to our hospital from January 2020 to December 2021, they were divided into a TAF group of 180 cases and a TDF group of 61 cases. The liver function, serum virus markers, clinical efficacy, adverse reactions and cost-effectiveness ratio (CER) analysis of 2 groups were compared. Two groups of patients had no statistically significant difference in the levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST) and total bilirubin (TBIL) before treatment. After treatment, the levels of ALT, AST and TBIL were lower than before treatment in both groups (P < .05), but the inter-group difference was not statistically significant (P > .05). After treatment, Hepatitis B surface antigen (HBsAg) conversion rate and Hepatitis B virus DNA (HBV-DNA) conversion rate in the 2 groups had no statistically significant difference. After treatment, the difference in total clinical cure rate between the 2 groups has no statistical significance (P > .05), adverse reactions rate of TAF group was lower than that of TDF group (P < .05). The drug cost median of TAF group was higher than that of TDF (P < .05), but Cost-effectiveness analysis showed the CER of TAF group was similar of TDF group. TAF or TDF therapy can both improve liver function and promote recovery in patients with CHB, achieving the goal of treatment. TAF have more cost but have similar CER to TDF. Moreover, TAF therapy has a higher safety profile.

Evaluation of Pharmacokinetics of a BCS Class III Drug with Two Different Study Designs: Tenofovir Alafenamide Monofumarate Film-coated Tablet.

Tenofovir alafenamide (TAF) is a BCS Class III compound and an oral pro-drug of Tenofovir (TFV) with limited oral bioavailability. The bioavailability of the oral intake increases with food as a result of the low stability of the active substance in the stomach. The reference drug is "Vemlidy® 25 mg Film Tablet", which contains 25 mg of TAF in "hemifumarate" form, is under patent protection until 15.08.2032 by Gilead, and so the "monofumarate" form was used in the present study. At first, a pilot study was conducted involving 12 subjects under fed conditions. The results of the pilot study revealed the test and reference products were not bioequivalent, as a result of insufficient statistical power and high inter-subject variability. Secondly, a physiologically based pharmacokinetic (PBPK) simulation was performed based on the pilot study results and literature data. Finally, the power of the design was increased and the pivotal study design was optimized into a four-period, full-replicated, cross-over study with 34 subjects under fed conditions and it was concluded that the test and reference products were bioequivalent. In conclusion, the present study proved the importance of a correct study design with higher statistical power for a BCS Class III compound with high variability, to present the pharmacokinetics.

Switch to fixed-dose doravirine (100 mg) with islatravir (0·75 mg) once daily in virologically suppressed adults with HIV-1 on bictegravir, emtricitabine, and tenofovir alafenamide: 48-week results of a phase 3, randomised, controlled, double-blind, non-inferiority trial.

