Effectiveness and safety of tenofovir amibufenamide in chronic hepatitis B patients.

This letter to the editor relates to the study entitled "Tenofovir amibufenamide vs tenofovir alafenamide for treating chronic hepatitis B: A real-world study", which was recently published by Peng et al. Hepatitis B virus infection represents a significant health burden worldwide and can lead to cirrhosis and even liver cancer. The antiviral drugs currently used to treat patients with chronic hepatitis B infection still have many side effects, so it is crucial to identify safe and effective drugs to inhibit viral replication.

Efficacy of first-line ART regimens based on tenofovir in HIV-infected patients with pre-existing A62V mutation in reverse transcriptase.

INTRODUCTION: The amino acid substitution A62V in reverse transcriptase was identified as a mutation correlated with virologic failure in patients on first-line therapy including tenofovir (TDF) and tenofovir alafenamide (TAF). A62V is a typically polymorphic mutation in HIV-1 sub-subtype A6, which is the most widespread virus variant in Russia. MATERIALS AND METHODS: The European EuResist (EIDB) database was queried to form two equivalent groups of patients: group 1 ‒ patients with A62V at baseline treated with TDF or TAF on the first-line therapy, group 2 ‒ patients without A62V at baseline treated with TDF or TAF on the first-line therapy. Each group included 23 patients. RESULTS: There was no statistical difference between the two groups in virologic efficacy in 4, 12, and 24 weeks after the start of antiretroviral therapy (ART) and in the frequency of virologic failures. CONCLUSION: This study has some limitations, and the exact role of A62V in the efficacy of the first-line ART based on tenofovir deserves further investigation.

Real world community-based HIV Rapid Start Antiretroviral with B/F/TAF versus prior models of antiretroviral therapy start - the RoCHaCHa study, a pilot study.

BACKGROUND: The rapid start of antiretroviral therapy (RSA) model initiates antiretroviral therapy (ART) as soon as possible after a new or preliminary diagnosis of HIV, in advance of HIV-1 RNA and other baseline laboratory testing. This observational study aims to determine if RSA with a single tablet regimen of bictegravir, emtricitabine, and tenofovir alafenamide (B/F/TAF) is an effective regimen for achieving viral suppression and accepted by patients at the time of diagnosis. METHODS: Adults newly or preliminarily diagnosed with HIV were enrolled from October 2018 through September 2021. Real world advantage, measured in days between clinical milestones and time to virologic suppression, associated with B/F/TAF RSA was compared to historical controls. RESULTS: All Study RSA participants (n = 45) accepted treatment at their first visit and 43(95.6%) achieved virologic suppression by week 48. Study RSA participants had a significantly shorter time (median 32 days) from diagnosis to ART initiation and virologic suppression, in comparison to historical controls (median 181 days) (n = 42). Qualitative feedback from study RSA participants showed high acceptance positive response to RSA. CONCLUSIONS: RSA is feasible and well accepted by patients in a real-world community-based clinic setting. Promoting RSA in community-based clinics is an important tool in ending the HIV epidemic.

Blood pressure increases are associated with weight gain and not antiretroviral regimen or kidney function: a secondary analysis from the ADVANCE trial in South Africa.

INTRODUCTION: Recent evidence has raised questions about whether newer HIV treatment regimens, including dolutegravir (DTG) and tenofovir alafenamide (TAF), are associated with increases in blood pressure (BP). METHODS: We assessed changes in BP by treatment regimen and evaluated the relative contribution of kidney function and weight gain to these changes among participants in the ADVANCE phase-3 trial clinical trial in South Africa (study dates: January 2017-February 2022). Our primary outcome of interest was a change in systolic BP (SBP) at 96 and 192 weeks, among those not receiving antihypertensive medication. The secondary outcome was treatment-emergent hypertension at these same time points, defined as BP ≥140/90 mmHg on two occasions, or initiation of antihypertensive medication after week 4 among individuals without hypertension at enrolment. We used linear regression to evaluate the relationship between change in estimated glomerular filtration rate (eGFR) and change in SBP; and Poisson regression to evaluate the relationship between change in eGFR and treatment-emergent hypertension at each time point. All models were adjusted for age, sex, treatment group and change in body mass index (BMI). RESULTS: Over 96 weeks, the average changes in SBP were 1.7 mmHg (95% CI: 0.0-3.4), -0.5 mmHg (95% CI: -2.2 to 1.7) and -2.1 mmHg (95% CI: -3.8 to 0.4) in the TAF/emtricitabine (FTC)/DTG, tenofovir disoproxil fumarate (TDF)/FTC/DTG and TDF/FTC/efavirenz (EFV) groups, respectively. This difference was significant for the TAF/FTC/DTG compared to the TDF/FTC/EFV group (p = 0.002). Over 96 weeks, 18.2% (95% CI: 13.4-22.9), 15.4% (95% CI: 11.0-19.9) and 13.3% (95% CI: 8.9-17.6) of participants developed treatment-emergent hypertension, respectively. In adjusted models, there was no significant relationship between change in eGFR and either outcome. Change in BMI was significantly associated with an increase in SBP, while age was associated with an increased risk of treatment-emergent hypertension. Adjustment for BMI also mitigated the unadjusted relationship between HIV treatment regimen and SBP where present. CONCLUSIONS: In the ADVANCE cohort, weight gain and age accounted for increases in BP and risk of treatment-emergent hypertension. HIV treatment programmes may need to integrate the management of obesity and hypertension into routine care. CLINICAL TRIAL NUMBER: NCT03122262.

