Tenofovir-associated kidney toxicity in HIV-infected patients: a review of the evidence

Fanconi Syndrome in Patients With Human Immunodeficiency Virus Treated With Tenofovir-Based Antiretroviral Therapy: A Systematic Literature Review

OBJECTIVE

Several cases of Fanconi syndrome (FS), a severe form of nephrotoxicity, have been reported in patients with HIV on tenofovir-containing antiretroviral therapy. A systematic review of the published literature on tenofovir-related FS in patients with HIV was conducted.

DATA SOURCES

PubMed and Embase were queried to identify articles in English published between January 2005 and June 2023, reporting tenofovir-related FS in adults with HIV. Preclinical studies, conference/poster abstracts, commentaries and responses, and review papers were excluded.

STUDY SELECTION AND DATA EXTRACTION

Of the 256 articles screened, 57 met the inclusion criteria. These comprised 37 case reports, 11 case series, 1 cross-sectional study, 1 case-control study, 4 cohort studies, 1 single-arm open-label clinical trial, 1 sub-analysis of clinical trials, and 1 pooled analysis of clinical trials.

DATA SYNTHESIS

Among 56 cases on which information was abstracted, median age at FS diagnosis was 50 years, 51.8% were men, and duration of tenofovir use ranged from 6 weeks to 11 years. Ritonavir was co-prescribed in almost half the cases. In observational and interventional studies, incidence of FS was low. Many studies reported resolution of FS symptoms after tenofovir discontinuation. All FS occurrences were identified in those on tenofovir disoproxil fumarate (TDF), except for one patient on tenofovir alafenamide (TAF).

RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE

Continuous monitoring of signs and symptoms of renal and bone toxicity is essential for patients with HIV on tenofovir-containing therapy.

CONCLUSIONS

Occurrence of FS is low in patients with HIV treated with tenofovir-based regimens. Concomitant use of ritonavir may increase risk of FS. TAF may be a safer alternative than TDF in terms of nephrotoxicity.

A review of renal tubular acidosis

OBJECTIVE

To review the current scientific literature on renal tubular acidosis (RTA) in people and small animals, focusing on diseases in veterinary medicine that result in secondary RTA.

DATA SOURCES

Scientific reviews and original research publications on people and small animals focusing on RTA.

SUMMARY

RTA is characterized by defective renal acid-base regulation that results in normal anion gap hyperchloremic metabolic acidosis. Renal acid-base regulation includes the reabsorption and regeneration of bicarbonate in the renal proximal tubule and collecting ducts and the process of ammoniagenesis. RTA occurs as a primary genetic disorder or secondary to disease conditions. Based on pathophysiology, RTA is classified as distal or type 1 RTA, proximal or type 2 RTA, type 3 RTA or carbonic anhydrase II mutation, and type 4 or hyperkalemic RTA. Fanconi syndrome comprises proximal RTA with additional defects in proximal tubular function. Extensive research elucidating the genetic basis of RTA in people exists. RTA is a genetic disorder in the Basenji breed of dogs, where the mutation is known. Secondary RTA in human and veterinary medicine is the sequela of diseases that include immune-mediated, toxic, and infectious causes. Diagnosis and characterization of RTA include the measurement of urine pH and the evaluation of renal handling of substances that should affect acid or bicarbonate excretion.

CONCLUSIONS

Commonality exists between human and veterinary medicine among the types of RTA. Many genetic defects causing primary RTA are identified in people, but those in companion animals other than in the Basenji are unknown. Critically ill veterinary patients are often admitted to the ICU for diseases associated with secondary RTA, or they may develop RTA while hospitalized. Recognition and treatment of RTA may reverse tubular dysfunction and promote recovery by correcting metabolic acidosis.

Effects of Prolonged Administration of Tenofovir Disoproxil Fumarate-Containing Antiviral Regimen on Renal Function in Low-Risk of Kidney Injury HIV Patients

This study intended to investigate the impact of long-term tenofovir fumarate (TDF) antiviral regimen on renal function in human immunodeficiency virus (HIV)-infected patients with low-risk of kidney injury. The observational study involving 100 HIV-infected patients without underlying diseases who achieved virological suppression and immunological recovery after sustained antiviral regimen of TDF+ lamivudine+ efavirenz (TLE) for 3.19 years. Renal function, including estimated glomerular filtration rate (eGFR), blood and urine β2 microglobulin, and other parameters, was assessed every 3 months over a period of 2.5 years. The eGFR showed a slight increasement from 116.0 at month 0 to 119.7 at month 30. Blood β2 microglobulin increased from 2.02 mg/L at month 0 to 2.77 mg/L at month 30. Compared to month 0, the difference in blood β2 microglobulin was statistically significant at month 6 and months 12-30 (P < .05). The incidence of proximal renal tubular dysfunction fluctuated from 2% at month 0 to 2.5% at month 30. The urine β2 microglobulin fluctuated from 0.5 (0.3-1.1) to 0.8 (0.5-1.35) mg/L at months 18-30, which was higher than 0.41 (0.18-1.1) mg/L at month 0 (P < .05). The abnormal concentration proportion of urine β2 microglobulin fluctuated from 72.7% to 81.3% at months 18-30, which was higher than the proportion of 57.0% at month 0. The abnormal proportion of blood β2 microglobulin, urine β2 microglobulin, and proximal renal tubular dysfunction were not correlated with eGFR (r1 = 0.119, r2 = -0.008, r3 = -0.165, P > .05). Long-term TDF antiviral regimen in low-risk of kidney injury HIV-infected patients may lead to damage in the proximal renal tubules and glomeruli. Blood and urine β2 microglobulin levels may be helpful in screening for renal dysfunction.

Renal dysfunction during treatment of chronic hepatitis B with tenofovir disoproxyl fumarate and associated risk factors

OBJECTIVES

To analyze the evolution of glomerular filtration rate (GFR) and the presence of renal tubular dysfunction during the treatment of chronic hepatitis B virus (HBV) infection with tenofovir disoproxil fumarate (TDF) and to determine the risk factors involved.

METHODS

Retrospective cohort observational study of adults with chronic hepatitis B. Exclusion: hepatitis C virus-HBV coinfection, diabetes, baseline GFR less than 60 ml/min. Measurements of serum and urinary creatinine and phosphate; urinary albumin, retinol-binding protein (RBP) and neutrophil gelatinase-associated lipocalin (NGAL) were performed. Univariate and multivariate analyses tracked factors associated with worsening GFR.

RESULTS

A total of 120 individuals were included: 35% NAÏVE (G1); 49.2% HBV using TDF (G2); 15.8% HBV-HIV using TDF (G3); 63.3% men; 60.8% white; 30% hypertensive. Average age was 50.5 years (SD ± 12.9 years). Reactive HBeAg predominated in G3 ( P  < 0.001) and cirrhosis in G2 ( P  < 0.036). NGAL was elevated in 5.3% of cases (G1 = 3.2%; G2 = 8.7%; G3 = 0%; P  = 0.582), RBP in 6.7% (G1, G3 = 0%; G2 = 13.6%; P  = 0.012), urinary phosphate/creatinine ratio in 16.2% (G1 = 15.2%; G2 = 14.5%; G3 = 23.5%; P  = 0.842) and urinary albumin/creatinine ratio in 12.9% (G1 = 12.2%; G2 = 10.7%; G3 = 21.1%; P  = 0.494). Worsening of renal function occurred in 22.5% of the population (G1 = 11.9%; G2 = 28.8%; G3 = 26.3%; P  = 0.122), independently associated only with systemic arterial hypertension [adjusted odds ratio (AOR) = 4.14; P  = 0.008], but not to TDF (AOR = 2.66; P  = 0.110) or male sex (AOR = 2.39; P  = 0.135). However, the concomitance of these variables generated a high estimated risk for this outcome (51%).

CONCLUSIONS

Renal tubular dysfunction was uncommon according to NGAL, RBP or urinary phosphate/creatinine ratio. TDF was not an independent factor for worsening renal function, significantly associated only with systemic arterial hypertension. However, in hypertensive men, the use of TDF should be monitored.

Renal function and lipid metabolism in Japanese HIV-1-positive individuals 288 weeks after switching from tenofovir disoproxil fumarate to tenofovir alafenamide fumarate: a single-center, retrospective cohort study

BACKGROUND

Continued use of tenofovir disoproxil fumarate (TDF), an antiretroviral drug, causes renal function decline and tubular damage in individuals with HIV. While tenofovir alafenamide fumarate (TAF) may have less damaging effects, it causes weight gain and abnormal lipid metabolism.

METHODS

This single-center, retrospective cohort study used medical records from the National Hospital Organization Sendai Medical Center to investigate renal function of Japanese HIV-1-positive individuals who switched from TDF to antiretroviral therapy including TAF by 2017. The endpoints were: estimated glomerular filtration rate (eGFR), urinary β2 microglobulin (Uβ2MG), weight, and lipid metabolism parameters at 288 weeks after switching. Possible correlation between eGFR and Uβ2MG and factors affecting eGFR decline were examined.

RESULTS

Sixty patients switched from TDF to TAF and continued therapy for 288 weeks. eGFR showed a significant decline after 144 weeks, although it was controlled from the time of change until 96 weeks. In the renal impairment group, the decline was suppressed until week 288. Uβ2MG continued to decrease significantly after 48 weeks. However, the suggested correlation between eGFR and Uβ2MG disappeared when patients switched from TDF to TAF. Weight and lipid metabolic parameters increased significantly at 48 weeks and were maintained. Factors associated with decreased eGFR were: history of acquired immune deficiency syndrome (AIDS) and Uβ2MG. However, considering the odds ratio, the switch from TDF to TAF suppressed the eGFR decline in the group with a history of AIDS, and Uβ2MG had no effect on the eGFR decline.

