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.

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.

Switching from tenofovir disoproxil fumarate to tenofovir alafenamide in virologically suppressed patient with chronic hepatitis B

BACKGROUND AND AIM

Our study evaluated the outcomes of switching from tenofovir disoproxil fumarate (TDF) to tenofovir alafenamide (TAF) in patients with chronic hepatitis B (CHB). We assessed viral and biochemical responses as well as changes in the estimated glomerular filtration rate (eGFR) and bone mineral density (BMD).

METHODS

This retrospective multicenter study included CHB patients who achieved virologic response (VR) (HBV DNA < 20 IU/mL) while on TDF and were subsequently switched to TAF between April 2018 and October 2021.

RESULTS

This study included 309 patients with a median age of 59 years, and 42.1% were male. The mean duration of TDF and TAF administration were 54.0 and 37.5 months, respectively. All patients maintained VR after switching to TAF. Alanine aminotransferase (ALT) normalization rate significantly increased 6 months after switching (74.8%-83.5%; P = 0.008). Adjusted eGFR significantly improved at 6 months (+5.55 ± 10.52 mL/min/1.73 m2; P < 0.001) and 12 months (+6.02 ± 10.70 mL/min/1.73 m2; P < 0.001) after switching. In the subgroup of patients with renal impairment (eGFR < 60 mL/min/1.73 m2), significant improvement in renal function was observed at 6 months (+0.6 ± 10.5 mL/min/1.73 m2; P < 0.001) and 12 months (+1.0 ± 10.7 mL/min/1.73 m2; P < 0.001) after switching to TAF. In patients with osteoporosis (n = 182), switching to TAF resulted in significant improvement in spine and hip BMD at 12 months, with increases of 9.7% (95% CI: 7.0-12.5) and 9.4% (95% CI: 7.0-11.8), respectively.

CONCLUSION

In this real-world study, switching to TAF was effective and safe in patients, with notable improvements in ALT levels, renal function, and BMD.

Kinetics of the hepatitis B core-related antigen and treatment responses in chronic hepatitis B patients treated with tenofovir alafenamide

AIM

An association between hepatitis B core-related antigen (HBcrAg) kinetics and hepatocarcinogenesis during nucleoside (t)id analog (NA) treatment has recently been reported. HBcrAg kinetics and factors associated with HBcrAg response during tenofovir alafenamide (TAF) administration remain unclear. In this multicenter retrospective study, we aimed to clarify the efficacy and safety of TAF in treatment-naïve patients with chronic hepatitis B, focusing on the reduction in HBcrAg levels.

METHODS

Patients were treated with TAF monotherapy for 96 weeks, and the kinetics of HBcrAg during treatment and the factors associated with HBcrAg response (defined as a change in HBcrAg of -1 log IU/mL from baseline) were evaluated.

RESULTS

The study population comprised 241 patients, 36.9% of whom were HBeAg-positive. The median baseline HBcrAg level was 4.7 log IU/mL. The median change in HBcrAg from baseline was -1.1 log IU/mL at 96 weeks after treatment. The HBcrAg response rate at 96 weeks was 56.6% (43/76). Multivariate analysis revealed high alanine transaminase level as an independent baseline factor associated with HBcrAg response at 96 weeks of treatment (p = 4.53 × 10-6). No correlation was found between the HBcrAg and hepatitis B surface antigen kinetics in patients treated with TAF monotherapy.

CONCLUSIONS

In TAF monotherapy for patients with chronic hepatitis B, HBcrAg levels were significantly decreased and baseline alanine transaminase level is an important factor associated with HBcrAg reduction. As no correlation was found between HBcrAg and reduced hepatitis B surface antigen levels in this study, HBcrAg kinetics in addition to hepatitis B surface antigen may need to be monitored during TAF treatment.

Tenofovir-Diphosphate and Emtricitabine-Triphosphate Adherence Benchmarks in Dried Blood Spots for Persons with HIV Receiving Tenofovir Alafenamide and Emtricitabine-based Antiretroviral Therapy (QUANTI-TAF)

BACKGROUND

QUANTI-TAF aimed to establish tenofovir-diphosphate/emtricitabine-triphosphate (TFV-DP/FTC-TP) adherence benchmarks in dried blood spots (DBS) for persons with HIV (PWH) receiving tenofovir alafenamide/emtricitabine (TAF/FTC)-based antiretroviral therapy (ART).

METHODS

During a 16-week pharmacokinetic study, PWH received TAF/FTC-based ART co-encapsulated with an ingestible sensor to directly measure cumulative (enrollment to final visit) and 10-day adherence. At monthly visits, intraerythrocytic concentrations of TAF/FTC anabolites (TFV-DP/FTC-TP) in DBS were quantified by LC-MS/MS and summarized at steady-state (week 12 or 16) as median (IQR). Linear mixed-effects models evaluated factors associated with TFV-DP/FTC-TP.

RESULTS

84 participants (86% male, 11% female, and 4% transgender), predominantly receiving bictegravir/TAF/FTC (73%) enrolled. 92% completed week 12 or 16 (94% receiving unboosted ART). TFV-DP for <85% (7/72), ≥85%-<95% (9/72), and ≥95% (56/72) cumulative adherence was 2696 (2039-4108), 3117 (2332-3339), and 3344 (2605-4293) fmol/punches. All participants with ≥85% cumulative adherence had TFV-DP ≥1800 fmol/punches. Adjusting for cumulative adherence, TFV-DP was higher with boosted ART, lower BMI, and in non-Blacks. FTC-TP for <85% (14/77), ≥85%-<95% (6/77), and ≥95% (57/77) 10-day adherence was 3.52 (2.64-4.48), 4.58 (4.39-5.06), and 4.96 (4.21-6.26) pmol/punches. All participants with ≥85% 10-day adherence had FTC-TP ≥2.5 pmol/punches. Low-level viremia (HIV-1 RNA ≥20-<200 copies/mL) occurred at 60/335 (18%) visits in 33/84 (39%) participants (range: 20-149 copies/mL), with similar TFV-DP (3177 [2494-4149] fmol/punches) compared with HIV-1 RNA <20 copies/mL visits (3279 [2580-4407] fmol/punches).

CONCLUSIONS

We propose PK-based TFV-DP (≥1800 fmol/punches)/FTC-TP (≥2.5 pmol/punches) benchmarks in DBS for PWH receiving unboosted TAF/FTC-based ART with ≥85% adherence. In the setting of high adherence, low-level viremia was common.

Weight, anthropometric and metabolic changes after discontinuing antiretroviral therapy containing tenofovir alafenamide (TAF) in people with HIV

BACKGROUND

Antiretroviral therapy (ART)-related weight gain is of particular concern in people with HIV (PWH). While weight gain was observed among PWH receiving tenofovir alafenamide (TAF), little is known about the potential reversibility after TAF discontinuation. We evaluated weight and metabolic changes 12 months after TAF discontinuation in the Swiss HIV Cohort Study.

METHODS

We included participants who received at least six months of TAF-containing ART between January 2016 and March 2023. Using multivariable mixed-effect models, changes in weight and lipid levels were compared between individuals who continued TAF and those who switched to one of the following TAF-free regimens: TDF-based ART, dolutegravir/lamivudine (DTG/3TC), or long-acting cabotegravir/rilpivirine (CAB/RPV).

RESULTS

Of 6555 participants (median age 54 years, 24.3% female, 13% Black), 5485 (83.7%) continued and 1070 (16.3%) stopped TAF. Overall, discontinuing TAF was associated with an adjusted mean weight change of -0.54 kg (95% CI -0.98 to -0.11) after 12 months. In stratified analyses, switching from TAF to TDF led to an adjusted mean weight decrease of -1.84 kg (CI -2.72 to -0.97), and to a decrease in mean total cholesterol (-0.44 mmol/L) and triglycerides (-0.38 mmol/L) after 12 months. Switching from TAF-based ART to DTG/3TC (-0.17 kg, CI -0.82 to 0.48) or long-acting CAB/RPV (-0.64 kg, CI -2.16 to 0.89) did not lead to reductions in weight.

CONCLUSIONS

Replacing TAF with TDF in PWH led to a decrease in body weight and an improved lipid profile within one year. Weight changes were not observed among individuals who switched to DTG/3TC or long-acting CAB/RPV.