BACKGROUND: Doravirine and islatravir is an investigational, once-daily regimen with high antiviral potency, favourable safety and tolerability, and a low propensity for resistance. We investigated a switch from bictegravir, emtricitabine, and tenofovir alafenamide to doravirine (100 mg) and islatravir (0·75 mg) in virologically suppressed adults with HIV-1. METHODS: We conducted a phase 3, multicentre, randomised, active-controlled, double-blind, double-dummy, non-inferiority trial at 89 research, community, and hospital-based clinics in 11 countries. Adults aged 18 years or older with fewer than 50 HIV-1 RNA copies per mL for at least 3 months on bictegravir (50 mg), emtricitabine (200 mg), and tenofovir alafenamide (25 mg) and no history of previous virological failure on any past or current regimen were randomly assigned (1:1) by a computer-generated randomisation allocation schedule, with block randomisation based on a block size of four, to switch to doravirine (100 mg) and islatravir (0·75 mg) or continue bictegravir, emtricitabine, and tenofovir alafenamide orally once daily, with matching placebos taken by all participants. Participants, investigators, study staff, and sponsor personnel involved in study drug administration or clinical evaluation of participants were masked to treatment assignment until week 48. Participants were instructed at each visit to take one tablet from each of the two bottles received, one of study drug and one of placebo, once daily, and participants were assessed at baseline and weeks 4, 12, 24, 36, and 48. The primary endpoint was the proportion of participants with greater than or equal to 50 HIV-1 RNA copies per mL at week 48 in the full analysis set (ie, all participants who received at least one dose of study drug; US Food and Drug Administration snapshot; prespecified non-inferiority margin 4%). The study is ongoing, with all remaining participants in post-treatment follow-up, and is registered with ClinicalTrials.gov, NCT04223791. FINDINGS: We screened 726 individuals for eligibility between Feb 18 and Sept 3, 2020, of whom 643 (88·6%) participants were randomly assigned to a treatment group (183 [28·5%] women and 460 [71·5%] men). 322 participants were switched to doravirine (100 mg) and islatravir (0·75 mg) and 321 continued bictegravir, emtricitabine, and tenofovir alafenamide (two participants [one with a protocol deviation and one who withdrew] assigned to bictegravir, emtricitabine, and tenofovir alafenamide did not receive treatment). The last follow-up visit for the week 48 analysis occurred on Aug 26, 2021. At week 48, two (0·6%) of 322 participants in the doravirine and islatravir group compared with one (0·3%) of 319 participants in the bictegravir, emtricitabine, and tenofovir alafenamide group had greater than or equal to 50 HIV-1 RNA copies per mL (difference 0·3%, 95% CI -1·2 to 2·0). The per-protocol analysis showed consistent results. 25 (7·8%) participants in the doravirine and islatravir group had headache compared with 23 [7·2%] participants in the bictegravir, emtricitabine, and tenofovir alafenamide group; 101 (31·4%) compared with 98 (30·7%) had infections; and eight (2·5%) participants in each group discontinued therapy due to adverse events. 32 (9·9%) participants had treatment-related adverse events in the islatravir and doravirine group comapred with 38 (11·9%) in the bictegravir, emtricitabine, and tenofovir alafenamide group. In the islatravir and doravirine group, CD4 cell counts (mean change -19·7 cells per µL) and total lymphocyte counts (mean change -0·20 × 109/L) were decreased at 48 weeks. INTERPRETATION: Switching to daily doravirine (100 mg) and islatravir (0·75 mg) was non-inferior to bictegravir, emtricitabine, and tenofovir alafenamide at week 48. However, decreases in CD4 cell and total lymphocyte counts do not support the further development of once-daily doravirine (100 mg) and islatravir (0·75 mg). FUNDING: Merck Sharp & Dohme, a subsidiary of Merck & Co.

Effects of Antiretroviral Treatment on Central and Peripheral Immune Response in Mice with EcoHIV Infection.

HIV infection is an ongoing global health issue, despite increased access to antiretroviral therapy (ART). People living with HIV (PLWH) who are virally suppressed through ART still experience negative health outcomes, including neurocognitive impairment. It is increasingly evident that ART may act independently or in combination with HIV infection to alter the immune state, though this is difficult to disentangle in the clinical population. Thus, these experiments used multiplexed chemokine/cytokine arrays to assess peripheral (plasma) and brain (nucleus accumbens; NAc) expression of immune targets in the presence and absence of ART treatment in the EcoHIV mouse model. The findings identify the effects of EcoHIV infection and of treatment with bictegravir (B), emtricitabine (F), and tenofovir alafenamide (TAF) on the expression of numerous immune targets. In the NAc, this included EcoHIV-induced increases in IL-1α and IL-13 expression and B/F/TAF-induced reductions in KC/CXCL1. In the periphery, EcoHIV suppressed IL-6 and LIF expression, while B/F/TAF reduced IL-12p40 expression. In the absence of ART, IBA-1 expression was negatively correlated with CX3CL1 expression in the NAc of EcoHIV-infected mice. These findings identify distinct effects of ART and EcoHIV infection on peripheral and central immune factors and emphasize the need to consider ART effects on neural and immune outcomes.