CONCLUSIONS

Switching from TDF to TAF for the long term slows eGFR decline, decreases Uβ2MG levels, and reduces worsening of renal function. Weight gain and abnormal lipid metabolism may occur in the short term but are controllable.

Precision nephrotoxicity testing using 3D in vitro models

Nephrotoxicity is a significant concern during the development of new drugs or when assessing the safety of chemicals in consumer products. Traditional methods for testing nephrotoxicity involve animal models or 2D in vitro cell cultures, the latter of which lack the complexity and functionality of the human kidney. 3D in vitro models are created by culturing human primary kidney cells derived from urine in a 3D microenvironment that mimics the fluid shear stresses of the kidney. Thus, 3D in vitro models provide more accurate and reliable predictions of human nephrotoxicity compared to existing 2D models. In this review, we focus on precision nephrotoxicity testing using 3D in vitro models with human autologous urine-derived kidney cells as a promising approach for evaluating drug safety.

The clinical impact of rifampicin-based anti-TB therapy and tenofovir alafenamide-containing ARV regimen drug Interaction in people living with HIV: Case series report

BACKGROUND

People living with HIV (PLWH) are prone to developing tuberculosis (TB). Since tenofovir alafenamide (TAF) is the recommended tenofovir (TFV) prodrug and rifampicin is a key component of TB therapy, thus complicating HIV and TB coinfection management. However, there is little data regarding the impact of this drug-drug Interaction in PLWH, which makes health care providers reluctant to prescribe them together.

METHODS

This was an observational, retrospective case series carried out at King Faisal Specialist Hospital & Research Center (KFSH&RC), Jeddah, Saudi Arabia. PLWH (≥18 years old) who received the TAF-containing ARV regimen and rifampicin-based anti-TB therapy together for ≥ 4 weeks were included. The objective of this study was to report the clinical impact of this drug-drug interaction (rifampicin + TAF-containing antiretroviral (ARV) regimen) on HIV viral load control in PLWH.

RESULTS

A total of 7 PLWH who met the inclusion criteria, 5 (71 %) out of 7, were males. All patients received dolutegravir 50 mg twice daily (DTG) plus the combination of TAF 25 mg and emtricitabine 200 mg (FTC) once daily as their ARV regimen. Four patients had suppressed viral load levels at baseline, which was maintained throughout TB treatment. Three patients had unsuppressed viral load levels at baseline and attained viral load suppression throughout the TB treatment course CONCLUSION: Overall, the TAF-containing ARV regimen maintained it's efficacy in presence of rifampicin.

Tenofovir disoproxil fumarate versus tenofovir alafenamide on risk of osteoporotic fracture in patients with chronic hepatitis B: A nationwide claims study in South Korea

BACKGROUND

As tenofovir disoproxil fumarate (TDF) requires long-term use, a reduction in bone density should be considered a possibility when treating patients with chronic hepatitis B (CHB) with aging and systemic diseases. Patients treated with tenofovir alafenamide (TAF) have improved bone mineral density loss compared to patients treated with TDF. Although improvements in bone density caused by TAF have been reported, studies on the actual reduction of fractures are insufficient.

AIM

To evaluate the impact of TAF on the risk of osteoporotic fractures in comparison with that of TDF.

METHODS

Using the national claims data of the Health Insurance Review and Assessment Service, we conducted a retrospective cohort study of 32,582 patients with CHB who had been initially treated with TDF or TAF between November 2017 and December 2020. The numbers of patients treated with TDF and TAF were 20,877 and 11,705, respectively. The annual fracture rate per 100 patients in each group was calculated, and the Cox proportional hazard ratio (HR) was analysed after applying inverse probability treatment weights (IPTW) for both groups.

RESULTS

Among 32,582 patients, the average age was 47.8 ± 11.2 years, 64.5% were men, and the follow-up period was 24.4 ± 11.6 months. The incidence of osteoporotic fractures was 0.78 and 0.49 per 100 person-years in the TDF and TAF groups, respectively. After application of IPTW, the HR was 0.68 (95% confidence interval 0.55-0.85, p = 0.001).

CONCLUSION

TAF-treated patients with CHB had a significantly lower risk of osteoporotic fracture than TDF-treated patients.

Secondary metabolites of Bacillus subtilis L2 show antiviral activity against pseudorabies virus

Bacillus subtilis (B. subtilis) is a commercially important probiotic known to produce secondary metabolites with antibacterial, antifungal and anti-inflammatory activities. However, the potential ability of B. subtilis to combat viruses, especially DNA viruses, has not been extensively investigated. In this study, we identified two distinct B. subtilis strains and examined the efficiency of their secondary metabolites against pseudorabies virus (PRV), a swine herpesvirus resulting in economic losses worldwide. We found that treatment with the secondary metabolites of B. subtilis L2, but not the metabolites of B. subtilis V11, significantly inhibited PRV replication in multiple cells. Notably, the antiviral activity of the metabolites of B. subtilis L2 was thermal stable, resistant to protease digestion. Moreover, these metabolites effectively impeded PRV binding, entry and replication. Importantly, oral administration of the metabolites of B. subtilis L2 protected mice from lethal PRV infection, rescuing weight loss and reducing the viral load in vivo. In summary, our results reveal that the metabolites of B. subtilis L2 exhibit anti-PRV activity both in vitro and in vivo, providing a potential candidate for novel antiviral drugs.

Effect of P-glycoprotein and Cotreatment with Sofosbuvir on the Intestinal Permeation of Tenofovir Disoproxil Fumarate and Tenofovir Alafenamide Fumarate

PURPOSE

We aimed to compare the effects of P-glycoprotein (ABCB1) on the intestinal uptake of tenofovir disoproxil fumarate (TDF), tenofovir alafenamide fumarate (TAF), and metabolites, tenofovir isoproxil monoester (TEM) and tenofovir (TFV), and to study the molecular mechanism of drug-drug interaction (DDI) between sofosbuvir (SOF) and TDF/TAF.

METHODS

Bidirectional transport experiments in Caco-2 cells and accumulation studies in precision-cut intestinal slices prepared from the ileal segment of rodent (rPCIS) and human (hPCIS) intestines were performed.

RESULTS

TDF and TAF were extensively metabolised but TAF exhibited greater stability. ABCB1 significantly reduced the intestinal transepithelial transfer and uptake of the TFV(TDF) and TFV(TAF)-equivalents. However, TDF and TAF were absorbed more efficiently than TFV and TEM. SOF did not inhibit intestinal efflux of TDF and TAF or affect intestinal accumulation of TFV(TDF) and TFV(TAF)-equivalents but did significantly increase the proportion of absorbed TDF.

CONCLUSIONS

TDF and TAF likely produce comparable concentrations of TFV-equivalents in the portal vein and the extent of permeation is reduced by the activity of ABCB1. DDI on ABCB1 can thus potentially affect TDF and TAF absorption. SOF does not inhibit ABCB1-mediated transport of TDF and TAF but does stabilise TDF, albeit without affecting the quantity of TFV(TDF)-equivalents crossing the intestinal barrier. Our data thus suggest that reported increases in the TFV plasma concentrations in patients treated with SOF and TDF result either from a DDI between SOF and TDF that does not involve ABCB1 or from a DDI involving another drug used in combination therapy.

Ethyl Gallate: Promising Cytoprotective against HIV-1-Induced Cytopathy and Antiretroviral-Induced Cytotoxicity

Introduction

HIV-1 infection in cell culture is typically characterized by certain cytopathic effects such as vacuolization of cells and development of syncytia, which further lead to cell death. In addition, the majority of drugs during HIV treatment exhibit serious adverse effects in patients, apart from their beneficial role. During the screening of cytoprotective agents to protect the cells from HIV-1-associated cell death and also drug-associated toxicity, antioxidants from a natural source are assumed to be a choice. A well-known antioxidant, ethyl gallate (EG), was selected for cytoprotection studies which have already been proven as an anti-HIV agent.

Objective

The main objective of the study was to explore the cytoprotective potential of EG against HIV-1-induced cytopathic effect and antiretroviral drug toxicity.

Methods

DPPH free radical scavenging assay was performed with EG to find the effective concentration for antioxidant activity. HIV-1infection-associated cytopathic effects and further rescue by EG were studied in MT-2 lymphocytes by the microscopic method and XTT cytopathic assays. The cellular toxicity of different antiretroviral drugs in different cell lines and the consequent cytoprotective effectiveness of EG were investigated using an MTT cell viability assay.

Results

Like ascorbic acid, EG exhibited promising antioxidant activity. HIV-1 infection of MT2 cells induces cell death often referred to as the cytopathic effect. In addition, the usage of antiretroviral drugs also causes severe adverse effects like cytotoxicity. In this context, EG was tested for its cytoprotective properties against HIV-1-induced cytopathic effect and drug-mediated cellular toxicity. EG reclaimed back the MT2 cells from HIV-1-induced cell death. Antiretroviral drugs, such as ritonavir, efavirinz, AZT, and nevirapine, were tested for their toxicity and induced more cell death at higher concentrations in different tissue models such as the liver (THLE-3), lung (AEpiCM), colorectal (HT-29), and brain (U87 MG). Pretreated cells with EG were rescued from the toxic doses of ART.

Conclusion

EG was found to be exhibited cytoprotection not only from HIV-1-linked cell death but also from the chemotoxicity of antiretroviral drugs. Evidently, EG could be a cytoprotective supplement in the management of AIDS along with its enormous antioxidant benefits.