Real-world safety and effectiveness of tenofovir alafenamide for 144 weeks in Japanese patients with chronic hepatitis B

Tenofovir alafenamide (TAF), a prodrug of tenofovir, delivers high levels of active drug to hepatocytes and is given in a lower dose than tenofovir disoproxil fumarate (TDF). TAF reduces viral replication in patients with chronic hepatitis B (CHB) similar to TDF and has shown a lower risk of the renal and bone toxicities associated with TDF use. This post-marketing surveillance study examined the safety and effectiveness of TAF in treatment-naïve and -experienced CHB patients who received TAF for 144 weeks at real-world clinical sites in Japan. Safety assessments included the incidence of adverse drug reactions (ADRs), renal and bone events, and changes in selected laboratory parameters. Effectiveness was based on the proportion of patients with HBV DNA levels below the lower limit of quantitation or <29 IU/mL. This analysis included 580 patients; 18.4% of whom were treatment-naïve. The cumulative incidence of ADRs was 0.21 per 100 person-months, and the incidence of serious ADRs was 0.01 (95% CI, 0.00-0.04) per 100 person-months. There were no ADRs of declines in estimated glomerular filtration rates, renal failure or proximal tubulopathy. The most common ADR was hypophosphataemia in seven (1.2%) patients. Two (0.4%) patients each had decreased blood phosphorus, bone mineral density decreased, dizziness and alopecia. Overall, the proportion of virologically suppressed patients increased from 68.8% at baseline to 97.5% at Week 144. These results confirm the real-world safety and effectiveness of TAF in Japanese patients with CHB and are consistent with the findings of other evaluations of the safety and efficacy of TAF in CHB.

Cost-effectiveness of switching from tenofovir disoproxil fumarate to tenofovir alafenamide versus entecavir for chronic hepatitis B patients in Greece

Aim: This study assessed the clinical impact and cost-effectiveness of switching from tenofovir disoproxil fumarate (TDF) to either tenofovir alafenamide (TAF) or entecavir (ETV) in a Greek chronic hepatitis B (CHB) population. Patients & methods: A Markov model from the perspective of a third-party payer in Greece quantified the health and economic benefits of switching from TDF to either TAF or ETV over a lifetime horizon. Results: Over a lifetime, patients who switch from TDF to TAF versus patients who switch from TDF to ETV had an overall lower incidence of compensated cirrhosis (0.4% lower), decompensated cirrhosis (0.04% lower) and hepatocellular carcinoma (0.25% lower). Chronic kidney disease and end-stage renal disease were also lower in patients who switch to TAF; major osteoporotic fractures were similar for both groups. While total costs were higher for switching from TDF to TAF versus TDF to ETV due to the higher cost of TAF, switching from TDF to TAF versus ETV was cost effective with an incremental cost-effectiveness ratio of €17,113 per quality-adjusted life year. Conclusion: Switching from TDF to TAF in patients living with CHB is a cost effective strategy to reduce adverse liver disease outcomes, while improving bone- and renal-related safety outcomes.

Cost-Utility Analysis of Tenofovir Alafenamide and Entecavir in Chronic Hepatitis B Patients: A Markov Decision Model

From the perspective of health economics, the evaluation of drug-related cost effectiveness and clinical utility is crucial. We conducted a cost-utility analysis of two first-line drugs, tenofovir alafenamide (TAF) and entecavir (ETV), in the treatment of chronic hepatitis B (CHB) patients. We performed inverse probability of treatment weighting (IPTW) to match the independent variables between the two treatment groups. The incremental cost effectiveness ratio (ICER) of the two treatment groups was simulated using a decision tree with the Markov annual-cycle model. A total of 54 patients treated with TAF and 98 with ETV from January 2016 to December 2020 were enrolled. The total medical cost in the TAF group was NT$76,098 less than that in the ETV group, and TAF demonstrated more effectiveness than ETV by 3.19 quality-adjusted life years (QALYs). When the time horizon was set at 30 years, the ICER of the TAF group compared with the ETV group was -NT$23,878 per QALY, suggesting more cost savings for TAF. Additionally, with the application of TAF, over NT$366 million (approximately US$12 million) can be saved annually. TAF demonstrates cheaper medical costs and more favorable clinical QALYs than ETV. To balance health insurance benefits and cost effectiveness, TAF is the optimal treatment for CHB.

Long-Term Outcomes after Switching to Tenofovir Alafenamide in Patients with Chronic Hepatitis B

We sought to determine the long-term outcomes of chronic hepatitis B (CHB) cases switching to tenofovir alafenamide (TAF, n = 104, median age = 63.5 years). Data at switching to TAF (baseline) and those at 1, 2, 3, 4, and 5 years from switching to TAF were compared. At baseline, HB envelop antigen (HBeAg) seropositivity was found in 20 patients (19.2%), and undetectable HBV-DNA in 77 patients (74.0%). Percentage of detectable HBV-DNA significantly reduced at any time point. HB surface antigen (HBsAg) levels significantly reduced at 3, 4, and 5 years. The percentage of HBeAg seropositivity significantly reduced at 5 years. HB core related antigen levels did not significantly change. In patients with baseline HbeAg seropositivity, HbsAg levels significantly reduced at any time point, and a similar trend was found in patients without HBeAg seropositivity. In patients with baseline FIB4 index >1.85, HBsAg levels significantly reduced at 3, 4, and 5 years, and in patients with baseline FIB4 index <1.85, HBsAg levels significantly reduced at any time point. The estimated glomerular filtration rate significantly reduced only at 5 years. The discontinuation rate owing to the side effects of TAF was 0%. In conclusion, switching to TAF therapy in patients with CHB may be effective and safe at least up to 5 years.

Changes in Glomerular Filtration Rate After Switching From Tenofovir Disoproxil Fumarate to Tenofovir Alafenamide Fumarate for Human Immunodeficiency Virus Preexposure Prophylaxis

Background

Tenofovir alafenamide fumarate (TAF) was promoted as a safer alternative to tenofovir disoproxil fumarate (TDF) for human immunodeficiency virus oral preexposure prophylaxis (PrEP). It is unknown if switching from TDF to TAF translates to improved renal function. We used electronic health record (EHR) data to assess changes in creatinine-estimated glomerular filtration rate (eGFR) after switching from TDF to TAF.

Methods

We conducted a retrospective cohort study using EHR data from Kaiser Permanente Southern California. We identified individuals who switched from TDF to TAF between October 2019 and May 2022 and used time-varying propensity score matching to identify controls who were on TDF ("nonswitchers"). We then used Bayesian longitudinal modeling to compare differences in eGFR between switching and nonswitching scenarios.

Results

Among 5246 eligible individuals, we included 118 TDF to TAF switchers and 114 nonswitchers. Compared to nonswitchers, switchers had older age of starting TDF but similar body weights at index date. A higher proportion of switchers were White, on Medicare or Medicaid, and had dyslipidemia at index date. Switching to TAF was associated with a higher eGFR compared to staying on TDF in 3-15 months post-switch, but the differences were not statistically significant (eg, month 9 difference: 1.27 [95% credible interval, -1.35 to 3.89]). While most of the estimated changes showed eGFR increase associated with switching, most were <2 eGFR units. Sensitivity analyses to address missingness or nonadherence showed similar results.

Conclusions

Switching from TDF to TAF for PrEP was associated with a nonsignificant increase in eGFR. Findings need to be confirmed using larger cohorts.

Risk of hepatocellular carcinoma after curative treatment when switching from tenofovir disoproxil fumarate or entecavir to tenofovir alafenamide: A real-world multicenter cohort study

AIM

Antiviral treatment reduces the risk of developing hepatocellular carcinoma (HCC) in patients with chronic hepatitis B. However, there is a lack of high-quality evidence regarding the preventive effects of tenofovir alafenamide (TAF) on HCC. We evaluated the impact of TAF use after curative treatment on HCC recurrence.

METHODS

Patients who underwent surgery or radiofrequency ablation as a curative treatment for HCC were selected. Those patients who continued antiviral treatment with nucleos(t)ide analogs (NAs; entecavir [ETV] or tenofovir disoproxil fumarate [TDF]) or switched to TAF were included. The primary outcome was HCC recurrence, and the time-varying effect of NA use on HCC recurrence was analyzed using various statistical methods.

RESULTS

Among 2794 consecutive patients with chronic hepatitis B who received curative treatment for HCC, 199 subsequently switched from ETV or TDF to TAF. After a median of 3.0 years, 1303 patients (46.6%) experienced HCC recurrence. After propensity score matching (ratio 1:10), switching to TAF was not associated with an increased HCC recurrence (HR 1.00, 95% CI 0.68-1.47; p = 1.00) by time-varying Cox analysis. Switching to TAF was not associated with HCC recurrence in subgroups of NA (HR 1.06, 95% CI 0.67-1.67; p = 0.81 for TDF, and HR 1.09, 95% CI 0.51-2.33; p = 0.82 for ETV). Kaplan-Meier analysis showed comparable HCC recurrence-free survival between patients who switched to TAF and those who continued with their NA (p = 0.08). Time-varying Cox analyses in various subgroups confirmed the primary findings.

CONCLUSIONS

TAF is as effective as TDF and ETV in preventing HCC recurrence after curative treatment.

Atherosclerotic cardiovascular disease risk profile of patients with chronic hepatitis B treated with tenofovir alafenamide or tenofovir disoproxil fumarate for 96 weeks

BACKGROUND

Patients with chronic hepatitis B (CHB) who switch from tenofovir disoproxil fumarate (TDF) to tenofovir alafenamide (TAF) show changes in lipid profiles.

AIM

To evaluate how these changes affect cardiovascular risk.