HIV-1 infection kinetics, drug resistance, and long-term safety of pre-exposure prophylaxis with emtricitabine plus tenofovir alafenamide (DISCOVER): week 144 open-label extension of a randomised, controlled, phase 3 trial.

BACKGROUND: Data characterising the long-term use and safety of emtricitabine plus tenofovir disoproxil fumarate as daily oral pre-exposure prophylaxis (PrEP) are scarce and there are uncertainties regarding the value of routine HIV-1 RNA testing during oral PrEP follow-up. METHODS: The DISCOVER trial was a randomised, controlled, phase 3 trial in which cisgender men and transgender women aged 18 years and older with a high likelihood of acquiring HIV were recruited from 94 clinics in Europe and North America and randomly assigned to receive either emtricitabine plus tenofovir disoproxil fumarate (200/25 mg) tablets daily, with matched placebo tablets, or emtricitabine plus tenofovir alafenamide (200/300 mg) tablets daily, with matched placebo tablets, for at least 96 weeks. After completion of the trial, participants were offered enrolment in this 48-week open-label extension study of emtricitabine plus tenofovir alafenamide. In participants diagnosed with HIV during the randomised and open-label phases of the study, we characterised HIV-1 test results and measured HIV-1 RNA viral load retrospectively when available. Adherence based on tenofovir diphosphate concentrations in dried blood spots and genotypic resistance were assessed in participants diagnosed with HIV. Safety assessments included adverse events, laboratory parameters, and, in a subset of participants, bone mineral density. HIV-1 incidence in participants initially randomly assigned to receive emtricitabine plus tenofovir alafenamide was estimated using a Poisson distribution. Changes from baseline in safety endpoints were described in participants assigned to received emtricitabine plus tenofovir alafenamide and in those who switched from emtricitabine plus tenofovir disoproxil fumarate during the open-label phase. This trial is registered with ClinicalTrials.gov, NCT02842086, and is ongoing. FINDINGS: Between Sept 13, 2016, and June 30, 2017, 5399 participants were enrolled and randomly assigned in DISCOVER. 2699 were assigned to receive emtricitabine plus tenofovir disoproxil fumarate and 2700 were assigned to receive emtricitabine plus tenofovir alafenamide, of whom 2693 and 2694, respectively, received at least one dose of study drug. 2115 (79%) assigned to emtricitabine plus tenofovir disoproxil fumarate switched to emtricitabine plus tenofovir alafenamide in the open-label phase, and 2070 (77%) continued with emtricitabine plus tenofovir alafenamide in the open-label phase. As of data cutoff (Dec 10, 2020), after 15 817 person-years of follow-up, 27 new HIV-1 diagnoses were observed across the total study period, with three occurring during the open-label phase. In participants who were initially assigned to emtricitabine plus tenofovir alafenamide, the incidence was 0·13 per 100 person-years (95% CI 0·061-0·23; ten of 2670). Stored plasma samples were available for 23 of 27 participants, including 22 with incident infection. In four (17%) of 23 participants, retrospective testing detected HIV-1 RNA before serological HIV-1 test positivity; one was a suspected baseline infection. Of the three incident cases, all three were non-adherent to PrEP and none developed drug resistance. Among participants taking emtricitabine plus tenofovir alafenamide for up to 144 weeks, markers of glomerular filtration and proximal renal tubule dysfunction (ß2-microglobulin to creatinine ratio and retinol-binding protein to creatinine ratio) improved or remained stable at 144 weeks compared with baseline, bone mineral density in hip and lumbar spine increased or remained stable from baseline to week 144 (n=191), cholesterol and glucose concentrations remained stable, and median bodyweight increased by less than 1 kg per year. In participants who switched from emtricitabine plus tenofovir disoproxil fumarate during the open-label phase (2115 [79%] of 2693), markers of glomerular filtration and proximal renal tubule dysfunction improved or remained stable, bone mineral density increased, cholesterol concentrations increased, glucose concentrations were similar, and median bodyweight increased more compared with those who remained on emtricitabine and tenofovir alafenamide. INTERPRETATION: Routine HIV-1 RNA testing for follow-up of individuals on daily oral PrEP provides modest additional clinical benefit. Long-term use of emtricitabine and tenofovir alafenamide as daily oral PrEP is safe and well tolerated and can be an especially appropriate choice for people with bone or renal morbidities. FUNDING: Gilead Sciences.