Acquired Fanconi Syndrome from Tenofovir Treatment in a Patient with Hepatitis B

Fanconi syndrome is a rare disease of generalized proximal tubule dysfunction which can be acquired secondary to certain medications, including tenofovir, a commonly used hepatitis B treatment. Signs and symptoms of ensuing renal wasting can be severe but vague, leading to potentially avoidable invasive investigations and delays in diagnosis. We present a case of a 62-year-old female with chronic hepatitis B on tenofovir treatment who was found to have subacute weakness, anorexia, and weight loss. She underwent extensive investigations including computed tomography (CT) imaging, bronchoscopy, upper and lower endoscopy, and psychiatric evaluation. Finally, persistent electrolyte derangements led to urine studies, which demonstrated acquired Fanconi syndrome secondary to tenofovir. After discontinuing tenofovir disoproxil fumarate and starting tenofovir alafenamide, her symptoms resolved and her renal function recovered. This case illustrates the importance of maintaining clinical suspicion for tenofovir-induced Fanconi syndrome, given the common use of tenofovir as first-line hepatitis B treatment and the availability of less nephrotoxic alternatives.

Antivirals for prevention of hepatitis B virus mother-to-child transmission in human immunodeficiency virus positive pregnant women co-infected with hepatitis B virus

BACKGROUND

Hepatitis B virus (HBV)-human Immunodeficiency virus (HIV) co-infection promotes an aggressive disease course of HBV infection. In the only available non-Cochrane systematic review on antiviral therapy during pregnancy for prevention of mother-to-child transmission of HBV, none of the women studied had HBV-HIV co-infection but were either HBV- or HIV-seropositive. Treatment of HBV alone may develop HIV-strains that are resistant to non-nucleoside reverse transcriptase inhibitors. Accordingly, co-treatment of the HIV infection is recommended.

OBJECTIVES

To evaluate the benefits and harms of tenofovir-based antiviral combination regimens versus placebo, tenofovir alone, or non-tenofovir-based antiviral regimen either alone or in combination with HBV for the prevention of mother-to-child transmission of HBV in HIV-positive pregnant women co-infected with HBV.

SEARCH METHODS

We searched the Cochrane Hepato-Biliary Group Controlled Trials Register, Cochrane Central Register of Controlled Trials, MEDLINE Ovid, Embase Ovid, LILACS (Bireme), Science Citation Index Expanded (Web of Science), and Conference Proceedings Citation Index-Science (Web of Science) on 30 January 2023. We manually searched the reference lists of included trials, searched on-line trial registries, and contacted experts in the field and pharmaceutical companies for any further potential trials.

SELECTION CRITERIA

We aimed to include randomised clinical trials comparing tenofovir-based antiviral combination regimens (anti-HIV regimen with lopinavir-ritonavir therapy, or any other antiviral therapy, and two drugs with activity against HBV, specifically, tenofovir alafenamide (TAF) or tenofovir disoproxil fumarate (TDF), plus lamivudine or emtricitabine) with placebo alone, or tenofovir alone, or non-tenofovir-based antiviral regimen (zidovudine, lamivudine, telbivudine, emtricitabine, entecavir, lopinavir-ritonavir, or any other antiviral therapy) either alone or in combination with at least two other antivirals.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. Primary outcomes included all-cause infant mortality, proportion of infants with serious adverse events, proportion of infants with HBV mother-to-child transmission, all-cause maternal mortality, and proportion of mothers with serious adverse events. Secondary outcomes included proportion of infants with adverse events not considered serious, proportion of mothers with detectable HBV DNA (deoxyribonucleic acid) (before delivery), maternal hepatitis B e antigen (HBeAg) to HBe-antibody seroconversion (before delivery) and maternal adverse events not considered serious. We used RevMan Web to carry out analyses and presented results, where feasible, using a random-effects model and risk ratios (RR) with 95% confidence intervals (CIs). We performed sensitivity analysis. We assessed risk of bias using predefined domains, assessed the certainty of the evidence using GRADE, controlled risk of random errors with Trial Sequential Analysis, and presented outcome results in a summary of findings table.

MAIN RESULTS

Five completed trials were included, of which four trials contributed data to one or more of the outcomes. They included a total of 533 participants randomised to tenofovir-based antiviral combination regimens (196 participants) versus control (337 participants). The control groups received non-tenofovir-based antiviral regimens either as zidovudine alone (three trials) or as a combination of zidovudine, lamivudine and lopinavir-ritonavir (five trials). None of the trials used placebo or tenofovir alone. All trials were at unclear risk of bias. Four trials used intention-to-treat analyses. In the remaining trial, two participants in the intervention group and two in the control group were lost to follow-up. However, the outcomes of these four participants were not described. Tenofovir-based antiviral combination regimen versus control We are very uncertain about the effect of a tenofovir-based antiviral combination regimen versus control on all-cause infant mortality (RR 2.24, 95% CI 0.72 to 6.96; participants = 132; trials = 1; very low-certainty evidence); proportion of infants with serious adverse events (RR 1.76, 95% CI 1.27 to 2.43; participants = 132; trials = 1; very low-certainty evidence), and proportion of mothers with serious adverse events (RR 0.90, 95% CI 0.62 to 1.32; participants = 262; trials = 2; very low-certainty evidence). No trial reported data on the proportion of infants with HBV mother-to-child transmission and all-cause maternal mortality. We are also very uncertain about the effect of tenofovir-based antiviral combination regimens versus control on the proportion of infants with adverse events not considered serious (RR 0.94, 95% CI 0.06 to 13.68; participants = 31; trials = 1; very low-certainty evidence), and proportion of mothers with detectable HBV DNA (before delivery) (RR 0.66, 95% CI 0.42 to 1.02; participants = 169; trials = 2; very low-certainty evidence). No trial reported data on maternal hepatitis B e antigen (HBeAg) to HBe-antibody seroconversion (before delivery) and maternal adverse events not considered serious. All trials received support from industry.

AUTHORS' CONCLUSIONS

We do not know what the effects of tenofovir-based antiviral combination regimens are on all-cause infant mortality, proportion of infants with serious adverse events and proportion of mothers with serious adverse events, proportion of infants with adverse events not considered serious, and proportion of mothers with detectable HBV DNA before delivery because the certainty of evidence was very low. Only one or two trials, with insufficient power, contributed data for analyses. We lack randomised clinical trials at low risk of systematic and random errors, and fully reporting all-cause infant mortality, serious adverse events and reporting on clinical and laboratory outcomes, such as infants with HBV mother-to-child transmission, all-cause maternal mortality, maternal hepatitis B e antigen (HBeAg) to HBe-antibody seroconversion before delivery and maternal adverse events not considered serious.

Fanconi syndrome in an elderly patient with membranous nephropathy during treatment with the immunosuppressant mizoribine

We report on an 80-year-old man diagnosed with Fanconi syndrome induced by mizoribine after 4 weeks of administration to treat membranous nephropathy. Mizoribine is an oral immunosuppressant that inhibits inosine monophosphate dehydrogenase and is widely used in Japan for the treatment of autoimmune diseases and nephrotic syndrome, as well as after renal transplantation. Acquired Fanconi syndrome is often caused by drugs (antibacterial, antiviral, anticancer, and anticonvulsant drugs) and is sometimes caused by autoimmune diseases, monoclonal light chain-associated diseases, or heavy metal poisoning. In our patient, hypokalemia, hypophosphatemia, glucosuria, hypouricemia, and severe proteinuria resolved gradually after discontinuation of mizoribine administration, despite oral administration of prednisolone followed by a single intravenous injection of rituximab. The patient was ultimately diagnosed with Fanconi syndrome induced by mizoribine based on his clinical course and his typical laboratory data with the absence of proximal tubular acidosis. To our knowledge, this is the first report of Fanconi syndrome possibly induced by mizoribine. Although the precise mechanism by which mizoribine induces proximal tubular dysfunction is unknown, we suggest that nephrologists should be aware of the onset of Fanconi syndrome, a rare complication during mizoribine treatment.

A prospective cohort study of renal function and bone turnover in adults with hepatitis B virus (HBV)-HIV co-infection with high prevalence of tenofovir-based antiretroviral therapy use

OBJECTIVE

Tenofovir disoproxil fumarate (TDF) is a common component of antiretroviral therapy in hepatitis B virus (HBV)-HIV co-infected adults but few studies have evaluated worsening renal function and bone turnover, known effects of TDF.

METHODS

Adults from eight North American sites were enrolled in this cohort study. Research assessments were conducted at entry and every 24 weeks for ≤192 weeks. Bone markers were tested at baseline, week 96 and week 192 from stored serum. We evaluated changes in markers of renal function and bone turnover over time and potential contributing factors.

RESULTS

A total of 115 patients were prospectively followed; median age 49 years, 91% male and 52% non-Hispanic Black. Duration of HIV was 20.5 years. TDF use ranged from 80% to 92% throughout follow-up. Estimated glomerular filtration rate (eGFR) (ml/min/1.73m² ) decreased from 87.1 to 79.9 over 192 weeks (p < 0.001); however, the prevalence of eGFR <60 ml/min/1.73m² did not appear to differ over time (always <16%; p = 0.43). From baseline to week 192, procollagen type I N-terminal propeptide (P1NP) (146.7 to 130.5 ng/ml; p = 0.001), osteocalcin (14.4 to 10.2 ng/ml; p < 0.001) and C-terminal telopeptides of type I collagen (CTX-1) (373 to 273 pg/ml; p < 0.001) decreased. Younger age, male sex and overweight/obesity versus normal weight predicted a decrease in eGRF. Black race, healthy weight versus underweight, advanced fibrosis, undetectable HBV DNA, and lower parathyroid hormone level predicted worsening bone turnover.