METHODS

This pooled analysis, based on two large prospective studies, evaluated fasting lipid profiles of patients with CHB who were treated with TAF 25 mg/day or TDF 300 mg/day for 96 weeks. Patients who fulfilled the American College of Cardiology criteria (age 40-79 years, high-density lipoprotein [HDL] 20-100 mg/dL, total cholesterol [TC] 130-320 mg/dL and systolic blood pressure 90-200 mmHg) required to assess 10-year atherosclerotic cardiovascular disease (ASCVD) risk with baseline lipid data and at least one post-baseline measurement were included in the ASCVD-risk population. The 10-year ASCVD risk was calculated for patients in this population, and changes from baseline to Week 96 were assessed using intermediate- (≥7.5%) and high-risk (≥20%) cut-offs.

RESULTS

Among 1632 patients, 620 (38%) met the criteria for the ASCVD-risk population. At Week 96, fasting levels of all lipids, except TC:HDL ratio, were lower with TDF than TAF. No significant increase was observed in overall ASCVD risk or in any ASCVD-risk categories during the 96-week treatment period compared with baseline. A similar proportion of patients in the TAF and TDF treatment groups (1.3% and 2.3%, respectively; p = 0.34) reported cardiovascular events.

CONCLUSION

Despite on-treatment differences in lipid profiles with TAF and TDF, predicted cardiovascular risk and clinical events were similar for both groups after 96 weeks.

Long-term health and economic benefits of switching to tenofovir alafenamide versus continuing on entecavir in chronic hepatitis B patients with low-level viremia in Saudi Arabia

BACKGROUND

Despite the success of current treatments, many chronic hepatitis B (CHB) patients still live with low-level viremia [LLV] resulting in liver disease progression. This study evaluated the long-term health and economic impact of switching to tenofovir alafenamide (TAF) from entecavir (ETV) in Saudi Arabia (SA) in chronic hepatitis B (CHB) LLV patients.

METHODS

A hybrid decision tree Markov state-transition model was developed to simulate a cohort of patients with CHB LLV treated with ETV and switched to TAF over a lifetime horizon in SA. While on treatment, patients either achieved complete virologic response (CVR) or maintained LLV. CVR patients experienced slower progression to advanced liver disease stages as compared to LLV patients. Demographic data, transition probabilities, treatment efficacy, health state costs, and utilities were sourced from published literature. Treatment costs were sourced from publicly available databases.

RESULTS

Base case analysis found that over a lifetime horizon, switching to TAF versus remaining on ETV increased the proportion of patients achieving CVR (76% versus 14%, respectively). Switching to TAF versus remaining on ETV resulted in a reduction in cases of compensated cirrhosis (-52%), decompensated cirrhosis (-5%), hepatocellular carcinoma (-22%), liver transplants (-12%), and a 37% reduction in liver-related deaths. Switching to TAF was cost-effective with an incremental cost-effectiveness ratio of $57,222, assuming a willingness-to-pay threshold of three times gross national income per capita [$65,790/QALY].

CONCLUSIONS

This model found that switching to TAF versus remaining on ETV in SA CHB LLV patients substantially reduced long-term CHB-related morbidity and mortality and was a cost-effective treatment strategy.

Increased spine bone density in patients with chronic hepatitis B switched to tenofovir alafenamide: A prospective, multinational study

BACKGROUND

Data on patients switched to tenofovir alafenamide (TAF) from nucleos(t)ide analogues (NUCs) other than tenofovir disoproxil fumarate are limited.

AIMS

To assess the treatment and renal/bone safety outcomes following the switch to TAF.

METHODS

We prospectively enrolled adult patients with chronic hepatitis B (CHB) who switched from any NUC to TAF at 14 centres in Japan, Korea, Taiwan and the U.S. Study outcomes were viral suppression (VR; HBV DNA < 20 IU/mL), biochemical response (BR; alanine aminotransferase normalisation), and changes in estimated glomerular filtration rate (eGFR) and T-scores (L-spine) by bone absorptiometry by 24 months after switch to TAF.

RESULTS

We enrolled 270 eligible patients. Mean age was 58.1; 58.2% were male; 12.2% had cirrhosis and 73.3% previously received entecavir monotherapy. VR rate increased significantly from 95.2% to 98.8% by 24 months after the switch to TAF (p = 0.014). Between the switch and 24 months later, the mean spine T-score improved significantly from -1.43 ± 1.36 to -1.17 ± 1.38 (p < 0.0001), while there was no significant change in mean eGFR (88.4 ± 16.9-89.5 ± 16.3 mL/min/1.73 m2 , p = 0.13). On multivariable analysis adjusted for age, sex, baseline spine T-score and prior TDF or adefovir dipivoxil use, male sex was significantly associated with lower risk of worsening spine T-score (odds ratio: 0.29, p = 0.020), while age was significantly associated with a higher risk of worsening chronic kidney disease stage (OR: 1.07, p = 0.019).

CONCLUSIONS

At 24 months after the switch to TAF, VR rates and spine bone density improved significantly while renal function remained stable.

Body weight increase and metabolic derangements after tenofovir disoproxil fumarate switch to tenofovir alafenamide in patients with chronic hepatitis B

BACKGROUND

Lipid-lowering effect was observed during treatment with tenofovir disoproxil fumarate (TDF) for chronic hepatitis B (CHB). However, the metabolic features in patients switching from TDF to tenofovir alafenamide (TAF) remain unclear.

AIMS

To compare the impacts of switching from TDF to TAF or from entecavir to TAF on body weight and metabolic features in patients with CHB.

METHODS

This was a multi-centre, prospective, observational study in patients with CHB on TDF or entecavir who switched to TAF. Baseline characteristics, lipid profile and sugar profile were determined. This study received IRB approval from each hospital.

RESULTS

We enrolled 177 patients on TDF (99) or entecavir (78) and followed them for 48 weeks after the switch to TAF. At baseline, TDF-experienced patients had lower serum triglyceride, total cholesterol, high-density lipoprotein (HDL) cholesterol and low-density lipoprotein (LDL) cholesterol than entecavir-experienced patients. The switch from TDF to TAF significantly increased body weight, triglyceride, total cholesterol, HDL, LDL, fasting glucose, glycaemic haemoglobin, insulin and insulin resistance. The switch from entecavir to TAF did not affect these measures. There was no significant difference in atherosclerotic cardiovascular disease risk scores between groups.

CONCLUSIONS

The switch from TDF to TAF was associated with weight gain, derangements of lipid profile, and increased insulin resistance in patients with CHB. Long-term effects on these metabolic features need further investigation.

Assessment of Gastrointestinal Adverse Effects during the First Six Months of "Biktarvy" Antiretroviral Therapy: Age-Related Patterns and Their Relation with Changes of 5 kg Weight Loss/Gain in the Initial Treatment Period

BACKGROUND

The battle against HIV has led to the development of antiretroviral therapy (ART), including BIKTARVY®, which combines three potent agents. However, concerns about gastrointestinal side effects during the early phases of treatment have emerged, potentially impacting patient adherence and outcomes.

MATERIALS AND METHODS

This retrospective cohort study, conducted over four years in Romania, examined 222 patients initiated on BIKTARVY® therapy. Data were collected from electronic medical records, and stringent inclusion and exclusion criteria were applied to ensure data accuracy and relevance. Statistical analysis was performed to assess age-related patterns in gastrointestinal symptoms and their relation with significant weight loss.

RESULTS

This study revealed significant differences in the prevalence of gastrointestinal symptoms between age groups, with older patients experiencing more symptoms. Notably, diarrhea did not exhibit a statistically significant age-related difference. Furthermore, weight loss exceeding 5 kg was more common in older patients. Of the patients who continued BIKTARVY® therapy, 84.9% showed an increase in CD4 cell counts, and most expressed satisfaction with treatment.

CONCLUSION

Understanding age-related patterns and gastrointestinal side effects of BIKTARVY® is crucial for optimizing HIV patient care. Future research should aim to corroborate and expand upon these findings, potentially leading to improved therapeutic approaches in the ongoing fight against HIV.

Corrigendum: Difference of gut microbiota between patients with negative and positive HBeAg in chronic hepatitis B and the effect of tenofovir alafenamide on intestinal flora

[This corrects the article DOI: 10.3389/fmicb.2023.1232180.].

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.