Pharmacokinetics of tenofovir alafenamide, emtricitabine, and dolutegravir in a patient on peritoneal dialysis.

INTRODUCTION: Peritoneal dialysis (PD) is an effective renal replacement modality in people with HIV (PWH) with end-stage kidney disease (ESKD), particularly those with residual kidney function. Data on pharmacokinetics (PK) of antiretrovirals in patients on peritoneal dialysis are limited. METHODS: A single-participant study was performed on a 49-year-old gentleman with ESKD on PD and controlled HIV on once daily dolutegravir (DTG) 50 mg + tenofovir alafenamide (TAF) 25 mg / emtricitabine (FTC) 200 mg. He underwent serial blood plasma, peripheral blood mononuclear cell, and urine PK measurements over 24 h after an observed DTG + FTC/TAF dose. RESULTS: Plasma trough (Cmin) concentrations of TAF, tenofovir (TFV), FTC, and DTG were 0.05, 164, 1,006, and 718 ng/mL, respectively. Intracellular trough concentrations of TFV-DP and FTC-TP were 1142 and 11,201 fmol/million cells, respectively. Compared to published mean trough concentrations in PWH with normal kidney function, observed TFV and FTC trough concentrations were 15.5- and 20-fold higher, while intracellular trough concentrations of TFV-DP and FTC-TP were 2.2-fold and 5.4-fold higher, respectively. TFV and FTC urine levels were 20 times lower than in people with normal GFR. CONCLUSIONS: In a single ESKD PWH on PD, daily TAF was associated with plasma TFV and intracellular TFV-DP trough concentrations 15-fold and 2-fold higher than those of people with uncompromised kidney function, potentially contributing to nephrotoxicity. This suggests that TFV accumulates on PD; thus, daily TAF in PD patients may require dose adjustment or regimen change to optimize treatment, minimize toxicity, and preserve residual kidney function.

Twelve-month effectiveness and safety of bictegravir/emtricitabine/tenofovir alafenamide in people with HIV from the Canadian cohort of the observational BICSTaR study.

The BICSTaR (BICtegravir Single Tablet Regimen) study is investigating the effectiveness and safety of bictegravir/emtricitabine/tenofovir alafenamide (B/F/TAF) in people with human immunodeficiency virus (HIV) treated in routine clinical practice. BICSTaR is an ongoing, prospective, observational cohort study across 14 countries. Treatment-naïve (TN) and treatment-experienced (TE) people with HIV (≥18 years of age) are being followed for 24 months. We present an analysis of the primary endpoint (HIV-1 RNA < 50 copies/mL; missing-equals-excluded [M = E]) at month 12 in the BICSTaR Canada cohort, including secondary (CD4 count, CD4/CD8 ratio, safety/tolerability) and exploratory (persistence, treatment satisfaction) endpoints. In total, 201 participants were enrolled in the BICSTaR Canada cohort. The analysis population included 170 participants (TN, n = 10; TE, n = 160), with data collected between November 2018 and September 2020. Of the participants, 88% were male, 72% were White, and 90% had ≥ 1 comorbid condition(s). Median (quartile [Q]1-Q3) age was 50 (39-58) years and baseline CD4 count was 391.5 (109.0-581.0) cells/µL in TN participants and 586.0 (400.0-747.0) cells/µL in TE participants. After 12 months of B/F/TAF treatment, HIV-1 RNA was < 50 copies/mL in 100% (9/9) of TN-active participants and 97% (140/145) of TE-active participants (M = E analysis). Median (Q1-Q3) CD4 cell count increased by +195 (125-307) cells/µL in TN participants and by + 30 (-50 to 123) cells/µL in TE participants. Persistence on B/F/TAF was high through month 12 with 10% (1/10) of TN and 7 % (11/160) of TE participants discontinuing B/F/TAF within 12 months of initiation of treatment. No resistance to B/F/TAF emerged. Study drug-related adverse events occurred in 7% (12/169) of participants, leading to B/F/TAF discontinuation in 4 of 169 participants. Improvements in treatment satisfaction were observed in TE participants. B/F/TAF demonstrated high levels of effectiveness, persistence, and treatment satisfaction, and was well tolerated through month 12 in people with HIV treated in routine clinical practice in Canada.