CONCLUSION

In this HBV-HIV cohort with high prevalence of TDF use, several biomarkers of renal function and bone turnover indicated worsening status over approximately 4 years, highlighting the importance of clinical awareness in co-infected adults.

Comparison of Metabolic Effects of Three Different Treatment Combinations with Retrospective Real-life Data in People Living with HIV

INTRODUCTION

Comorbidities are increasing in people living with HIV (PLHIV), and different treatment options have advantages and disadvantages. It is important to compare information from real-life treated cases. The aim of this study was to retrospectively evaluate the data on efficacy and clinical and laboratory findings during different antiretroviral therapies.

METHODS

Retrospective file data of 47 PLHIV using Dolutegravir and Lamivudine (3TC/DTG), Tenofovir Alafenamide Emtricitabine and Elvitegravir Cobicistat (EVG/c/TAF/FTC) and Tenofovir Disoproxil Fumarate and Emtricitabine and Efavirenz (EFV/FTC/TDF) were analyzed. Data of the patients at baseline and 12 months after antiretroviral therapy (ART) were compared.

RESULTS

About 47 PLHIV were included in the study. Of the patients, 22 (46.8%) were in the 3TC/DTG group, 19 (40.4%) in the EVG/c/TAF/FTC, and 6 (12.8%) in the EFV/FTC/TDF group. After 12 months of treatment, BMI, HIV-RNA, CD4, WBC, hemoglobin, MCV, PDW, RDW, platelet count, creatinine, eGFR, HDL, AST, glucose values of the 3TC/DTG group were significantly different (p<0.05). After 12 months of treatment, BMI, HIV-RNA, CD4 count, MCV, creatinine, eGFR, HDL, LDL, TG, TC, AST, and HOMA-IR values of the EVG/c/TAF/FTC treatment group were significantly different (p<0.05). After 12 months of treatment, HIV RNA, total bilirubin, and LDL values in the EFV/FTC/TDF treatment group were statistically different (p<0.05).

CONCLUSION

All treatment groups showed a decrease in HIV-RNA and an increase in CD4 at the end of one year. While CD4 elevation is lower in EFV recipients than in integrase inhibitor (INSTI) recipients, weight gain is higher in INSTI recipients. While the lipid profile was more positively affected in the 3TC/DTG group, lipid profiles were more negatively affected in the EVG/c/TAF/FTC group, although liver and kidney functions were preserved.

Effect of tenofovir containing ART on renal function in patients with moderate/severe reduced creatinine clearance at baseline: A retrospective study at two referral hospitals in Namibia

Prescription of tenofovir disoproxil fumarate (TDF) for patients with baseline creatinine clearances (CrCl) <60 mL/min is said to increase risk of further decline in CrCl. Study objectives were to assess incidence of improvement and predictors thereof; to assess incidence of decline and transition to lower stages of CrCl; and comparison of declines between patients with a baseline CrCl < 60mL/min (group-I) and ≥ 60 mL/min (group-II). The study was retrospective, included patients 16 yrs or older who received TDF-containing ART. Improvement and decline were defined as ≥ 25% increase or decrease in CrCl, respectively. Binary logistic regression was performed to identify predictors of improvement. Groups I and II had 2862 and 7526 patients, respectively. In group-I, improvement in CrCl was observed in 40.1% (n = 1146), and was associated with stage IV of CrCl (adjusted Odds Ratio [aOR]=13.4 [95% CI: 6.7 - 26.9, P < .001]); male gender (aHR = 1.8 [95% CI: 1.5 - 2.2, P < .001]); and a poor HIV-status (aHR = 1.2 [95% CI: 1.0 - 1.4], P = .033). In group-I and group-II, respectively, decline occurred in 2.3% and 13.0%, (P < .001); transition to lower stages occurred in 1.0% and 25.2% (P < .001); and migration to stage IV CrCl occurred in 1.0% and 0.5% (P < .001). Improvement was more likely than decline in group-I patients. Although, group-I patients were more likely to experience new onset severe reduced CrCl than group-II patients, the proportions were extremely low. TDF should not be withheld from HIV-positive patients with a baseline CrCl < 60 mL/min.

Nucleotide and nucleoside-based drugs: past, present, and future

Nucleotide and nucleoside-based analogue drugs are widely used for the treatment of both acute and chronic viral infections. These drugs inhibit viral replication due to one or more distinct mechanisms. It modifies the virus's genetic structure by reducing viral capacity in every replication cycle. Their clinical success has shown strong effectiveness against several viruses, including ebolavirus, hepatitis C virus, HIV, MERS, SARS-Cov, and the most recent emergent SARS-Cov2. In this review, seven different types of inhibitors have been selected that show broad-spectrum activity against RNA viruses. A detailed overview and mechanism of actionof both analogues are given, and the clinical perspectives are discussed. These inhibitors incorporated the novel SARS-CoV-2 RdRp, further terminating the polymerase activity with variable efficacy. The recent study provides a molecular basis for the inhibitory activity of virus RdRp using nucleotide and nucleoside analogues inhibitors. Furthermore, to identify those drugs that need more research and development to combat novel infections. Consequently, there is a pressing need to focus on present drugs by establishing their cell cultures. If their potencies were evidenced, then they would be explored in the future as potential therapeutics for novel outbreaks.

Proximal tubular dysfunction related to tenofovir in people living with HIV/AIDS: a pharmacogenetic study

OBJECTIVES

The purpose of this case-control study was to verify the association between single nucleotide polymorphisms (SNPs) in genes encoding drug transporters related to tenofovir disoproxil fumarate (TDF) and proximal renal tubular dysfunction (PRTD), and the association between PRTD and clinical characteristics.

METHODS

The 'cases' met the diagnostic criteria for PRTD, determined by the presence of two or more of the following abnormalities: non-diabetic glycosuria, metabolic acidosis, increased uric acid and phosphorus excretion, decreased tubular phosphorus reabsorption and β2-microglobulinuria. We analyzed eight SNPs in ABCC2, ABCC4, ABCC10 and SLC28A2 genes. Genotyping was performed using real-time PCR.

RESULTS

Of the 204 people living with HIV, 38 (18.6%) met the criteria for diagnosis of PRTD and 131 were male (64.2%), with a mean age of 49 years and a history of previous antiretroviral therapy for an average of 5 years. In the multivariate analysis, older individuals, TDF use, protease inhibitor, antihypertensives and anticonvulsants were associated with a risk of developing PRTD. Increased excretion of β2microglobulin was associated with the A/G genotype of rsCC8187710 from ABCC2 ( P  = 0.003) and the following genotypes of ABCC4 SNPs: A/G from rs1059751 ( P  = 0.023), G/G from rs1059751 ( P  = 0.030) and C/C of rs3742106 ( P  = 0.041). The increase in the fraction of excreted phosphorus was associated with the C/T genotype of SNCC rsP40037 from ABCC2 ( P  = 0.0041).

CONCLUSIONS

The results indicate an important relationship between SNPs associated with these markers and changes in proximal renal tubule function, and thus support their use as biomarkers for the early detection of PRTD risk.

Short-term oral pre-exposure prophylaxis against HIV-1 modulates the transcriptome of foreskin tissue in young men in Africa

Whilst short-term oral pre-exposure prophylaxis (PrEP) with antiretroviral drugs in men who have sex with men has shown protection against HIV-1 infection, the impact of this regimen on the in vivo foreskin transcriptome is unknown. We collected foreskin tissue after voluntary medical male circumcision from 144 young men (72 from Uganda and 72 from South Africa) randomized to one to two doses of either oral tenofovir (TFV) disoproxil fumarate (FTC-TDF) or tenofovir alafenamide (FTC-TAF) or no drug (untreated controls). This novel approach allowed us to examine the impact of short-term oral PrEP on transcriptome of the male genital tract. A single dose of FTC-TDF did not affect the foreskin transcriptome in relation to control arm, however one dose of FTC-TAF induced upregulation of four genes AKAP8, KIAA0141, HSCB and METTL17. Following two doses of either FTC-TDF or FTC-TAF, there was an increase in 34 differentially expressed genes for FTC-TDF and 15 for FTC-TAF, with nine DEGs in common: KIAA0141, SAFB2, CACTIN, FXR2, AKAP8, HSCB, CLNS1A, DDX27 and DCAF15. Functional analysis of differentially expressed genes revealed modulation of biological processes related to mitochondrial stress (KIAA0141, HSCB and METTL17), anti-viral and anti-inflammatory pathways (CACTIN and AKAP8). Our results show that short-course on-demand oral PrEP in men modulates genes in foreskin tissue which are likely unfavorable to HIV acquisition and replication. We also describe an upregulated expression of genes involved in diverse mitochondria biology which may potentially result in worsened mitochondria-related. These results warrant further studies to assess the role of short-course and prolonged oral PrEP on biological processes of the foreskin mucosa.

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.

Risk Factors of Renal Tubular Dysfunction in Thai People Living with HIV Receiving Tenofovir Disoproxil Fumarate

Tenofovir disoproxil fumarate (TDF) associates with renal tubular dysfunction (RTD) in some people living with HIV (PLWH). We studied clinical and genetic factors associated with RTD in Thai PLWH receiving TDF. RTD was diagnosed in 13 of 65 (20%) patients. The median (interquartile range) age and CD4 cell counts were 43.8 (40.4-50.9) years and 554 (437-716) cells/mm³, respectively. The median duration of TDF use was 46.9 (31.5-54.1) months. Univariate logistic regression demonstrated body mass index (BMI), concomitant use of protease inhibitor (PI), hyperlipidemia, and homozygous C/C SNP rs1059751 of ABCC4 gene as predisposing factors of RTD. In multivariate model, concomitant use of PI [adjusted odds ratio (aOR) 11.39; 95% confidence interval (CI), 1.59- 81.56; P = 0.015], hyperlipidemia (aOR 8.59; 95% CI, 1.46-50.40; P = 0.017), and BMI (aOR 0.76; 95% CI, 0.59-0.98; P = 0.037) remained associated with RTD in patients receiving TDF. PLWH receiving TDF with the presence of these factors should be closely monitored for RTD.