Relationship between adherence to bictegravir/emtricitabine/tenofovir alafenamide fumarate and clinical outcomes in people with HIV in Japan: a claims database analysis.

A lack of adherence to long-term antiretroviral therapy may impact viral suppression. The current study examined the relationship between medication adherence and clinical outcomes in people with human immunodeficiency virus infection (PWH) receiving bictegravir, emtricitabine, and tenofovir alafenamide fumarate (B/F/TAF). A retrospective cohort study using two Japanese claims databases was conducted. Adherence was measured by the proportion of days covered (PDC). Patients were grouped into 3 PDC category and persistence was estimated by Kaplan-Meier method. Cox regression analysis was performed to investigate whether the PDC was associated with treatment discontinuation. Among 952 patients, 820 (86.1%), 95 (10.0%), and 37 (3.9%) patients were grouped into the PDC ≥ 90%, 80- < 90%, and < 80% groups, respectively. Across all PDC groups, more than 90% of patients who received B/F/TAF were receiving treatment at 1 year. There was no significant difference in the risk of discontinuation between the lower PDC groups (80- < 90% and < 80%) and the PDC ≥ 90% group (0.400 [0.096, 1.661]; 2.244 [0.663, 7.594], hazard ratio [95% confidence interval], respectively). A drug resistance test was implemented for 15 patients, none of whom discontinued B/F/TAF after the test. The results suggest that events that could cause discontinuation, such as virologic failure, were not associated with PDC.

Metabolic effects and cardiovascular disease risks of antiviral treatments in patients with chronic hepatitis B.

Different antiviral treatments for chronic hepatitis B (CHB) have been known to have different metabolic effects. This study aimed to reveal whether tenofovir alafenamide (TAF)-induced dyslipidemia and its associated outcomes are significant. This study utilized 15-year historical cohort including patients with CHB in Korea and consisted of two parts: the single-antiviral and switch-antiviral cohorts. In the single-antiviral cohort, patients were divided into four groups (entecavir [ETV]-only, tenofovir disoproxil fumarate [TDF]-only, TAF-only, and non-antiviral). Propensity score matching (PSM) and linear regression model were sequentially applied to compare metabolic profiles and estimated atherosclerotic cardiovascular disease (ASCVD) risks longitudinally. In the switch-antiviral cohort, pairwise analyses were conducted in patients who switched NAs to TAF or from TAF. In the single-antiviral cohort, body weight and statin use showed significant differences between groups before PSM, but well-balanced after PSM. Changes in total cholesterol were significantly different between groups (-2.57 mg/dL/year in the TDF-only group and +2.88 mg/dL/year in the TAF-only group; p = 0.002 and p = 0.02, respectively). In the TDF-only group, HDL cholesterol decreased as well (-0.55 mg/dL/year; p < 0.001). The TAF-only group had the greatest increase in ASCVD risk, followed by the TDF-only group and the non-antiviral group. In the switch-antiviral cohort, patients who switched from TDF to TAF had a higher total cholesterol after switching (+9.4 mg/dL/year) than before switching (-1.0 mg/dL/year; p = 0.047). Sensitivity analysis on data with an observation period set to a maximum of 3 years for NA treatment showed consistent results on total cholesterol (-2.96 mg/dL/year in the TDF-only group and +3.09 mg/dL/year in the TAF-only group; p = 0.001 and p = 0.005, respectively). Another sensitivity analysis conducted on statin-treated patients revealed no significant change in cholesterol and ASCVD risk. TAF was associated with increased total cholesterol, whereas TDF was associated with decreased total and HDL cholesterol. Both TAF and TDF were associated with increased ASCVD risks, and statin use might mitigate these risks.