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.

Associations between change in BMI and the risk of hypertension and dyslipidaemia in people receiving integrase strand-transfer inhibitors, tenofovir alafenamide, or both compared with other contemporary antiretroviral regimens: a multicentre, prospective observational study from the RESPOND consortium cohorts.

BACKGROUND: Integrase strand-transfer inhibitors (INSTIs) and tenofovir alafenamide have been associated with weight gain in several clinical trials and observational cohorts. However, whether weight gain associated with INSTIs and tenofovir alafenamide confers a higher risk of weight-related clinical events is unclear. We aimed to assess whether changes in BMI differentially increase hypertension or dyslipidaemia risk in people with HIV receiving INSTIs, tenofovir alafenamide, or both versus other contemporary regimens. METHODS: This multicentre, prospective observational study analysed prospective data from RESPOND, an international consortium of HIV cohorts for which recruitment began in 2017 and is still ongoing from HIV clinics and hospitals in 37 European countries and Australia. Participants were eligible if they were aged 18 years or older, receiving INSTI-containing antiretroviral therapy (ART) regimens or a contemporary non-INSTI, did not have hypertension or dyslipidaemia at baseline, and had baseline and at least two follow-up BMI, lipid, and blood pressure measurements. We excluded participants without baseline CD4 or HIV RNA results and those receiving non-ART medications associated with weight changes, including antipsychotics and mood stabilisers, corticosteroids, insulin, and insulin secretagogues. They were followed up from baseline until the earliest hypertension or dyslipidaemia event, their last visit, or Dec 31, 2021, whichever was earlier. The primary outcomes were incidence of hypertension and dyslipidaemia, for which we used multivariable Poisson regression adjusted for time-updated BMI to determine unadjusted and adjusted incidence rate ratios (IRRs) of hypertension and dyslipidaemia in people receiving INSTIs, tenofovir alafenamide, or both, and tested for interaction between time-updated ART regimen and BMI. FINDINGS: Of the 35 941 RESPOND participants, 9704 (7327 [75·5 %] male and 2377 [24·5%] female) were included in the hypertension analysis and 5231 (3796 [72·6%] male and 1435 [27·4%] female) were included in the dyslipidaemia analysis. In the univariable model, hypertension was more common in individuals receiving an INSTI with tenofovir alafenamide (IRR 1·70, 95% CI 1·54-1·88) or an INSTI without tenofovir alafenamide (1·41, 1·30-1·53) compared with those receiving neither INSTIs nor tenofovir alafenamide. Adjustment for time-updated BMI and confounders attenuated risk in participants receiving an INSTI with (IRR 1·48, 1·31-1·68) or without (1·25, 1·13-1·39) tenofovir alafenamide. Similarly, dyslipidaemia was more common in participants using tenofovir alafenamide with an INSTI (IRR 1·24, 1·10-1·40) and tenofovir alafenamide alone (1·22, 1·03-1·44) than in participants using neither INSTI nor tenofovir alafenamide. Adjustment for BMI and confounders attenuated the risk in participants receiving tenofovir alafenamide with an INSTI (adjusted IRR 1·21, 1·07-1·37), whereas the risk in those receiving tenofovir alafenamide alone became non-significant (1·15, 0·96-1·38). The associations between increasing BMI and risk of hypertension and dyslipidaemia did not differ between participants receiving different ART regimens (pinteraction=0·46 for hypertension; pinteraction=0·31 for dyslipidaemia). INTERPRETATION: Although residual confounding cannot be entirely excluded, the use of INSTIs was associated with incident hypertension, and the use of tenofovir alafenamide was associated with dyslipidaemia, with the latter association partly mediated by weight gain. These results reiterate the need for hypertension and dyslipidaemia screening in people with HIV. FUNDING: The CHU St Pierre Brussels HIV Cohort, The Austrian HIV Cohort Study, The Australian HIV Observational Database, The AIDS Therapy Evaluation in the Netherlands national observational HIV cohort, The Brighton HIV Cohort, The National Croatian HIV Cohort, The EuroSIDA cohort, The Frankfurt HIV Cohort Study, The Georgian National AIDS Health Information System, The Nice HIV Cohort, The ICONA Foundation, The Modena HIV Cohort, The PISCIS Cohort Study, The Swiss HIV Cohort Study, The Swedish InfCare HIV Cohort, The Royal Free HIV Cohort Study, The San Raffaele Scientific Institute, The University Hospital Bonn HIV Cohort, The University of Cologne HIV Cohort, Merck Life Sciences, ViiV Healthcare, and Gilead Sciences.