Impact of tenofovir on SARS-CoV-2 infection and severe outcomes among people living with HIV: a propensity score-matched study

BACKGROUND

Reports on the impact of some antiretrovirals against SARS-CoV-2 infection and disease severity are conflicting.

OBJECTIVES

We evaluated the effect of tenofovir as either tenofovir alafenamide/emtricitabine (TAF/FTC) or tenofovir disoproxil fumarate/emtricitabine (TDF/FTC) against SARS-CoV-2 infection and associated clinical outcomes among people living with HIV (PLWH).

METHODS

We conducted a propensity score-matched analysis in the prospective PISCIS cohort of PLWH (n = 14 978) in Catalonia, Spain. We used adjusted Cox regression models to assess the association between tenofovir and SARS-CoV-2 outcomes.

RESULTS

After propensity score-matching, SARS-CoV-2 diagnosis rates were similar in TAF/FTC versus ABC/3TC recipients (11.6% versus 12.5%, P = 0.256); lower among TDF/FTC versus ABC/3TC recipients (9.6% versus 12.8%, P = 0.021); and lower among TDF/FTC versus TAF/FTC recipients (9.6% versus 12.1%, P = 0.012). In well-adjusted logistic regression models, TAF/FTC was no longer associated with reduced SARS-CoV-2 diagnosis [adjusted odds ratio (aOR) 0.90; 95% confidence interval (CI), 0.78-1.04] or hospitalization (aOR 0.93; 95% CI, 0.60-1.43). When compared with ABC/3TC, TDF/FTC was not associated with reduced SARS-CoV-2 diagnosis (aOR 0.79; 95% CI, 0.60-1.04) or hospitalization (aOR 0.51; 95% CI, 0.15-1.70). TDF/FTC was not associated with reduced SARS-CoV-2 diagnosis (aOR 0.79; 95% CI, 0.60-1.04) or associated hospitalization (aOR 0.33; 95% CI, 0.10-1.07) compared with TAF/FTC.

CONCLUSIONS

TAF/FTC or TDF/FTC were not associated with reduced SARS-CoV-2 diagnosis rates or associated hospitalizations among PLWH. TDF/FTC users had baseline characteristics intrinsically associated with more benign SARS-CoV-2 infection outcomes. Tenofovir exposure should not modify any preventive or therapeutic SARS-CoV-2 infection management.

Pradefovir Treatment in Patients With Chronic Hepatitis B: Week 24 Results From a Multicenter, Double-Blind, Randomized, Noninferiority, Phase 2 Trial

BACKGROUND

Pradefovir is a liver-targeted prodrug of adefovir, a nucleoside/nucleotide analogue with antiviral activity against hepatitis B virus (HBV) DNA polymerase. This phase 2 study compared the efficacy and safety of oral pradefovir (30, 45, 60, or 75 mg) versus tenofovir disoproxil fumarate (TDF; 300 mg) and aimed to identify the most appropriate dose of pradefovir for the forthcoming phase 3 study.

METHODS

Treatment-naive and experienced (not on treatment >6 months) patients with chronic hepatitis B were eligible.

RESULTS

A total of 240 participants were randomized and treated in the study (48 per group). Approximately 80% were hepatitis B e antigen (HBeAg) positive, and 10% had liver cirrhosis. The reductions from baseline in HBV DNA levels achieved at week 24 were 5.40, 5.34, 5.33, and 5.40 log10 IU/mL, with pradefovir doses of 30-, 45-, 60-, and 75-mg, respectively, compared with 5.12 log10 IU/mL with TDF. However, HBeAg loss was attained by more participants who received 45-, 60-, or 75-mg pradefovir than by those receiving TDF (12%, 6%, and 9% vs 3%). The TDF group exhibited a more significant increase in serum creatinine than the pradefovir 30- and 45-mg groups, and serum phosphate levels were comparable among all groups. Most adverse events (AEs) were mild (grade 1). No treatment-related severe AEs were reported. Overall, AEs and laboratory abnormalities were comparable to those in the TDF group.

CONCLUSIONS

Pradefovir and TDF exhibited comparable reductions in HBV DNA levels. All treatments were safe and well tolerated.

CLINICAL TRIALS REGISTRATION

NCT00230503 and China Drug Trials CTR2018042.

Renal safety of tenofovir disoproxil fumarate and entecavir in liver transplant patients: a nationwide Korean registry study

BACKGROUND AND AIMS

Tenofovir disoproxil fumarate (TDF) and entecavir (ETV) have been recommended after liver transplantation to prevent recurrence of hepatitis B virus infection. Despite its proven efficacy, the renal safety of TDF has not been established in liver transplant recipients. We aimed to compare the effects of TDF and ETV on renal function in liver transplant recipients and to evaluate risk factors for renal dysfunction after liver transplantation.

METHODS

This is a retrospective, observational multicenter study of data from the Korean Organ Transplantation Registry. We included adults who underwent liver transplantation for hepatitis B virus-related complications from April 2014 to December 2017 and received TDF or ETV post-transplantation. Renal dysfunction was defined as an estimated glomerular filtration rate decline by at least 20% from baseline (1 month post-transplantation). Median duration of follow-up was 29 months (interquartile range 19-42).

RESULTS

A total of 804 liver transplant patients were included. The cumulative probability of renal dysfunction was significantly higher in the TDF group than in the ETV group. Multivariable analysis confirmed that TDF was independently associated with an increased risk of renal dysfunction (hazard ratio = 1.47, 95% confidence interval 1.12-1.92; p = 0.005). Independent risk factors for renal dysfunction included older age, worse baseline renal function, and low body mass index. Overall survival rate was significantly lower in patients with renal dysfunction than in those without.

CONCLUSIONS

In this nationwide study, the use of TDF was associated with an increased risk of renal dysfunction, when compared with ETV.

Fanconi syndrome in a patient receiving pre-exposure prophylaxis for HIV infection: case report

BACKGROUND

Tenofovir disoproxil is efficacious in the preventing HIV infection as part of a pre-exposure prophylaxis (PrEP) regimen. Although its use has been associated with impaired renal function, instances of Fanconi syndrome are extremely rare. This may change with increased uptake of PrEP.

METHODS

A 55-year-old male patient (he/him/his) was commenced on PrEP with a baseline estimated glomerular filtration rate (eGFR) of approximately 60mL/min/1.73m2.

RESULTS

Within 6months, he developed new and worsening proteinuria, glycosuria and aminoaciduria despite no apparent change in eGFR. PrEP was discontinued and his urinary abnormalities rapidly resolved. The patient remains off PrEP.

CONCLUSIONS

Fanconi syndrome is a rare, but known complication of tenofovir disoproxil. This is the first report related to PrEP in Australia. While tenofovir associated nephrotoxicity in patients taking PrEP is uncommon, the patient's age and pre-existing renal impairment placed him at substantially higher risk. At-risk patients need more frequent monitoring of their eGFR and proteinuria. Urinary protein to creatinine ratio is the preferred to dipstick testing for proteinuria and the latter does not readily detect the low molecular wight proteinuria characteristic of tenofovir toxicity. Early recognition of these patients is essential, as prompt cessation of PrEP can often reverse renal abnormalities.

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.

HIV: the changing paradigm

The past four decades have seen enormous progress in the diagnosis and management of human immunodeficiency virus (HIV) infection. There have been significant advances spanning the approval of the first antiretroviral agents, the advent of combination antiretroviral therapy to single tablet regimens with minimal toxicity. Although these remarkable developments have on the surface led to the 'end of AIDS', there are still key populations being left behind. This clinical update will describe the diagnosis and management of HIV, and the changing paradigms that have seen HIV transform from a life-limiting condition to a manageable chronic disease over a few decades.

Dolutegravir/rilpivirine 2-drug regimen comparable to commonly prescribed 3-drug regimens up to 18-months in a real-world setting

Background

This study compared the effectiveness and durability of DTG/RPV with commonly prescribed 3-drug regimens (3-DR) in people living with HIV (PLWH) in a real-world setting.

Methods

Antiretroviral therapy (ART)-experienced, virologically suppressed PLWH who initiated DTG/RPV or a 3-DR in 2018 were identified in the OPERA® database and followed through 6/30/2019. Virologic failure (two consecutive viral loads (VL) ≥ 200 copies/mL or single VL ≥ 200 copies/mL with regimen modification/discontinuation) and maintained virologic suppression (last VL test < 50 or < 200 copies/mL) were described. Kaplan–Meier methods were used to estimate time to virologic failure and treatment discontinuation. Risk of virologic failure was adjusted for age, sex, race/ethnicity, risk of infection, region, baseline CD4 cell count, history of substance abuse or syphilis, and mortality risk score at baseline in a Cox model.

Results

PLWH initiating DTG/RPV were older and more likely to be Hispanic or have comorbidities than 3-DR initiators. DTG/RPV users experienced fewer discontinuations (15%) and were more likely to be suppressed at study end (98%) than 3-DR users (28% and 96%, respectively). Virologic failure was uncommon; rates per 100 person-years did not differ between the DTG/RPV (1.45, 95% CI: 0.69, 3.03) and 3-DR (2.63, 95% CI: 2.21, 3.14) groups. The risk of virologic failure did not differ significantly between the groups in adjusted Cox models (adjusted hazard ratio 1.32, 95% CI: 0.61, 2.89).