Safety of tenofovir alafenamide in people with HIV who experienced proximal renal tubulopathy on tenofovir disoproxil.

Twenty-eight individuals who experienced proximal renal tubulopathy (PRT, Fanconi syndrome) while receiving tenofovir disoproxil initiated tenofovir alafenamide (TAF) and were followed for 5 years. None developed recurrent PRT or experienced significant changes in estimated glomerular filtration rate (by creatinine or cystatin-C), albuminuria, proteinuria, retinol-binding proteinuria, fractional excretion of phosphate, alkaline phosphatase, or bone mineral density at the lumbar spine. These data suggest that TAF is a well tolerated treatment option for individuals vulnerable to developing PRT.

Switching to tenofovir alafenamide in patients with virologically suppressed chronic hepatitis B and renal or hepatic impairment: final week 96 results from an open-label, multicentre, phase 2 study.

BACKGROUND: Phase 3 studies in patients with chronic hepatitis B have shown tenofovir alafenamide to have non-inferior efficacy to tenofovir disoproxil fumarate, with improved renal and bone safety. We conducted this study to evaluate the safety and efficacy of switching to tenofovir alafenamide in participants with chronic hepatitis B and renal or hepatic impairment. METHODS: This open-label, multicentre, phase 2 study was done in eight countries or territories at 30 sites. We recruited adults (≥18 years) with chronic hepatitis B who were virally suppressed on nucleoside or nucleotide analogues and had renal impairment (part A: moderate or severe in cohort 1 [estimated glomerular filtration rate by the Cockcroft-Gault formula (eGFRCG) 15-59 mL/min] or end-stage renal disease [eGFRCG <15 mL/min] on haemodialysis in cohort 2) or hepatic impairment including decompensation (part B: Child-Turcotte-Pugh score 7-12). Participants switched to 25 mg of tenofovir alafenamide given orally once daily for 96 weeks. The primary endpoint was the proportion of participants with viral suppression (HBV DNA <20 IU/mL) at week 24 by missing-equals-failure analysis. Efficacy (full analysis set) and safety (safety analysis set) analyses included all enrolled participants who received at least one dose of the study drug. Week 96 safety was assessed, including renal and bone parameters. This trial is registered at ClinicalTrials.gov, NCT03180619, and is completed. FINDINGS: 124 participants (93 in part A [78 in cohort 1 and 15 in cohort 2] and 31 in part B) were enrolled between Aug 11, 2017, and Oct 17, 2018, and included in the full and safety analysis sets. 106 (85%) participants completed the study. There were 69 (74%) men and 24 (26%) women in part A and 21 (68%) men and ten (32%) women in part B. At week 24, 91 (97·8%, 95% CI 92·4 to 99·7) of 93 individuals in part A (76 [97·4%, 91·0 to 99·7] of 78 in cohort 1 and 15 [100·0%, 78·2 to 100·0] of 15 in cohort 2) and 31 (100·0%, 88·8 to 100·0) in part B had HBV DNA of less than 20 IU/mL. By week 96, the most common adverse event was upper respiratory tract infection, which occurred in 14 (15%) participants in part A and in six (19%) participants in part B. Serious adverse events occurred in 20 (22%) part A participants and in ten (32%) part B participants; none were related to treatment. No treatment-related deaths occurred. At week 96, median change in estimated glomerular filtration rate (Cockcroft-Gault method) was 1·0 mL/min (IQR -2·8 to 4·5) in cohort 1 and -2·4 mL/min (-11·4 to 10·7) in part B. Mean changes in spine and hip bone mineral density were 1·02% (SD 4·44) and 0·20% (3·25) in part A and -0·25% (3·91) and 0·28% (3·25) in part B. INTERPRETATION: Tenofovir alafenamide might offer continued antiviral efficacy and a favourable safety profile for patients with renal or hepatic impairment and chronic hepatitis B switching from tenofovir disoproxil fumarate or other antivirals. FUNDING: Gilead Sciences.