Relative Bioavailability of Dolutegravir (DTG) and Emtricitabine/Tenofovir Alafenamide Fumarate (F/TAF) Administered as Paediatric Tablet Formulations in Healthy Volunteers.

BACKGROUND AND OBJECTIVE: Within the UNIVERSAL project (RIA2019PD-2882) we aim to develop a paediatric dolutegravir (DTG)/emtricitabine (FTC or F)/tenofovir alafenamide (TAF) fixed-dose combination. To inform dosing of this study, we undertook a relative bioavailability (RBA) study in healthy volunteers to investigate a potential pharmacokinetic effect when paediatric formulations of DTG and F/TAF are taken together. METHODS: Participants received all of the following treatments as paediatric formulations in randomised order: a single dose of 180/22.5 mg F/TAF; a single dose of 30 mg DTG; a single dose of 180/22.5 mg F/TAF plus 30 mg DTG. Blood concentrations of DTG, FTC, TAF, and tenofovir (TFV) were measured over 48 h post-dose. If the 90% confidence intervals (CIs) of the geometric least squares mean (GLSM) ratios of area under the curve (AUC) and maximum concentration (Cmax) of each compound were within 0.70-1.43, we considered this as no clinically relevant PK interaction. RESULTS: A total of 15 healthy volunteers were included. We did not observe a clinically relevant PK interaction between the paediatric DTG and F/TAF formulations for the compounds DTG, FTC, and TFV. For TAF, the lower boundaries of the 90% CIs of the GLSM ratios of the AUC0-∞ and Cmax fell outside our acceptance criteria of 0.70-1.43. CONCLUSIONS: Although TAF AUC and Cmax 90% CIs fell outside the pre-defined criteria (0.62-1.11 and 0.65-1.01, respectively), no consistent effect on TAF PK was observed, likely due to high inter-subject variability. Moreover, there are several reasons to rely on TFV exposure as being more clinically relevant than TAF exposure. Therefore, we found no clinically relevant interactions in this study.

Profiling the Interaction between Human Serum Albumin and Clinically Relevant HIV Reverse Transcriptase Inhibitors.