Conclusions

The findings of this real-world OPERA® study suggest that DTG/RPV can be a viable alternative to standard 3-DRs for ART-experienced, virologically suppressed PLWH.

Glucocorticoid-Induced Hypokalemic Periodic Paralysis after Short-Term Use of Tenofovir with Hypophosphatemia: A Case Report

Hypokalemic periodic paralysis (HPP) is a neuromuscular disorder associated with muscular dysfunction caused by hypokalemia. There are various causes of HPPs and rarely, HPP appears to be relevant to tenofovir or glucocorticoid treatment. There have been several case reports of tenofovir-related nephrotoxicity or tenofovir-induced HPP. However, a case report of glucocorticoid-induced HPP in a patient using tenofovir temporarily has not been reported. Herein, we report a case of glucocorticoid-induced HPP with short-term use of tenofovir. A 28-year-old man visited the emergency room with decreased muscle power in all extremities (2/5 grade). In their past medical history, the patient was treated with tenofovir for two months for a hepatitis B virus infection. At the time of the visit, the drug had been discontinued for four months. The day before visiting the emergency room, betamethasone was administered at a local clinic for herpes on the lips. Laboratory tests showed hypokalemia, hypophosphatemia, and mild metabolic acidosis. However, urinalysis revealed no abnormal findings. Consequently, it can be postulated that this patient developed HPP by glucocorticoids after taking tenofovir temporarily. This is the first case report of glucocorticoid-induced HPP in a patient using tenofovir. Clinicians who prescribe tenofovir should be aware of HPP occurring when glucocorticoids are used.

Tenofovir alafenamide treatment may not worsen the lipid profile of chronic hepatitis B patients: a propensity score-matched analysis

Background/Aims

Tenofovir alafenamide (TAF) has shown less favorable effect on lipids compared to tenofovir disoproxil fumarate (TDF) in clinical trials. However, data regarding these outcomes in patients with chronic hepatitis B (CHB) are scarce. Therefore, this study aimed to evaluate the effect of TAF on the lipid in patients with CHB.

Methods

A total of 237 TAF-treated CHB patients compared with TDF, inactive CHB, and non-hepatitis B virus (HBV)-infected control groups using propensity score matching (PSM).

Results

Following PSM, each analysis was conducted on cohorts via the matching of 70:140 (TAF:TDF), 89:89 (TAF:inactive CHB), 140:560 (TAF:non-HBV infected control), and 368:1,472 (TDF:non-HBV-infected control). A significant decrease in the total cholesterol (TC) level was noted at 48 weeks in the TDF group compared to the TAF group (176.3±32.9 vs. 156.7±27.7, P<0.001) and the non-HBV-infected control group (175.0±29.5 vs. 156.2±28.3, P<0.001). However, no significant change in TC was observed in the TAF group and inactive CHB or non-HBV-infected control groups at 48 weeks. For the subgroup analyses of TAF vs. non-HBV-infected control subjects and inactive CHB patients whose detailed lipid profile information were available, no between-group differences in TC, low-density lipoprotein (LDL)-cholesterol, highdensity lipoprotein (HDL)-cholesterol, TC/HDL ratio, and LDL/HDL ratio were observed at 48 weeks.

Conclusions

TDF seems to have a lipid-lowering effect compared to the non-HBV-infected control and TAF-treated groups. However, in real practice, TAF might not worsen the lipid profiles of subjects compared to non-HBV-infected controls and patients with inactive CHB.

Renal function in Japanese HIV-1-positive patients who switch to tenofovir alafenamide fumarate after long-term tenofovir disoproxil fumarate: a single-center observational study

BACKGROUND

Tenofovir disoproxil fumarate (TDF) has a strong antiviral effect, but TDF is known to cause renal dysfunction. Therefore, we are investigating preventing renal dysfunction by replacing TDF with tenofovir alafenamide fumarate (TAF), which is known to be relatively safe to the kidneys. However, the changes in renal function under long-term use of TAF are not known. In this study, we evaluated renal function in Japanese HIV-1-positive patients switching to TAF after long-term treatment with TDF.

METHODS

A single-center observational study was conducted in Japanese HIV-1-positive patients. TDF was switched to TAF after at least 48 weeks of the treatment so we could evaluate the long-term use of TDF. The primary endpoint was the estimated glomerular filtration rate (eGFR) at 144 weeks of TAF administration. In addition, we predicted the factors that would lead to changes in eGFR after long-term use of TAF.

RESULTS

Of the 125 HIV-1-positive patients who were prescribed TAF at our hospital during the study period, 70 fulfilled the study criteria. The eGFR at the time of switching from TDF to TAF was 81.4 ± 21.1 mL/min/1.73 m2. eGFR improved significantly after 12 weeks of taking TAF but significantly decreased at 96 and 144 weeks. The factors significantly correlated with the decrease in eGFR at 144 weeks on TAF were eGFR and weight at the start of TAF.

CONCLUSIONS

In this study, it was confirmed that switching to TAF was effective for Japanese HIV-1-positive patients who had been taking TDF for a long period of time and had a reduced eGFR. It was also found that the transition status depended on the eGFR and weight at the time of switch. Since HIV-1-positive patients in Japan are expected to continue taking TAF for a long time, renal function and body weight should be carefully monitored.

Comparison of Renal Function Between Tenofovir Disoproxil Fumarate and Other Nucleos(t)ide Reverse Transcriptase Inhibitors in Patients With Hepatitis B Virus Infection

Background

Nucleoside and nucleotide reverse transcriptase inhibitors (NRTIs) have become a standard treatment for both HIV and hepatitis B virus (HBV) infections. Tenofovir disoproxil fumarate (TDF) has been associated with kidney injury and possible long-term damage in patients with HIV. Few studies have examined whether this holds true for patients treated for HBV.

Methods

Data were gathered from the Veterans Health Administration Corporate Data Warehouse between July 1, 2005 and July 31, 2015. Patients aged ≥ 18 years with HBV infection and prescribed a NRTI for > 1 month were included in the study and followed for 36 months. Patients with HIV infection were excluded, and patients treated with combination TDF/emtricitabine were analyzed separately from patients receiving only TDF. A linear mixed model was used to examine the effects of time and specific agent on renal function, which was measured with estimated glomerular filtration rate (eGFR) at various time intervals.

Results

There were 413 incidences of NRTI use in 308 subjects during the 10 years of the study with 39 cases of TDF use. There was a significant fixed effect of time, with eGFR reduction of 4.6 mL/min (P < .001) over the course of the study for the full cohort, but the effects of each medication were not significant.

Conclusions

This multicenter, retrospective study did not demonstrate an association between TDF use and a greater degree of kidney injury compared with other NRTIs in patients with HBV, but further studies are warranted.

Hepatitis B Virus Infection in Pregnancy: An Update on Evidence-Based Management

Importance

Vertical hepatitis B virus (HBV) transmission is the important route of chronic HBV infection. Although infant immunoprophylaxis is effective, a significant number of infants still become infected, most are associated with intrauterine infection. New evidences support intrauterine treatment in cases of high risk.

Objective

The aim of this study was to review the current evidences and recommendations for management of HBV infection in pregnancy.

Evidence Acquisition

Original research articles, review articles, and guidelines were reviewed.

Results

The management can be summarized as follows: (1) all pregnant women should be screened for hepatitis B surface antigen (HBsAg) and antibody to HBsAg. High-risk HBsAg-negative pregnant women without immunity should be vaccinated during pregnancy. (2) HBsAg-positive pregnant women should undergo further workup for liver status and indicative factors for immunoprophylaxis failure. (3) Pregnant women should be treated with HBV DNA levels greater than 200,000 IU/mL or 6 log copies/mL. (4) Antiviral drug should be started around 28 to 32 weeks. The first-line drug is tenofovir disoproxil fumarate. (5) Delivery route should be chosen based only on obstetric indications. (6) Breastfeeding is not contraindicated because it does not increase the risk of transmission in neonates with HBV vaccine and immunoglobulin administration. (7) Neonates born to HBsAg-positive mothers should receive HBV vaccine and immunoglobulin after birth as soon as possible. (8) Follow-up of the mothers and neonates is important. Beware of hepatitis flare after birth and after antiretroviral drug discontinuation; alanine transaminase assessment every 1 to 3 months until 6 months is suggested. Also, the schedule of infant vaccination and follow-up of serologic testing at 9 to 12 months old is needed.

Pharmacokinetics and renal safety of tenofovir alafenamide with boosted protease inhibitors and ledipasvir/sofosbuvir

BACKGROUND

Ledipasvir/sofosbuvir increases tenofovir plasma exposures by up to 98% with tenofovir disoproxil fumarate (TDF), and exposures are highest with boosted PIs. There are currently no data on the combined use of the newer tenofovir prodrug, tenofovir alafenamide (TAF), boosted PIs and ledipasvir/sofosbuvir.

OBJECTIVES

To compare the plasma and intracellular pharmacokinetics and renal safety of TAF with ledipasvir/sofosbuvir when co-administered with boosted PIs.

METHODS

Persons with HIV between 18 and 70 years and on a boosted PI with TDF were eligible. The study was comprised of four phases: (1) TDF 300 mg with boosted PI; (2) TAF 25 mg with boosted PI; (3) TAF 25 mg with boosted PI and ledipasvir/sofosbuvir; and (4) TAF 25 mg with boosted PI. Pharmacokinetic sampling, urine biomarker collection [urine protein (UPCR), retinol binding protein (RBP) and β2 microglobulin (β2M) normalized to creatinine] and safety assessments occurred at the end of each phase. Plasma, PBMCs and dried blood spots were collected at each visit.