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 ).

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.

Comparative Study of Treatment Outcome with Tenofovir Alafenamide and Entecavir in Patients with HBV Related Acute on Chronic Liver Failure.

Major causes of acute insult in Hepatitis B virus related acute on chronic liver failure in the Asian region are reactivation of Hepatitis B virus and super infection with hepatitis A and E virus (ACLF). Anti viral therapy should be started as soon as possible in the ACLF patients at presentation while waiting for confirmation by HBV DNA level. This randomized controlled trial was carried out at the Department of Hepatology, BSMMU, Bangladesh from September 2019 to august 2020 with Hepatitis B virus related ACLF patient. This trial was conducted among twenty seven HBV acute on chronic liver failure patient to compare Child Turcotte pugh (CTP) score, Model for end stage liver disease (MELD) score, Asia Pacific Association for study of Liver (APASL) ACLF Research consortium (AARC) score, survival of the patients and HBV DNA level at 3 months with antiviral therapy between tenofovir alafenamide (25mg) and entecavir (0.5mg) group. CTP score, MELD score and AARC score were significantly (p<0.05) decline from baseline to all subsequent follow-up at 1st (at 7 days), 2nd (at 14 days), 3rd (at 30 days) and 4th (at 90 days) in each group but non significant (p>0.05) difference occurred between two group. All twenty seven patients had detectable HBV DNA level at pre-treatment and all survived patients became undectable at 4th, 90 days follow-up. Total 10 patients (37.07%) were survived at 90 days follow-up, out of them seven patients (70.0%) were in tenofovir alafenamide group and three patients (30.0%) were in entecavir group which was statistically significant (p<0.05) in between two group. Hepatic encephalopathy and hepatorenal syndrome were most common causes of death in both groups. Both drugs tenofovir alafenamide and entecavir significantly improves liver functions but the former one is superior regarding survival.

Systemic delivery of bictegravir and tenofovir alafenamide using dissolving microneedles for HIV preexposure prophylaxis.

Human immunodeficiency virus (HIV) continues to pose a serious threat to global health. Oral preexposure prophylaxis (PrEP), considered highly effective for HIV prevention, is the utilisation of antiretroviral (ARV) drugs before HIV exposure in high-risk uninfected individuals. However, ARV drugs are associated with poor patient compliance and pill fatigue due to their daily oral dosing. Therefore, an alternative strategy for drug delivery is required. In this work, two dissolving microneedle patches (MNs) containing either bictegravir (BIC) or tenofovir alafenamide (TAF) solid drug nanoparticles (SDNs) were developed for systemic delivery of a novel ARV regimen for potential HIV prevention. According to ex vivo skin deposition studies, approximately 11% and 50% of BIC and TAF was delivered using dissolving MNs, respectively. Pharmacokinetic studies in Sprague Dawley rats demonstrated that BIC MNs achieved a long-acting release profile, maintaining the relative plasma concentration above the 95% inhibitory concentration (IC95) for 3 weeks. For TAF MNs, a rapid release of drug and metabolism of TAF into TFV were obtained from the plasma samples. This work has shown that the proposed transdermal drug delivery platform could be potentially used as an alternative method to systemically deliver ARV drugs for HIV PrEP.

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.

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.

Spontaneous reactivation of hepatitis B virus with multiple novel mutations in an elderly patient with resolved hepatitis B virus infection.

Spontaneous reactivation of the Hepatitis B virus (HBV) is rare in individuals with previously resolved infections. This report presents the case of a 71 year-old Japanese woman who experienced HBV reactivation without any prior immunosuppressive therapy or chemotherapy. Before the onset of liver injury, the patient was negative for hepatitis B surface antigen (HBsAg) but positive for hepatitis B surface antibody. She subsequently developed liver injury, with the reappearance of HBsAg and HBV DNA. The patient was successfully treated with tenofovir alafenamide, and prednisolone. Full-genome sequencing of HBV revealed subgenotype B1 without hepatitis B e-negative mutations in the precore and core promoter regions and 12 amino acid alterations in the pre-S1/S, P, and X genes. Notably, the S gene mutations D144A and K160N, which alter the antigenicity of HBsAg and potentially contribute to its reactivation, were identified. This case emphasizes the importance of vigilance for spontaneous reactivation of resolved HBV, highlighting the need for comprehensive genomic analysis to understand the associated virological intricacies.

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.

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.

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.