Tenofovir (TFV) is the active form of the prodrugs tenofovir disoproxil fumarate (TDF) and tenofovir alafenamide (TAF), both clinically prescribed as HIV reverse transcriptase inhibitors. The biophysical interactions between these compounds and human serum albumin (HSA), the primary carrier of exogenous compounds in the human bloodstream, have not yet been thoroughly characterized. Thus, the present study reports the interaction profile between HSA and TFV, TDF, and TAF via UV-Vis, steady-state, and time-resolved fluorescence techniques combined with isothermal titration calorimetry (ITC) and in silico calculations. A spontaneous interaction in the ground state, which does not perturb the microenvironment close to the Trp-214 residue, is classified as weak. In the case of HSA/TFV and HSA/TDF, the binding is both enthalpically and entropically driven, while for HSA/TAF, the binding is only entropically dominated. The binding constant (Ka) and thermodynamic parameters obtained via ITC assays agree with those obtained using steady-state fluorescence quenching measurements, reinforcing the reliability of the data. The small internal cavity known as site I is probably the main binding pocket for TFV due to the low steric volume of the drug. In contrast, most external sites (II and III) can better accommodate TAF due to the high steric volume of this prodrug. The cross-docking approach corroborated experimental drug-displacement assays, indicating that the binding affinity of TFV and TAF might be impacted by the presence of different compounds bound to albumin. Overall, the weak binding capacity of albumin to TFV, TDF, and TAF is one of the main factors for the low residence time of these antiretrovirals in the human bloodstream; however, positive cooperativity for TAF and TDF was detected in the presence of some drugs, which might improve their residence time (pharmacokinetic profile).

Long-term outcomes of bictegravir/emtricitabine/tenofovir alafenamide as first-line therapy and as switch strategy in virologically suppressed persons with HIV: data from the ICONA cohort.

OBJECTIVES: To assess the effectiveness of bictegravir/emtricitabine/tenofovir alafenamide (BIC/FTC/TAF) among people poorly represented in clinical trials and potentially at higher risk of suboptimal response to ART. METHODS: Observational cohort study on persons with HIV (PWH) enrolled in ICONA who started BIC/FTC/TAF as initial therapy or as switching regimen while virologically suppressed. Primary endpoint was time to treatment failure (TF): new AIDS/death or virological failure (VF) or discontinuation for toxicity/failure. Secondary endpoints were time to treatment discontinuation for toxicity (TDT) and to VF. Groups of interest were those aged >50 years, female sex, and advanced HIV disease at first ART start. Probability of the events overall and according to groups and adjusted HR for every endpoint were calculated by Kaplan-Meier curves and Cox regression models. RESULTS: Nine hundred and thirty-three ART-naive and 1655 ART-experienced PWH initiated BIC/FTC/TAF. Over a median follow-up of 69.8 weeks, 89 (9.6%) PWH at their first regimen experienced TF. PWH aged >50 years had 1.83-fold (95% CI: 1.19-2.83) higher risk of TF; PWH with advanced HIV disease had 2.21-fold (95% CI: 1.53-3.82) higher risk; there were no differences in TF according to sex.Over a median follow-up of 146.3 weeks, 109 (6.6%) out of 1655 switching PWH experienced TF; no differences were found in the risk of TF, TDT and VF according to groups of interest. CONCLUSIONS: Overall, BIC/FTC/TAF is well tolerated and virologically effective in the real-world scenario for ART-naive and -experienced PWH. Older ART-naive PWH and those with advanced HIV disease may respond less well as the burden of diseases might compromise treatment efficacy.

Integrase strand transfer inhibitor resistance mediated by R263K plus E157Q in a patient with HIV infection treated with bictegravir/tenofovir alafenamide/emtricitabine: case report and review of the literature.