RESULTS

Ten participants were enrolled. Plasma tenofovir exposures were 76% lower and tenofovir-diphosphate (TFV-DP) concentrations in PBMCs increased 9.9-fold following the switch to TAF. Neither of these measures significantly increased with ledipasvir/sofosbuvir co-administration, nor did TAF plasma concentrations. No significant changes in estimated glomerular filtration rate or UPCR occurred, but RBP:creatinine and β2M:creatinine improved following the switch to TAF.

CONCLUSIONS

Ledipasvir/sofosbuvir did not significantly increase plasma tenofovir or intracellular TFV-DP in PBMCs with TAF. These findings provide reassurance that the combination of TAF, boosted PIs and ledipasvir/sofosbuvir is safe in HIV/HCV-coinfected populations.

Population pharmacokinetics and pharmacogenetics of ritonavir-boosted darunavir in the presence of raltegravir or tenofovir disoproxil fumarate/emtricitabine in HIV-infected adults and the relationship with virological response: a sub-study of the NEAT001/ANRS143 randomized trial

OBJECTIVES

NEAT001/ANRS143 demonstrated non-inferiority of once-daily darunavir/ritonavir (800/100 mg) + twice-daily raltegravir (400 mg) versus darunavir/ritonavir + tenofovir disoproxil fumarate/emtricitabine (245/200 mg once daily) in treatment-naive patients. We investigated the population pharmacokinetics of darunavir, ritonavir, tenofovir and emtricitabine and relationships with demographics, genetic polymorphisms and virological failure.

METHODS

Non-linear mixed-effects models (NONMEM v. 7.3) were applied to determine pharmacokinetic parameters and assess demographic covariates and relationships with SNPs (SLCO3A1, SLCO1B1, NR1I2, NR1I3, CYP3A5*3, CYP3A4*22, ABCC2, ABCC10, ABCG2 and SCL47A1). The relationship between model-predicted darunavir AUC0-24 and C24 with time to virological failure was evaluated by Cox regression.

RESULTS

Of 805 enrolled, 716, 720, 347 and 361 were included in the darunavir, ritonavir, tenofovir and emtricitabine models, respectively (11% female, 83% Caucasian). No significant effect of patient demographics or SNPs was observed for darunavir or tenofovir apparent oral clearance (CL/F); coadministration of raltegravir did not influence darunavir or ritonavir CL/F. Ritonavir CL/F decreased by 23% in NR1I2 63396C>T carriers and emtricitabine CL/F was linearly associated with creatinine clearance (P<0.001). No significant relationship was demonstrated between darunavir AUC0-24 or C24 and time to virological failure [HR (95% CI): 2.28 (0.53-9.80), P=0.269; and 1.82 (0.61-5.41), P=0.279, respectively].

CONCLUSIONS

Darunavir concentrations were unaltered in the presence of raltegravir and not associated with virological failure. Polymorphisms investigated had little impact on study-drug pharmacokinetics. Darunavir/ritonavir + raltegravir may be an appropriate option for patients experiencing NRTI-associated toxicity.

Impact of switching to TAF/FTC/RPV, TAF/FTC/EVG/cobi and ABC/3TC/DTG on cardiovascular risk and lipid profile in people living with HIV: a retrospective cohort study

BACKGROUND

We aimed to assess the overall cardiovascular and metabolic effect of the switch to three different single tablet regimens (STRs) [tenofovir alafenamide/emtricitabine/rilpivirine (TAF/FTC/RPV), TAF/FTC/elvitegravir/cobi (TAF/FTC/EVG/cobi) and ABC/lamivudine/dolutegravir (ABC/3TC/DTG)] in a cohort of people living with HIV/AIDS (PLWH) under effective ART.

METHODS

All PLWH aged above 18 years on antiretroviral treatment with an HIV-RNA < 50 cp/mL at the time of the switch to TAF/FTC/RPV, TAF/FTC/EVG/cobi and ABC/3TC/DTG were retrospectively included in the analysis. Framingham risk score modification after 12 months from the switch such as lipid profile and body weight modification were assessed. The change from baseline to 12 months in mean cardiovascular risk and body weight in each of the STR's group were assessed by means of Wilcoxon signed-rank test whereas a mixed regression model was used to assess variation in lipid levels.

RESULTS

Five-hundred and sixty PLWH were switched to an STR regimen of whom 170 (30.4%) to TAF/FTC/EVG/cobi, 191 (34.1%) to TAF/FTC/RPV and 199 (35.5%) to ABC/3TC/DTG. No difference in the Framingham cardiovascular risk score was observed after 12 months from the switch in each of the STR's groups. No significant overtime variation in mean total cholesterol levels from baseline to 12 months was observed for PLWH switched to ABC/3TC/DTG [200 (SD 38) mg/dl vs 201 (SD 35) mg/dl; p = 0.610] whereas a significant increment was observed in PLWH switched to TAF/FTC/EVG/cobi [192 (SD 34) mg/dl vs 208 (SD 40) mg/dl; p < 0.0001] and TAF/FTC/RPV [187 (SD 34) mg/dl vs 195 (SD 35) mg/dl; p = 0.027]. In addition, a significant variation in the mean body weight from baseline to 12 months was observed in PLWH switched to TAF/FTC/EVG/cobi [72.2 (SD 13.5) kilograms vs 74.6 (SD 14.3) kilograms; p < 0.0001] and TAF/FTC/RPV [73.4 (SD 11.6) kilograms vs 75.6 (SD 11.8) kilograms; p < 0.0001] whereas no difference was observed in those switched to ABC/3TC/DTG [71.5 (SD 12.8) kilograms vs 72.1 (SD 12.6) kilograms; p = 0.478].

CONCLUSION

No difference in the cardiovascular risk after 1 year from the switch to these STRs were observed. PLWH switched to TAF/FTC/EVG/cobi and TAF/FTC/RPV showed an increase in total cholesterol levels and body weight 12 months after the switch.

Bioequivalence Evaluation of Two Formulations of Tenofovir Alafenamide Tablets in Healthy Subjects Under Fasting and Fed Conditions

Purpose

To evaluate the bioequivalence and safety of two formulations of 25 mg tenofovir alafenamide tablets in Chinese healthy male and female subjects under fed and fasting conditions.

Patients and Methods

This was a randomized, open-label, single-center, crossover study consisting of a fasting trial with two periods and a fed trial with four periods. In total, 42 healthy subjects were enrolled in the fasting trial and 32 healthy subjects were enrolled in the fed trial. In each period, blood samples for pharmacokinetic analysis were collected until 72 hours post-dose. The plasma concentrations of tenofovir alafenamide and tenofovir were measured and noncompartmental analysis was used to determine pharmacokinetic parameters. Throughout the entire study, subjects' safety was monitored by assessment of physical examinations, vital signs, 12-lead electrocardiography, clinical laboratory parameters, and treatment emergent adverse events (TEAEs).

Results

Forty subjects completed the fasting trial and 32 subjects completed the fed trial. The 90% confidence intervals (CIs) of the geometric mean ratios for AUC_0-t, AUC_0-∞, and C_max for the two formulations were within 80.00% to 125.00%, which met the bioequivalence acceptance criteria. The study drugs were well tolerated by all subjects.

Conclusion

This study demonstrated that the test formulation of 25 mg tenofovir alafenamide tablets was bioequivalent to the formulation marketed under the brand name VEMLIDY^® in healthy Chinese male and female subjects under fasting and fed conditions.

Comparative safety review of recommended, first-line single-tablet regimens in patients with HIV

Introduction Different single-tablet regimens (STRs), containing one or two nucleoside reverse transcriptase inhibitors (NRTIs) plus an anchor drug, are available for the use in naïve, HIV-infected patients. Despite some restrictions in the use of particular regimens in certain situations (e.g., HBV coinfection), International guidelines do not provide indications to prefer any regimen over others concerning the tolerability profile. We aimed to assess advantages and disadvantages of the most prescribed STRs.Areas covered An extensive review of articles published in English language was conducted on PubMed, looking for evidence about STRs in naïve, HIV-infected population. Safety outcomes of registrational trials were assessed, giving priority to studies directly comparing STRs included in our research (abacavir/lamivudine/dolutegravir, tenofovir alafenamide/emtricitabine/bictegravir, lamivudine/dolutegravir, tenofovir alafenamide/emtricitabine/darunavir/cobicistat, tenovofir disoproxil fumarate/lamivudine/doravirine). Data from cohort studies and meta-analyses were also assessed, extrapolating the main evidence about the combinations of interest.Expert opinion Integrase inhibitors (InsTIs)-based regimens have few interruptions for adverse events and few drug-related adverse events, with tenofovir alafenamide/emtricitabine/dolutegravir and lamivudine/dolutegravir being the most tolerable ones. However, neuropsychiatric adverse events and metabolic issues could prompt the alternative use of darunavir or doravirine-based combinations, even if a superior safety profile of these combinations over InSTIs has yet to be demonstrated.

Renal Phosphate Handling in Antiretroviral-naive HIV-Infected Patients

BACKGROUND

Human immunodeficiency virus (HIV) infection impairs renal function, thereby affecting renal phosphate metabolism.

OBJECTIVES

We prospectively estimated the prevalence of phosphate abnormalities (mild, moderate to life-threatening hypophosphataemia, and hyperphosphataemia) before initiating antiretroviral therapy (ART).