Cell-Dependent Activation of ProTide Prodrugs and Its Implications in Antiviral Studies

The ProTide prodrug design is a powerful tool to improve cell permeability and enhance the intracellular activation of nucleotide antiviral analogues. Previous in vitro studies showed that the activation of ProTide prodrugs varied in different cell lines. In the present study, we investigated the activation profiles of two antiviral prodrugs tenofovir alafenamide (TAF) and sofosbuvir (SOF) in five cell lines commonly used in antiviral research, namely, Vero E6, Huh-7, Calu-3, A549, and Caco-2. We found that TAF and SOF were activated in a cell-dependent manner with Vero E6 being the least efficient and Huh-7 being the most efficient cell line for activating the prodrugs. We also demonstrated that TAF was activated at a significantly higher rate than SOF. We further analyzed the protein expressions of the activating enzymes carboxylesterase 1, cathepsin A, histidine triad nucleotide-binding protein 1, and the relevant drug transporters P-glycoprotein and organic anion-transporting polypeptides 1B1 and 1B3 in the cell lines using the proteomics data extracted from the literature and proteome database. The results revealed significant differences in the expression patterns of the enzymes and transporters among the cell lines, which might partially contribute to the observed cell-dependent activation of TAF and SOF. These findings highlight the variability of the abundance of activating enzymes and transporters between cell lines and emphasize the importance of selecting appropriate cell lines for assessing the antiviral efficacy of nucleoside/nucleotide prodrugs.

No evidence of rapid reversibility of tenofovir alafenamide and/or integrase strand transfer inhibitor-associated weight gain

OBJECTIVE

We aimed to determine the reversibility of at least 7% weight gain within 12 months following tenofovir alafenamide (TAF) and/or integrase strand transfer inhibitor (INSTI) discontinuation in people with HIV (PWH) from the Dutch ATHENA cohort.

DESIGN AND METHODS

PWH with at least 7% weight gain within 24 months after first switch to TAF and/or INSTI whilst being virally suppressed were selected, excluding those with comorbidities/co-medication known to be associated with weight gain. PWH who discontinued only TAF, only INSTI or TAF+INSTI, with available follow-up weight, were included. Mean weight change in the 24 months prior to and 12 months after discontinuation was modelled using mixed-effects linear regression. Factors associated with yearly weight change were assessed using linear regression.

RESULTS

In 115 PWH, discontinuing only TAF ( n  = 39), only INSTI ( n  = 53) or TAF+INSTI ( n  = 23), the adjusted mean modelled weight change in the 24 months prior to discontinuation was +4.50 kg [95% confidence interval (CI) 3.04-6.10], +4.80 kg (95% CI 2.43-7.03) and +4.13 kg (95% CI 1.50-7.13), respectively, and -1.89 kg (95% CI -3.40 to -0.37), -1.93 kg (95% CI -3.92 to +0.07) and -2.55 kg (95% CI -5.80 to +0.02) in the 12 months postdiscontinuation. A greater number of years since HIV diagnosis was associated with greater reversibility of weight gain. No associations were found between weight change postdiscontinuation and changes in NRTI backbone or anchor agent at moment of discontinuation.

CONCLUSION

There was no evidence of rapid reversibility of at least 7% TAF-associated and/or INSTI-associated weight gain after discontinuation of these agents. Studies of larger and more diverse populations of PWH are required to more fully understand the degree to which weight gain is reversible when discontinuing TAF and/or INSTI.

Successful Treatment of Tenofovir Alafenamide-Induced Lactic Acidosis: A Case Report

Nucleoside or nucleotide analogues (NAs) have the potential to cause lactic acidosis by inhibiting DNA polymerase-γ of human mitochondria and impairing aerobic metabolism. Patients may be asymptomatic, have mild non-specific symptoms, or present in multisystem organ failure. There is a paucity of data to guide management of life-threatening lactic acidosis due to NA therapy. Here we describe a case of a 60-year old critically ill male with decompensated cirrhosis secondary to hepatitis B virus (HBV) infection who developed severe lactic acidosis (13.8 mmol/L) 2 days after initiation of tenofovir alafenamide (TAF). All other possible etiologies for the elevated lactate were ruled out. Lactic acidosis resolved rapidly with TAF discontinuation and supplementation with cofactors supporting mitochondrial oxidative phosphorylation, including coenzyme Q10, levocarnitine, riboflavin, and thiamine. This case highlights the ability of TAF to cause lactic acidosis early after therapy initiation, especially in susceptible hosts, and reviews the potential role for cofactor supplementation for drug-induced mitochondrial injury.

Difference of gut microbiota between patients with negative and positive HBeAg in chronic hepatitis B and the effect of tenofovir alafenamide on intestinal flora

Background

Severe liver diseases, such as liver fibrosis, cirrhosis, and liver cancer, are mainly caused by hepatitis B virus (HBV). This study investigated the differences between gut microbiota in HBeAg-positive and negative groups of patients with chronic hepatitis B (CHB) and investigated the effect of tenofovir alafenamide (TAF) on gut microbiota.

Methods

This prospective study included patients with CHB not taking nucleoside antivirals (No-NAs group, n = 95) and those taking TAF (TAF group, n = 60). We divided CHB patients into two groups according to the HBeAg status of the subjects on the day of data collection. Phase 1 are HBeAg-negative patients and phase 2 are HBeAg-positive patients. We investigated the improvement of clinical symptoms by TAF, as well as differences in gut microbiota between different groups by 16S rRNA high-throughput sequencing.

Results

Gut microbiota demonstrated significant differences between patients with HBeAg-positive and -negative CHB. Both the No-NAs and TAF Phase 2 subgroups demonstrated significantly increased microbiota richness and diversity, showing greater heterogeneity. Additionally, the Phase 2 subgroup exhibited a low abundance of pathways associated with glucose metabolism and amino acid metabolism. The TAF group demonstrated a significantly decreased HBV load, alanine aminotransferase, and aspartate aminotransferase and a significant increase in prealbumin compared with the No-NAs group. No significant difference was found in uric acid, creatinine, blood calcium, inorganic phosphorus, eGFR, and β2-microglobulin concentrations between the two groups. Additionally, the urea level in the TAF group was significantly lower than that in the No-NAs group, but with no significant effect on other indicators such as eGFR and β2-microglobulin.

Conclusion

This study revealed significant differences in gut microbiota composition and function between patients with HBeAg-positive and -negative CHB.

Risks of metabolic syndrome in the ADVANCE and NAMSAL trials

Introduction

The ADVANCE and NAMSAL trials evaluating antiretroviral drugs have both reported substantial levels of clinical obesity in participants. As one of the main risk factors for metabolic syndrome, growing rates of obesity may drive metabolic syndrome development. This study aims to evaluate the risk of metabolic syndrome in the ADVANCE and NAMSAL trials.

Methods

The number of participants with metabolic syndrome was calculated at baseline and week 192 as central obesity and any of the following two factors: raised triglycerides, reduced HDL-cholesterol, raised blood pressure and raised fasting glucose. Differences between the treatment arms were calculated using the χ2 test.

Results

Across all visits to week 192, treatment-emergent metabolic syndrome was 15% (TAF/FTC + DTG), 10% (TDF/FTC + DTG) and 7% (TDF/FTC/EFV) in ADVANCE. The results were significantly higher in the TAF/FTC + DTG arm compared to the TDF/FTC/EFV arm (p < 0.001), and the TDF/FTC + DTG vs. the TDF/FTC/EFV arms (p < 0.05) in all patients, and in females. In NAMSAL, the incidence of treatment-emergent metabolic syndrome at any time point was 14% (TDF/3TC + DTG) and 5% (TDF/3TC + EFV) (p < 0.001). This incidence was significantly greater in the TDF/3TC/DTG arm compared to the TDF/3TC/EFV arm in all patients (p < 0.001), and in males (p < 0.001).

Conclusion

In this analysis, we highlight treatment-emergent metabolic syndrome associated with dolutegravir, likely driven by obesity. Clinicians initiating or monitoring patients on INSTI-based ART must counsel for lifestyle optimisation to prevent these effects.

Switching from entecavir to tenofovir alafenamide for maintaining complete virological response in chronic hepatitis B

Background and Aim

Hepatocellular carcinoma development can be decreased by achieving and maintaining complete virological response (CVR) in chronic hepatitis B. However, it is unclear whether switching from entecavir (ETV) to tenofovir alafenamide (TAF) could achieve and maintain CVR in patients with low-level viremia (LLV; HBV DNA ≤ 3.3 log IU/mL) or occasional detectable HBV DNA during ETV treatment. Therefore, we aimed to examine whether the switching from ETV to TAF is effective in achieving CVR in patients with LLV or occasional detectable HBV DNA.

Methods

This study comprised 45 patients who switched from ETV to TAF. All patients received ETV and TAF for >2 years, and the HBV DNA levels were measured every 3 months. Maintaining undetectable HBV DNA during 2-year period is defined as CVR. The primary endpoint is the CVR rate during ETV and TAF treatment.

Results

The CVR rate for each of the 2 years of ETV and TAF therapy was 33.3% (15/45) and 68.9% (31/45, P < 0.01), respectively, and the CVR rate increased by switching from ETV to TAF. In patients with occasional detectable HBV DNA during ETV treatment (22 patients), 15 achieved CVR and 7 maintained occasional detectable HBV DNA. In patients with LLV during ETV treatment (eight patients), three achieved CVR and five had occasional detectable HBV DNA.

Conclusion

Switching from ETV to TAF increases the CVR rate in patients with LLV or occasional detectable HBV DNA and could be an alternative treatment option.