OBJECTIVES: The in vivo selection of E157Q plus R263K has not been reported in patients treated with coformulated bictegravir/emtricitabine/tenofovir alafenamide (BIC/FTC/TAF). To the best of our knowledge, we hereby report the first case of high-grade INSTI resistance associated with the presence of these aminoacidic substitutions in a treatment-experienced HIV patient treated with BIC/FTC/TAF. METHODS: Clinical case report and review of the literature. RESULTS: A heavily treatment-experienced patient was switched to BIC/FTC/TAF due to drug-drug interactions after being diagnosed with disseminated Mycobacterium avium-intracellulare disease. He had been treated before with raltegravir with poor adherence. No mutations in the integrase gene were detected 1 year after finishing treatment with raltegravir. Months after being switched to BIC/FTC/TAF, and again with poor adherence documented, virological failure (VF) was detected. The polymorphic substitution E157Q and the resistance mutation R263K in the integrase gene were detected, as well as M184V, among other mutations in the reverse transcriptase gene. The patient is currently being treated with dolutegravir q12h plus boosted darunavir along with directly observed treatment, and for the first time in 20 years, plasmatic viral load values are below 100 copies/mL. CONCLUSIONS: This case illustrates that the combination of E157Q and R263K plus M184V can be selected in vivo in a clinical scenario of poor adherence with BIC/FTC/TAF, although it is a very rare phenomenon. Previous VF with first-generation integrase strand transfer inhibitors (INSTIs) should be kept in mind when switching patients to second-generation INSTIs.

Bictegravir/emtricitabine/tenofovir alafenamide as first-line treatment in naïve HIV patients in a rapid-initiation model of care: BIC-NOW clinical trial.

OBJECTIVE: Multiple strategies have been utilised to reduce the incidence of HIV, including PrEP and rapid antiretroviral therapy initiation. The study objectives were to evaluate the efficacy, safety, satisfaction, treatment adherence, and system retention obtained with rapid initiation of bictegravir/emtricitabine/tenofovir alafenamide (BIC/FTC/TAF) in naïve patients. METHODS: This phase IV, multicenter, open-label, single-arm, 48-week clinical trial enrolled patients between January 2020 and June 2022. Adherence to treatment was evaluated with the SMAQ questionnaire and patient satisfaction with the EQ-5D. RESULTS: Two hundred eight participants were enrolled with mean age of 35.6 years; 87.6% were males; mean CD4 count was 393.5 cells/uL (<200 cells/uL in 22.1%); viral load log was 5.6 (VL>100 000 cop/mL in 43.3%); 22.6% had AIDS, and 4.3% were coinfected with HBV. BIC/FTC/TAF was initiated on the day of their first visit to the HIV specialist in 98.6% of participants, and 9.6% were lost to follow-up. The efficacy at week 48 was 84.1 % by intention-to- treat (ITT), 94.6% by modified ITT, and 98.3% by per protocol analysis. The regimen was discontinued in two subjects (0.9%) during week 1 for grade 3 adverse events. Treatment adherence (weeks 4 [90%, IQR: 80-99%] vs. 48 [90%, IQR: 80-95%; P = 0.49]) and patient satisfaction (weeks 4 [90%, IQR: 80-99%] vs. 48 [90%, IQR: 80-95 P = 0.49]) rates were very high over the 48- week study period. CONCLUSIONS: BIC/FTC/TAF is an appropriate option for rapid ART initiation in naïve HIV patients, offering high efficacy, safety, durability, treatment adherence, retention in the healthcare system, and patient satisfaction. Number Clinical Trial registration: NCT06177574.

Renal safety of tenofovir alafenamide-based antiretroviral therapy in people with HIV: A mini-review.

Antiretroviral therapy (ART) has significantly enhanced the outlook for people with HIV(PWH), yet certain ART medications can adversely affect the renal function of these patients. Of particular concern is the nephrotoxicity associated with tenofovir disoproxil fumarate (TDF). Compared to TDF, tenofovir alafenamide (TAF), another prodrug of tenofovir (TFV), results in lower TFV plasma levels, thereby alleviating the TFV-associated mitochondrial toxicity on proximal renal tubular cells. Currently, numerous clinical trials and real-world studies have demonstrated the favorable renal safety profile of ART regimens incorporating TAF for PWH. This paper seeks to consolidate the available evidence regarding the renal safety of TAF-based regimens in PWH, encompassing both the general PWH and those with renal impairment or predisposing factors, in order to offer recommendations and insights for TAF clinical application.

Thiazolidinediones are Partially Effective Bitter Blockers.