Entecavir-induced neutropenia in an adult living donor liver transplant recipient: Successful conversion to tenofovir alafenamide

At 22 weeks post-transplantation for HBV-related cirrhosis, an adult woman developed neutropenia which was aggravated by COVID-19 (ANC 0.4 × 109/L). Covid resolution and all "conventional" modifications were ineffective. Success within 2 weeks was achieved by switching entecavir to tenofovir alafenamide. A step-by-step judicious approach to post-transplant neutropenia is vital.

Preclinical Considerations for Long-acting Delivery of Tenofovir Alafenamide from Subdermal Implants for HIV Pre-exposure Prophylaxis

PURPOSE

Long-acting formulations of the potent antiretroviral prodrug tenofovir alafenamide (TAF) hold potential as biomedical HIV prevention modalities. Here, we present a rigorous comparison of three animal models, C57BL/6 J mice, beagle dogs, and merino sheep for evaluating TAF implant pharmacokinetics (PKs).

METHODS

Implants delivering TAF over a wide range of controlled release rates were tested in vitro and in mice and dogs. Our existing PK model, supported by an intravenous (IV) dosing dog study, was adapted to analyze mechanistic aspects underlying implant TAF delivery.

RESULTS

TAF in vitro release in the 0.13 to 9.8 mg d-1 range with zero order kinetics were attained. Implants with equivalent fabrication parameters released TAF in mice and sheep at rates that were not statistically different, but were 3 times higher in dogs. When two implants were placed in the same subcutaneous pocket, a two-week creep to Cmax was observed in dogs for systemic drug and metabolite concentrations, but not in mice. Co-modeling IV and TAF implant PK data in dogs led to an apparent TAF bioavailability of 9.6 in the single implant groups (compared to the IV group), but only 1.5 when two implants were placed in the same subcutaneous pocket.

CONCLUSIONS

Based on the current results, we recommend using mice and sheep, with macaques as a complementary species, for preclinical TAF implant evaluation with the caveat that our observations may be specific to the implant technology used here. Our report provides fundamental, translatable insights into multispecies TAF delivery via long-acting implants.

Pharmacogenetics of tenofovir clearance among Southern Africans living with HIV

BACKGROUND

Tenofovir is a component of preferred combination antiretroviral therapy (ART) regimens in Africa. Few pharmacogenetic studies have been conducted on tenofovir exposure in Africa, where genetic diversity is greatest.

OBJECTIVE

We characterized the pharmacogenetics of plasma tenofovir clearance in Southern Africans receiving tenofovir disoproxil fumarate (TDF) or tenofovir alafenamide (TAF).

METHODS

Adults randomized to TAF or TDF in dolutegravir-containing arms of the ADVANCE trial (NCT03122262) were studied. Linear regression models stratified by study arm examined associations with unexplained variability in tenofovir clearance. We investigated genetic associations with polymorphisms selected a priori followed by genome-wide associations.

RESULTS

A total of 268 participants (138 and 130 in the TAF and TDF arm, respectively) were evaluable for associations. Among polymorphisms previously associated with any drug-related phenotype, IFNL4 rs12979860 was associated with more rapid tenofovir clearance in both arms (TAF: P = 0.003; TDF: P = 0.003). Genome-wide, the lowest P values for tenofovir clearance in TAF and TDF arms were LINC01684 rs9305223 (P = 3.0 × 10-8) and intergenic rs142693425 (P = 1.4 × 10-8), respectively.

CONCLUSION

Among Southern Africans randomized to TAF or TDF in ADVANCE, unexplained variability in tenofovir clearance was associated with a polymorphism in IFNL4, an immune-response gene. It is unclear how this gene would affect tenofovir disposition.

Tenofovir alafenamide versus entecavir for treating hepatitis B virus-related acute-on-chronic liver failure: real-world study

Background and aims

Real-world data regarding hepatitis B virus-related acute-on-chronic liver failure (HBV-ACLF) patients receiving tenofovir alafenamide (TAF) as an antiviral drug are limited. Hence, we evaluated the efficacy and kidney safety of TAF among this population.

Methods

A total of 272 HBV-related ACLF patients hospitalized at Xiangya Hospital of Central South University were enrolled in this retrospective research. All patients received antiviral therapy with TAF (n = 100) or ETV (n = 172) and comprehensive medical treatments.

Results

Through 1:1 propensity score matching, 100 patients were finally included in each group. At week 48, the survival rates without transplantation of the TAF group and ETV group were 76.00 and 58.00%, separately (P = 0.007). After 4 weeks of treatment, the TAF treatment group exhibited a significantly decline in HBV DNA viral load (P = 0.029). The mean estimated glomerular filtration rate was apparently improved in the TAF group compared with the ETV group (TAF 5.98 ± 14.46 vs. ETV 1.18 ± 18.07 ml/min/1.73 m²) (P < 0.05). There were 6 patients in TAF group and 21 patients in ETV group with chronic kidney disease (CKD) stage progression ≥ 1. By contrast, the ETV treatment group has a greater risk of renal function progression in CKD 1 stage patients (P < 0.05).

Conclusion

This real-world clinical study showed that TAF is more effective than ETV in reducing viral load and improving survival rate in HBV-ACLF patients and the risk of renal function decline is lower.

Clinical trial registration

https://ClinicalTrials.gov, identifier NCT05453448.

Urine Tenofovir Levels Strongly Correlate With Virologic Suppression in Patients With Human Immunodeficiency Virus on Tenofovir Alafenamide-Based Antiretroviral Therapy

We found that urine tenofovir (TFV) levels >1500 ng/mL strongly predict virologic suppression among people with human immunodeficiency virus taking tenofovir alafenamide (odds ratio, 5.66; 95% confidence interval, 1.59-20.14; P = .007). This suggests an existing point-of-care assay developed for tenofovir disoproxil fumarate will support adherence monitoring for patients on all TFV-based antiretrovirals.

First year real life experience with tenofovir alafenamide fumarate: The pythagorean cohort

Background and Aim

In chronic hepatitis B infection, antiviral therapy significantly reduces the incidence of complications. This study aimed to present real-life 12-month effectiveness and safety data for TAF.

Materials and Methods

This Pythagoras Retrospective Cohort Study included patients from 14 centers in Turkiye. The study presents 12-month results of 480 patients treated with TAF as initial therapy or after switching from another antiviral drug.

Results

The study shows treatment of about 78.1% patients with at least one antiviral agent (90.6% tenofovir disoproxil [TDF]). The rate of undetectable HBV DNA increased in both treatment-experienced and naive patients. In TDF-experienced patients, the rate of alanine transaminase (ALT) normalization increased slightly (1.6%) within 12 months, but the change was not statistically significant (p=0.766). Younger age, low albumin, and high body mass index and cholesterol were identified as risk factors for abnormal ALT after 12 months, but no linear relationship was detected. In TDF-experienced patients, renal and bone function indicators showed significant improvement three months after the transition to TAF and remained stable for 12 months.

Conclusion

Real-life data demonstrated effective virological and biochemical responses with TAF therapy. After switching to TAF treatment, gains in kidney and bone functions were achieved in the early period.

Metabolic-Related Outcomes After Switching From Tenofovir Disoproxil Fumarate to Tenofovir Alafenamide in Adults With Human Immunodeficiency Virus (HIV): A Multicenter Prospective Cohort Study

BACKGROUND

Tenofovir alafenamide (TAF) has replaced tenofovir disoproxil fumarate (TDF) in many clinical settings. However, concerns remain about potential metabolic complications of TAF. We aimed to evaluate changes in weight, laboratory markers, and metabolic-related clinical events after replacing TDF with TAF.

METHODS

Multicenter prospective cohort study in the Spanish CoRIS cohort. We included virologically suppressed adults with human immunodeficiency virus (HIV) receiving TDF for more than 12 months who either switched to TAF or maintained TDF, with no changes in the core agent. Participants were matched by propensity score. We fitted generalized equation models to assess changes in weight, blood lipids, and hepatic steatosis index, and to compare the incidence of diabetes, hypertension, and lipid-lowering drug use after 144 weeks.

RESULTS

In total, 1446 participants were matched in each group. Median age was 38 years, 85% were male, mean weight at baseline was 73 kg. Participants who switched to TAF had a mean weight increase of +0.5 kg at 144 weeks over those who maintained TDF, with no difference in the occurrence of overweight or obesity. Individuals who switched to TAF had a significant increase in total cholesterol (+7.9 mg/dL) and triglycerides (+11.2 mg/dL), with no differences in the total cholesterol-high-density lipoprotein (HDL) ratio. However, no increased incidence of diabetes, hypertension, or lipid-lowering drug use was observed after the follow-up period.

CONCLUSIONS

Switching from TDF to TAF is associated with modest weight gain and increases in total cholesterol and triglycerides, without an impact on the incidence of obesity or metabolic-related clinical events, in this Spanish cohort with a majority White male population.

Prophylactic tenofovir alafenamide for hepatitis B virus reactivation and reactivation-related hepatitis

No prospective study on the efficacy of tenofovir alafenamide (TAF), a novel tenofovir prodrug, in preventing hepatitis B virus (HBV) reactivation has yet been reported. This multicenter prospective study enrolled HBV-carriers who received TAF to prevent HBV reactivation before antitumor or immunosuppressive therapy, and patients with resolved HBV infection who experienced HBV-reactivation and received TAF to prevent HBV reactivation-related hepatitis. The efficacy of prophylactic TAF in preventing HBV reactivation and HBV reactivation-related hepatitis was evaluated at 6 and 12 months after initiating TAF. Overall, 110 patients were administered TAF to prevent HBV reactivation or HBV reactivation-related hepatitis. Three patients died owing to primary disease, whereas one patient was transferred to another hospital within 6 months after initiating TAF. Seven patients died due to primary disease, and five patients were transferred to another hospital within 12 months after initiating TAF. Therefore, 106 and 94 (77 patients with HBV infection, 17 with previous-HBV infection) patients were evaluated at 6 and 12 months after initiating TAF, respectively. No patient experienced HBV reactivation, HBV reactivation-related hepatitis, or treatment discontinuation due to HBV reactivation or adverse events of TAF after 6 and 12 months. TAF could effectively prevent HBV reactivation and HBV reactivation-related hepatitis.

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.

A phase I study to assess safety, pharmacokinetics, and pharmacodynamics of a vaginal insert containing tenofovir alafenamide and elvitegravir

Background

New multi-purpose prevention technology (MPT) products are needed to prevent human immunodeficiency virus (HIV) and herpes simplex virus type 2 (HSV2). In this study, we evaluated a fast-dissolve insert that may be used vaginally or rectally for prevention of infection.

Objective

To describe the safety, acceptability, multi-compartment pharmacokinetics (PK), and in vitro modeled pharmacodynamics (PD) after a single vaginal dose of an insert containing tenofovir alafenamide (TAF) and elvitegravir (EVG) in healthy women.

Methods

This was a Phase I, open-label, study. Women (n=16) applied one TAF (20mg)/EVG (16mg) vaginal insert and were randomized (1:1) to sample collection time groups for up to 7 days post dosing. Safety was assessed by treatment-emergent adverse events (TEAEs). EVG, TAF and tenofovir (TFV) concentrations were measured in plasma, vaginal fluid and tissue, and TFV-diphosphate (TFV-DP) concentration in vaginal tissue. PD was modeled in vitro by quantifying the change in inhibitory activity of vaginal fluid and vaginal tissue against HIV and HSV2 from baseline to after treatment. Acceptability data was collected by a quantitative survey at baseline and post treatment.

Results

The TAF/EVG insert was safe, with all TEAEs graded as mild, and acceptable to participants. Systemic plasma exposure was low, consistent with topical delivery, while high mucosal levels were detected, with median TFV vaginal fluid concentrations exceeding 200,000 ng/mL and 1,000 ng/mL for up to 24 hours and 7 days post dosing, respectively. All participants had vaginal tissue EVG concentrations of > 1 ng/mg at 4 and 24 hours post dosing. The majority had tissue TFV-DP concentrations exceeding 1000 fmol/mg by 24 - 72 hours post dosing. Vaginal fluid inhibition of HIV-1 and HSV-2 in vitro significantly increased from baseline and was similarly high at 4 and 24 hours post dosing. Consistent with high tissue TFV-DP concentrations, p24 HIV antigen production from ectocervical tissues infected ex vivo with HIV-1 significantly decreased from baseline at 4 hours post dosing. HSV-2 production from tissue also decreased post treatment.

Conclusions

A single dose of TAF/EVG inserts met PK benchmarks, with PK data supporting an extended window of high mucosal protection. PD modeling supports mucosal protection against both HIV-1 and HSV-2. The inserts were safe and highly acceptable.

Clinical trial registration

ClinicalTrials.gov, identifier NCT03762772.

Tenofovir alafenamide in blocking mother-to-child transmission of hepatitis B virus: a multi-center, prospective study

BACKGROUND

Data of tenofovir alafenamide (TAF) in preventing mother-to-child transmission (MTCT) of hepatitis B virus (HBV) are limited. This study aimed to evaluate the effectiveness and safety of TAF for preventing MTCT.

METHODS

Pregnant women with chronic HBV infection, positive for HBeAg and high-level HBV DNA, received oral TAF from gestational weeks 24-28 until postpartum week 4. All infants received HBV immunoprophylaxis. All mothers and infants were followed up until postpartum seven month. The primary outcome was the rate of MTCT at seven month.

RESULTS

Eighty-nine mothers delivered and 91 infants were born. All were followed up to postpartum seven month. TAF was initiated at a mean gestational age of 25.0 (±1.0) weeks with the mean treatment duration of 14.3 (±1.2) weeks before delivery; 92.1% (82/89) mothers discontinued TAF, the median [IQR] time was 5.9 [4.7] weeks postpartum. The HBsAg positive rate was 0% at seven months in 91 infants, no growth retardation and congenital defects. All mothers were tolerated during TAF treatment. At delivery, 82.02% (73/89) mothers achieved HBV DNA < 200,000 IU/ml, 21.35% (19/89) achieved HBV DNA < 500 IU/ml. No significant changes on the mean (±SD) serum phosphate between baseline (1.20 ± 0.10 mmol/L) and at delivery (1.21 ± 0.13 mmol/L, p > .05). Serum creatinine at delivery (52.23 ± 8.50 µmol/L) was higher than baseline (45.97 ± 5.60 µmol/L, p < .05), but within normal range. Nine of 82 mothers stopped TAF treatment after delivery had mild ALT elevation.

CONCLUSION

TAF therapy initiated during the second trimester was effective in preventing MTCT with no safety concerns for mothers and infants (ClinicalTrials.gov number, NCT04065230).

Fabrication of PEGylated Chitosan Nanoparticles Containing Tenofovir Alafenamide: Synthesis and Characterization

Tenofovir alafenamide (TAF) is an antiretroviral (ARV) drug that is used for the management and prevention of human immunodeficiency virus (HIV). The clinical availability of ARV delivery systems that provide long-lasting protection against HIV transmission is lacking. There is a dire need to formulate nanocarrier systems that can help in revolutionizing the way to fight against HIV/AIDS. Here, we aimed to synthesize a polymer using chitosan and polyethylene glycol (PEG) by the PEGylation of chitosan at the hydroxyl group. After successful modification and confirmation by FTIR, XRD, and SEM, TAF-loaded PEGylated chitosan nanoparticles were prepared and analyzed for their particle size, zeta potential, morphology, crystallinity, chemical interactions, entrapment efficacy, drug loading, in vitro drug release, and release kinetic modeling. The fabricated nanoparticles were found to be in a nanosized range (219.6 nm), with ~90% entrapment efficacy, ~14% drug loading, and a spherical uniform distribution. The FTIR analysis confirmed the successful synthesis of PEGylated chitosan and nanoparticles. The in vitro analysis showed ~60% of the drug was released from the PEGylated polymeric reservoir system within 48 h at pH 7.4. The drug release kinetics were depicted by the Korsmeyer-Peppas release model with thermodynamically nonspontaneous drug release. Conclusively, PEGylated chitosan has the potential to deliver TAF from a nanocarrier system, and in the future, cytotoxicity and in vivo studies can be performed to further authenticate the synthesized polymer.

Similar risk of kidney function decline between tenofovir alafenamide and besifovir dipivoxil maleate in chronic hepatitis B

BACKGROUND AND AIMS

Although tenofovir alafenamide (TAF) and besifovir dipivoxil maleate (BSV) are potent antiviral agents in the treatment of chronic hepatitis B (CHB) infection, their renal safety profiles have not been previously compared. This study compared the risk of kidney function decline among patients with treatment-naïve CHB treated with TAF or BSV.

METHODS

This multicenter, retrospective, longitudinal cohort study included 556 patients with treatment-naïve CHB treated with TAF (n = 366) or BSV (n = 190) between November 2017 and August 2021. The primary outcome was chronic kidney disease (CKD) progression, defined as an increase in CKD stage by at least one stage for at least three consecutive months.

RESULTS

1:1 Propensity score matching yielded 154 patients in each treatment group. The mean estimated glomerular filtration rate (eGFR) was 100.4 vs. 100.3 ml/min/1.73 m² in the TAF and BSV groups respectively. A total of 25 patients developed a progression in CKD stage ≥1, of which 13 and 12 patients were from the TAF and BSV treated groups respectively (3.1 vs. 3.3 per 1000 person-years; p = .751). The unadjusted hazard ratio for risk of progression in CKD stage ≥1 of the BSV group (vs. the TAF group) was 1.13 (95% confidence interval, 0.50-2.58; p = .758). This association persisted even after adjusting for potential confounders. Virological, serological and biochemical responses were also similar between the two treatment groups (all p > .05).

CONCLUSIONS

TAF and BSV showed a similar risk of kidney function decline in patients with treatment-naïve CHB. Further prospective randomized studies are warranted for validation.