PURPOSE: The bad bitter taste of some medicines is a barrier to overcoming noncompliance with medication use, especially life-saving drugs given to children and the elderly. Here, we evaluated a new class of bitter blockers (thiazolidinediones, TZDs). METHODS: In this study, 2 TZDs were tested, rosiglitazone (ROSI) and a simpler form of TZD, using a high-potency sweetener as a positive control (neohesperidin dihydrochalcone, NHDC). We tested bitter-blocking effects using the bitter drugs tenofovir alafenamide fumarate (TAF), a treatment for HIV and hepatitis B infection, and praziquantel (PRAZ), a treatment for schistosomiasis, by conducting taste testing with 2 separate taste panels: a general panel (N = 97, 20-23 years, 82.5% female, all Eastern European) and a genetically informative panel (N = 158, including 68 twin pairs, 18-82 years, 76% female, 87% European ancestry). Participants rated the bitterness intensity of the solutions on a 100-point generalized visual analog scale. FINDINGS: Person-to-person differences in drug bitterness were striking; TAF and PRAZ were weakly or not bitter for some people but moderately to highly bitter for others. Participants in both taste panels rated the bitter drugs TAF and PRAZ as less bitter on average when mixed with NHDC than when sampled alone. ROSI partially suppressed the bitterness of TAF and PRAZ, but effectiveness differed between the 2 panels: bitterness was significantly reduced for PRAZ but not TAF in the general panel and for TAF but not PRAZ in the genetically informative panel. ROSI was a more effective blocker than the other TZD. IMPLICATIONS: These results suggest that TZDs are partially effective bitter blockers and the suppression efficacy differs from drug to drug, from person to person, and from panel to panel, suggesting other TZDs should be designed and tested with more drugs and on diverse populations to define which ones work best with which drugs and for whom. The discovery of bitter receptor blockers can improve compliance with medication use.

Tenofovir alafenamide or tenofovir disoproxil fumarate in pregnancy to prevent HBV transmission: Maternal ALT trajectory and infant outcomes.

BACKGROUND: The use of antiviral agents, specifically tenofovir disoproxil fumarate (TDF), in pregnant women to prevent mother-to-child HBV transmission is a key step towards hepatitis elimination. However, data on using tenofovir alafenamide (TAF) is insufficient. The frequent occurrence of postpartum ALT flares may impact the clinical implementation. METHODS: The maternal and infant outcomes were compared in multi-centre trials of high viral load HBsAg/HBeAg+ pregnant women receiving TAF or TDF from the third trimester until 2 weeks postpartum with intensive follow-ups. To explore the dynamic pre- and postpartum changes in ALT levels, we used a group-based trajectory model for analysing data of 332 women from three prospective studies. RESULTS: After treatment, the maternal HBV DNA levels significantly decreased from baseline to delivery: 7.87 ± 0.59 to 3.99 ± 1.07 Log10 IU/mL TAF (n = 78) and 8.30 ± 0.36 to 4.47 ± 0.86 Log10 IU/mL (TDF, n = 53), with viral load reductions of 3.87 versus 3.83 Log10 IU/mL. The HBsAg-positive rates among 12-month-old infants were 1.28% (1/78) versus 1.82% (1/55) respectively (p = 1.00). Of the TAF or TDF-treated mothers, 25.64% versus 16.98% experienced ALT > 2X ULN, and 11.54% versus 1.89% received extended antiviral treatment. Our model revealed four distinct ALT patterns: stable ALT (87.2%), moderate (8.0%) or marked (2.4%) postpartum flares, or prepartum elevations (2.4%). CONCLUSIONS: TAF effectively reduces mother-to-child HBV transmission, but prophylaxis failure still occurred in few cases. Postpartum ALT flares are common in women receiving TAF or TDF during pregnancy. Approximately 12.8% of mothers may require extended postpartum antiviral treatment. CLINICAL TRIAL NUMBER: NCT03695029 (ClinicalTrials.gov).

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.