Excessive Weight Gain: Current Antiretroviral Agents in Virologically Suppressed People with HIV

An observational cohort study was conducted with data from the Observational Pharmaco-Epidemiology Research & Analysis (OPERA) cohort to investigate weight gain among virologically suppressed people with HIV (PWH) switching to regimens containing tenofovir alafenamide/emtricitabine/(TAF/FTC). Virologically suppressed, antiretroviral therapy (ART)-experienced PWH switching to TAF/FTC with darunavir/cobicistat (DRV/c), elvitegravir/cobicistat (EVG/c), dolutegravir (DTG), or bictegravir (BIC) were selected. Cox proportional hazards models were used to assess the risk of excessive weight gain (i.e., ≥5% gain within 28 weeks or ≥10% within 54 weeks), by regimen. A linear mixed effects model with random intercept and restricted cubic splines on time was used to assess continuous changes in weight. Confounding was controlled for with both inverse probability of treatment weighting and traditional covariate adjustment. Among 5,536 PWH, 18% gained ≥5% of their weight within 28 weeks, and 9% gained ≥10% within 54 weeks. There were no differences in the risk of excessive weight gain by regimen, although there was a nonstatistically significant 20% increase in the risk of gaining ≥10% within 54 weeks with all regimens compared to DRV/c. Throughout follow-up, the mean predicted weight remained fairly constant, with no notable differentiation between regimens. Expected weight gains ranged from +0.2 to +0.3 kg at 6 months and from +0.5 to +0.6 kg at 24 months. In conclusion, in this study of virologically suppressed, ART-experienced PWH switching to regimens containing TAF/FTC and DRV/c, EVG/c, DTG, or BIC, up to 18% experienced excessive levels of weight gain. However, no statistically significant difference was observed across regimens.

Comparison between the impact of tenofovir alafenamide and that of abacavir on rapid kidney function decline: A retrospective observational study

OBJECTIVES

To compare the impact of tenofovir alafenamide (TAF) on the slope of the estimated glomerular filtration rate (eGFR) with that of abacavir in Japanese patients living with HIV infection.

METHODS

The participants in this single-centre, retrospective, observational study were Japanese patients with HIV infection who started antiretroviral therapy with TAF/emtricitabine or abacavir/lamivudine or were switched from tenofovir disoproxil fumarate/emtricitabine to TAF/emtricitabine or abacavir/lamivudine (anchor drugs remained constant) between January 2012 and December 2020. The eGFR slope was defined as the regression coefficient between eGFR and time. The study outcome was rapid kidney function decline (RKFD; eGFR slope < -5 mL/min/1.73 m² /year). The adjusted effect of TAF on the eGFR slope was compared with that of abacavir using multivariate logistic regression analysis.

RESULTS

The study included 184 patients (with 2835 eGFR data points). The median duration of exposure to TAF or abacavir was 2.6 years [interquartile range (IQR): 1.7-3.3], and the median eGFR slope was -4.1 mL/min/1.73 m² /year (IQR: -6.4 to -1.2). In all, 72 patients (39%) experienced RKFD. Patients receiving TAF were more likely to experience RKFD (adjusted odds ratio = 3.74) than those receiving abacavir. There was a significant independent association between baseline eGFR and RKFD.

CONCLUSIONS

These findings suggest that renal function should be monitored carefully after the initiation of TAF in Japanese patients with HIV infection.

Current Antiretroviral Treatment Among People With Human Immunodeficiency Virus in the United States: Findings from the Centers for AIDS Research Network of Integrated Clinic Systems Cohort

Among 14 049 people with human immunodeficiency virus in care in 2019-2020, 96% were treated with antiretroviral therapy (ART). Current antiretroviral treatment patterns highlight high uptake of guideline-recommended ART regimens including second-generation integrase strand transfer inhibitors (dolutegravir and bictegravir) and tenofovir alafenamide, especially in antiretroviral-naive individuals initiating ART.

Switching to tenofovir alafenamide for nucleos(t)ide analogue-experienced patients with chronic hepatitis B: week 144 results from a real-world, multi-centre cohort study

BACKGROUND

Tenofovir alafenamide (TAF) may be preferable to other nucleos(t)ide analogues (NA) regarding outcomes against chronic hepatitis B virus (HBV) infection.

AIMS

To evaluate the longer term virological/biochemical effectiveness of TAF and the renal safety of sequential therapy to TAF in real-world settings METHODS: This multi-centre, retrospective cohort study included consecutive adult patients who were switched from other NAs to TAF. We assessed the virological and biochemical responses up to 144 weeks. We performed sensitivity analyses for a subgroup with chronic kidney disease (CKD) at baseline.

RESULTS

We analysed the data of 391 patients with chronic hepatitis B previously treated with entecavir (ETV) (n = 174), tenofovir disoproxil fumarate (TDF) (n = 116) or an NA combination (n = 101) for ≥ 24 months. HBV DNA <10 IU/ml at week 144 was found for 99% of patients, regardless of prior NA regimen or HBV DNA level at baseline. For patients who switched from TDF to TAF, total, low-density lipoprotein, high-density lipoprotein cholesterol and triglycerides were significantly increased after the switch. Patients who switched from a nucleotide analogue to TAF had an improved estimated glomerular filtration rate, although the rate of hypophosphataemia (<2.5 mg/dl) remained 9.7% at week 144. The virological and biochemical responses of patients with CKD were similar to the overall results.

CONCLUSIONS

Switching to TAF remained effective and safe for up to 3 years. Given the increasing comorbidities related to ageing, it will be important to carefully follow the change in the lipid levels of patients with a prior TDF-based regimen.

Efficacy and safety of tenofovir alafenamide versus tenofovir disoproxil fumarate in treatment-naïve chronic hepatitis B

BACKGROUND AND AIMS

We used real-world data to evaluate the efficacy and safety of tenofovir alafenamide (TAF) compared with tenofovir disoproxil fumarate (TDF) in treatment-naïve patients with CHB.

METHODS

We analysed 2747 patients with CHB under TAF (n = 502) or TDF (n = 2245) treatments. Virological responses (VR: HBV DNA <15 IU/ml), on-treatment ALT normalization, the incidence of HCC, renal function and lipid profiles were compared between these groups. Propensity score matching of 495 pairs was conducted for these comparisons.

RESULTS

The mean age of the total cohort was 48.6 years and 58.2% of the subjects were male. Cirrhosis had a 33.3% prevalence in the population. VRs at 12, 24 and 36 months were achieved in 70.3%, 81.2% and 83.3% of the TAF and 67.9%, 84.3% and 86.1% in the TDF cases respectively (p > 0.05 for all). Normalized ALT, as determined by local laboratory criteria (<40 U/L), occurred in 79.7%, 90.6% and 86.2% of TAF the group and 78.2%, 85.8% and 85.7% of the TDF group at 12, 24 and 36 months respectively (p > 0.05 for all). The HCC risk did not statistically differ across the entire cohort or in the PS-matched cohort. The TAF group showed a lower median increase in serum creatinine from baseline during the early study period. Compared with the TAF, the TDF group showed significant decreases in total cholesterol, triglyceride and HDL, but not in LDL.

CONCLUSIONS

Real-word data indicate that TAF has comparable efficacies to TDF in terms of VR and ALT normalization, with no higher risk of HCC.

One-year efficacy of tenofovir alafenamide in patients with chronic hepatitis B: An observational study

Non-inferior antiviral efficacy and better renal safety have been reported in chronic hepatitis B patients with tenofovir alafenamide (TAF) treatment. The experience in real-world clinical practice is limited.We aimed to explore the efficacy after 1-year TAF treatment.A total of 148 patients (42 HBeAg-positive and 106 HBeAg-negative) with TAF treatment ≥1 year were included. Virological suppression (<20 IU/mL or undetectable), HBsAg level, alanine aminotransferase (ALT) normalization (≤36 U/L), and estimated glomerular filtration rate (eGFR) were analyzed at 1 year. Multivariate logistic regression analysis was performed to determine the associated factors for virological suppression and ALT normalization.Virological suppression was achieved in 83% and the 1-year median decline of hepatitis B virus DNA was 5.18 log IU/mL. ALT normalization occurred in 75.7%. HBsAg level decreased at a median of 0.27 log IU/mL with significant difference from baseline (P < .001). Baseline ALT (odds ratio [OR] 1.005, 95% confidence interval [CI] 1.000-1.010, P = .036) and hepatitis B virus DNA (OR 0.222, 95% CI 0.079-0.621, P = .004) were significant factors for 1-year virological suppression. Age (OR 1.064, 95% CI 1.003-1.130, P = .041) was associated with ALT normalization. Significant changes were observed in creatinine (mean increase 0.03 mg/dL, P = .011) and eGFR (mean decrease 2.6 mL/min/1.73 m2, P = .004) after 1-year TAF treatment.One-year TAF treatment came to good virological response, modest ALT normalization rate and significant HBsAg decline. The observation of significant changes in eGFR warranted further studies.

Higher risk of kidney function decline with entecavir than tenofovir alafenamide in patients with chronic hepatitis B

BACKGROUND AND AIMS

Entecavir (ETV) and tenofovir alafenamide (TAF) are the preferred agents in patients with predisposing factors for nephrotoxicity, but no studies to date have directly compared the renal safety of the two antiviral agents. Hence, we compared the risk of kidney function decline among patients with treatment-naïve chronic hepatitis B (CHB) treated with ETV or TAF.

METHODS

This study included 1988 patients with treatment-naïve CHB who were treated with ETV (n = 1839) or TAF (n = 149) between 2007 and 2020 for ETV and between 2017 and 2020 for TAF. The primary outcome was chronic kidney disease (CKD) progression, defined as an increase in CKD stage by at least one stage for at least three consecutive months.

RESULTS

A 1:1 propensity score match yielded 149 patients in each treatment group. The mean estimated glomerular filtration rate (eGFR) was 100.6 ml/min/1.73 m² vs. 101.3 ml/min/1.73 m² in the ETV and TAF groups respectively. A total of 61 patients developed a progression in CKD stage ≥ 1, of which 47 and 14 patients were from the ETV- and TAF-treated groups respectively (19.9 vs. 5.1 per 1000 person-years; p < .001). The risk of progression in CKD stage ≥1 was significantly higher in patients treated with ETV, even when adjusted for potential confounders (adjusted hazard ratio 4.05; 95% CI 2.14-7.68; p < .001).

CONCLUSIONS

ETV was associated with a higher risk of kidney function decline than TAF in patients with treatment-naïve CHB. Therefore, further prospective randomized studies are needed.

Tenofovir alafenamide prophylaxis post-liver transplantation: a real-world study in patients with chronic kidney disease

Background & aims

Tenofovir alafenamide fumarate (TAF) was shown equally efficacious in suppressing hepatitis B virus (HBV) but with less renal toxicity than tenofovir disoproxil fumarate (TDF). The aim of this real-world study was to evaluate renal function in post-liver transplantation (LT) patients that changed TDF with TAF.

Methods

The TAF group (n=17) included patients who switched to TAF due to low (<60 ml/min/1.73m2) Glomerular Filtration Rate (GFR). The control group included patients that remained on TDF (n=30), although some (n= 14) had chronic kidney disease (CKD) (TDF-CKD group). GFR was assessed using: i) MDRD-6 variable; ii) CKD-EPI formula; iii) radionuclide technique (rGFR).

Results

There were no significant differences between the two groups except for the presence of diabetes and follow-up period, which were more common and shorter, respectively, in the TAF group (35% vs. 10%, p=0.03; 13.7 vs. 35.5 months, p<0.001). At the end of follow-up there were no significant changes in renal function between the TAF and the TDF group or TDF-CKD group, although the numerical change in rGFR in the latter comparison was greater in the TAF group (ΔrGFR 3 vs. -2.14 ml/min, p=0.26). The use of everolimus was associated with improvement in renal function (ΔrGFR 2 vs. -7.75 ml/min, p=0.06 [TAF vs. TDF group]; 2 vs. -12 ml/min, p=0.01 [TAF vs. TDF-CKD group]). There were no TAF- related side effects or cases of HBV recurrence.

Conclusion

Conversion to TAF in post-LT patients who develop CKD does not lead to improvement of kidney function after a period of one year.

Real-World Analysis of Weight Gain and Body Mass Index Increase Among Patients with HIV-1 Using Antiretroviral Regimen Containing Tenofovir Alafenamide, Tenofovir Disoproxil Fumarate, or Neither in the United States

Background: While some studies among patients with HIV-1 suggest that antiretroviral therapy (ART) regimens containing tenofovir alafenamide (TAF) may be associated with greater weight gain than those not containing TAF, no studies have assessed the relationship between TAF doses and weight change. Objectives: To evaluate weight-related outcomes among patients with HIV-1 in the United States initiating ART containing different nucleoside reverse transcriptase inhibitors and doses. Methods: A retrospective longitudinal study was conducted using Decision Resources Group's electronic medical records (July 17, 2017-March 1, 2020). Adult patients with HIV-1 initiating ART (index date) containing TAF 25 mg, TAF 10 mg, tenofovir disoproxil fumarate (TDF), or neither TAF nor TDF on or after July 17, 2018, were included. Changes in weight and body mass index (BMI) from pre-index to 3, 6, 9, and 12 months post-index were compared between cohorts using mean differences obtained from ordinary least squares models adjusted for baseline characteristics. Time-to-weight and BMI increase ≥5% were compared using Cox models adjusted for baseline characteristics. Results: Among 1652 eligible patients (TAF 25 mg, n=710; TAF 10 mg, n=303; TDF, n=219; non-TAF/TDF, n=420), the majority (83.2%-99.5%) initiated an integrase strand transfer inhibitor, except for the TDF cohort (45.2%). Patients initiating TAF 25 mg had greater weight or BMI increase across all time points compared with patients initiating TAF 10 mg, TDF, or non-TAF/TDF regimens (mean differences in weight or BMI changes between cohorts at 12 months post-index ranged from 0.78 kg [1.72 lb] to 1.34 kg [2.95 lb] and from 0.77 kg/m2 to 1.95 kg/m2, respectively), although findings were not statistically significant for all comparisons. Compared with TAF 25 mg, time-to-weight and BMI increase ≥5% in the other treatment cohorts were longer (hazard ratios ranged from 0.77 to 0.94), although findings were generally not statistically significant. Conclusions: Among a population of patients predominantly initiating integrase strand transfer inhibitors, increases in weight and BMI post-ART initiation were common and appeared to be higher and occur more rapidly among patients receiving TAF 25 mg compared with lower TAF doses or other nucleosides. When considering long-term health consequences, weight gain is an important factor to consider when selecting an ART regimen.

Renal safety and biochemical changes for 2 years after switching to tenofovir alafenamide from long-term other nucleotide analog treatment in patients with chronic hepatitis B

BACKGROUND

Long-term use of nucleotide analogs such as adefovir (ADV) or tenofovir disoproxil fumarate (TDF) may cause renal impairment. Tenofovir alafenamide (TAF) has less systemic exposure than TDF did. The aims were to examine longitudinal changes in renal function and biochemical parameters for 2 years after switching from long-term ADV and TDF to TAF, and to explore factors associated with improved renal function after TAF in patients with chronic hepatitis B.

METHODS

The prospective observational cohort study included 306 patients with chronic hepatitis B who underwent switching from long-term TDF or ADV to TAF. The primary outcome was the changes in estimated glomerular filtration rate (eGFR) after TAF.

RESULTS

Among 306 patients, 190 (65.3%) and 106 (34.7%) had chronic kidney disease (CKD) stages 1-2 and 3a-4 at baseline. In patients with CKD stages 3a-4, the mean eGFR significantly increased until week 12 and plateaued from week 12 to year 2 (adjusted slope using linear mixed effect models: +9.01 ml/min/1.73 m² /year until week 12; p < 0.001). In contrast, the mean eGFR plateaued from baseline to year 2 in the CKD stages 1-2 subgroup. Multivariate logistic regression showed that baseline CKD stage ≥3a, steeper decline in eGFR 1 year before TAF, and shorter duration of any nucleotide analog use was significantly associated with ≥10% improvement in eGFR in year 1.

CONCLUSIONS

Switching from TDF or ADV to TAF resulted in favorable renal safety for 2 years. In CKD stage 3a-4 subgroup, eGFR after TAF was recovered in the first 12 weeks and subsequently stabilized.

Lipid Changes After Switch From TDF to TAF in the OPERA Cohort: LDL Cholesterol and Triglycerides

Background

Increases in lipids have been observed in people with HIV (PWH) switching from tenofovir disoproxil fumarate (TDF) to tenofovir alafenamide (TAF). We assessed changes in low-density lipoprotein cholesterol (LDL-C) and triglycerides (TG) following a switch from TDF to TAF.

Methods

Adults with ≥1 lipid measure before and after switch from TDF to TAF were identified in the OPERA cohort. Multivariable linear regression using generalized estimating equations was used to estimate predicted changes in lipids over time on TAF, modeled flexibly with linear splines.

Results

A total of 6451 PWH switched from TDF to TAF, of whom 4328 maintained all other agents. LDL-C increased significantly by 1.40 mg/dL/mo over the first 3 months on TAF, by 0.33 mg/dL/mo between 3 and 9 months and then plateauing beyond 9 months. TG increased significantly by 3.52 mg/dL/mo over the first 3 months of TAF, by 0.91 mg/mL/mo between 3 and 9 months and by 0.72 mg/mL/mo between 9 and 16 months, but decreased thereafter. Similar patterns were observed in analyses restricted to PWH who switched from TDF to TAF but maintained all other agents.

Conclusions

TDF-to-TAF switch was associated with LDL-C and TG increases over the first 9 to 16 months on TAF. The dynamic patterns observed cannot be attributed to changes in other agents.