METHODS

A cross-sectional analysis was performed on 170 consecutive newly diagnosed ARTnaive, HIV-infected patients attending our HIV/AIDS clinics over a period of one year. Fifty (50) screened HIV-negative blood donors were used for comparison (controls). Blood and urine were collected simultaneously for phosphate and creatinine assay to estimate fractional phosphate excretion (FEPi %) and glomerular filtration rate (eGFR).

RESULTS

eGFR showed significant difference between patients' and controls' medians (47.89ml/ min/1.73m2 versus 60ml/min/1.73m2, p <0.001); which denotes a moderate chronic kidney disease in the patients. Of the 170 patients, 78 (45.9%) had normal plasma phosphate (0.6-1.4 mmol/L); 85 (50%) had hyperphosphataemia. Grades 1, 2 and 3 hypophosphataemia was observed in 3 (1.8%), 3 (1.8%), and 1(0.5%) patient(s) respectively. None had grade 4 hypophosphataemia. Overall, the patients had significantly higher median of plasma phosphate than the controls, 1.4 mmol/L (IQR: 1.0 - 2.2) versus 1.1 mmol/L (IQR: 0.3 - 1.6), p <0.001, implying hyperphosphataemia in the patients; significantly lower median urine phosphate than the controls, 1.5 mmol/L (IQR: 0.7 -2.1) versus 8.4 mmol/L (IQR: 3.4 - 16), p <0.001), justifying the hyperphosphataemia is from phosphate retention; but a non-significantly lower median FEPi% than the controls, 0.96% (IQR: 0.3 -2.2) versus 1.4% (IQR: 1.2 -1.6), p > 0.05. Predictors of FEPi% were age (Odds ratio, OR 0.9, p = 0.009); weight (OR 2.0, p < 0.001); CD4+ cells count predicted urine phosphate among males (p = 0.029).

CONCLUSION

HIV infection likely induces renal insufficiency with reduced renal phosphate clearance. Thus, hyperphosphataemia is highly prevalent, and there is mild to moderate hypophosphataemia but its life-threatening form (grade 4) is rare among ART-naive HIV patients.

Tenofovir Disoproxil Fumarate-Associated Renal Dysfunction Among Adult People Living with HIV at the University of Gondar Comprehensive Specialized Hospital, Northwest Ethiopia, 2019: A Comparative Retrospective Cohort Study

BACKGROUND

The use of tenofovir disoproxil fumarate (TDF) has been reported to be a significant contributor to renal dysfunction. However, patients in Ethiopia may be different than in other parts of the world, and findings from such studies may not apply in this setting.

OBJECTIVE

This study aimed to assess TDF-associated renal dysfunction among adult people living with HIV (PLHIV) at the University of Gondar Comprehensive Specialized Hospital, Northwest Ethiopia.

METHODS

This retrospective cohort study included adult PLHIV between January 2015 and June 2019. The Chronic Kidney Disease Epidemiology (CKD-EPI) equation was used to estimate glomerular filtration rate (eGFR). Renal dysfunction was defined as eGFR <60 mL/min/1.73 m2. Data were entered into Epi Info™ 7 and analyzed by using SPSS® software version 20. The Kaplan-Meier method was used to estimate the survival curves. Cox proportional hazards models were used to identify predictors of renal dysfunction using a 95% confidence interval and p-value ≤ 0.05 as a statistical significance.

RESULTS

Out of 400 participants, 200 were TDF-based ART groups, and 200 were non-TDF-based ART groups. The incidence of renal dysfunction of TDF and the non-TDF group was 28.31 per 100 person-years (PYs) and 12.53 per 100 PYs, respectively. Adult PLHIV taking TDF-based regimens were 1.70 (adjusted HR = 1.70; 95% CI = 1.02-2.82) times at higher risk of renal dysfunction than non-TDF-based regimens. Age ≥55, diabetes mellitus, concurrent nephrotoxic drug use, and combined use of ritonavir-boosted protease inhibitors were also associated significantly with renal dysfunction.

CONCLUSION

The incidence rate of renal dysfunction among TDF users is higher than non-TDF users. Exposure to TDF is a significant risk of renal dysfunction in adult PLHIV. Clinicians should regularly monitor the renal function of adult PLHIV who are taking TDF.

A novel evidence of serial changes of bone mineral density in chronic hepatitis B patients treated with entecavir

BACKGROUND AND AIMS

Tenofovir disoproxil fumarate (TDF) and Entecavir (ETV) are commonly used for patients with chronic hepatitis B (CHB), and renal or bone toxicity are possible concerns. This study is to evaluate the renal and bone effect of TDF compared with ETV in CHB patients.

METHODS

This is a retrospective study at Kaohsiung Chung-Gung memorial hospital, Taiwan, from June 2013 to December 2018. Patients with CHB were prescribed with TDF or ETV for 3 years or above. Renal function was assessed at 12-week intervals. Dual-energy X-ray absorptiometry scans of the spine and femurs were performed at 48-week intervals. The propensity score analysis was conducted to balance the baseline characteristics of patients in both treatment groups.

RESULTS

A total of 258 patients were included in this study: TDF (n = 135) and ETV (n = 123). The prevalence of osteopenia was much higher in the TDF group at week 48 and week 96. The TDF group showed significant mean percentage decrease from baseline in bone mineral density throughout the treatment course. Logistic regression analysis adjusted for the propensity score demonstrated that the use of TDF was the only predictive factor of significant bone density loss at week 144. The mean percentage decline of estimated glomerular filtration rate was significant in the TDF group at all time points. Renal threshold phosphate concentration was similar among both treatment groups.

CONCLUSIONS

This study suggested CHB patients treated with TDF may experience increased risks of bone loss and renal deficits compared to those treated with ETV.

Cerebral Vascular Toxicity of Antiretroviral Therapy

HIV infection is associated with comorbidities that are likely to be driven not only by HIV itself, but also by the toxicity of long-term use of antiretroviral therapy (ART). Indeed, increasing evidence demonstrates that the antiretroviral drugs used for HIV treatment have toxic effects resulting in various cellular and tissue pathologies. The blood-brain barrier (BBB) is a modulated anatomophysiological interface which separates and controls substance exchange between the blood and the brain parenchyma; therefore, it is particularly exposed to ART-induced toxicity. Balancing the health risks and gains of ART has to be considered in order to maximize the positive effects of therapy. The current review discusses the cerebrovascular toxicity of ART, with the focus on mitochondrial dysfunction. Graphical Abstract Graphical representation of the interactions between HIV, antiretroviral therapy (ART), and the blood-brain barrier (BBB).

Long-term Nucleotide Analogue Treatment Has Higher Levels of Renal Toxicities than Does Entecavir in Patients with Chronic Hepatitis B

Background/Aims

Renal toxicity is a concern in patients with chronic hepatitis B taking nucleotide analogues, such as adefovir (ADV) and tenofovir disoproxil fumarate (TDF). We sought to determine the long-term renal effects of nucleotide analogue treatment versus entecavir (ETV) treatment.

Methods

In this retrospective single-center study, we selected 87 patients who were treated with ADV and subsequently with TDF from June 2008 to December 2013. ETV-treated patients were matched by treatment duration. We analyzed the creatinine increase over 0.5 mg/dL, glomerular filtration rate (GFR) decrease over 25%, phosphorus decrease under 2.0 mg/dL, and dose reduction of antiviral agents.

Results

The median follow-up period was 60.0 months for both groups. The incidence of liver cirrhosis was higher in the ADV-TDF group than in the ETV group (32.2% vs 74.7%, p<0.01). Creatinine increased in both groups during follow-up, but the difference was not significant (5.7% and 2.3%, p=0.44). In addition, GFR decreased more often in the ADV-TDF group than in the ETV group (31.0% and 14.9%, p=0.01). After multivariate Cox regression analysis, ADV-TDF treatment was significantly associated with a GFR decrease over 25% (hazard ratio, 2.10; 95% confidence interval, 1.08 to 4.10; p=0.03) after adjusting for the baseline GFR decrease.

Conclusions

Patients taking nucleotide analogues had a significantly higher number of renal events than did those taking ETV. Clinicians should be aware of the development of renal toxicity in this patient population. Further long-term studies are warranted.

Associations Between Tenofovir Diphosphate in Dried Blood Spots, Impaired Physical Function, and Fracture Risk

BACKGROUND

In this study, we evaluate associations between cumulative antiretroviral adherence/exposure, quantified using tenofovir diphosphate (TFV-DP) in dried blood spots (DBS), and human immunodeficiency virus (HIV)-related aging factors.

METHODS

This is a cross-sectional analysis of younger (ages 18-35) and older (ages ≥60) persons with HIV (PWH) taking TFV disoproxil fumarate. Tenofovir diphosphate concentrations were quantified in DBS. Linear and logistic regression models were used to evaluate associations between TFV-DP and bone mineral density (BMD), physical function, frailty, and falls.

RESULTS

Forty-five PWH were enrolled (23 younger, 22 older). Every 500 fmol/punch (equivalent to an increase in ~2 doses/week) increase in TFV-DP was associated with decreased hip BMD (-0.021 g/cm2; 95% confidence interval [CI], -0.040 to -0.002; P = .03). Adjusting for total fat mass, every 500 fmol/punch increase in TFV-DP was associated with higher odds of Short Physical Performance Battery impairment (score ≤10; adjusted odds ratio [OR], 1.6; 95% CI, 1.0-2.5; P = .04). Every 500 fmol/punch increase in TFV-DP was associated with slower 400-meter walk time (14.8 seconds; 95% CI, 3.8-25.8; P = .01) and remained significant after adjusting for age, lean body mass, body mass index (BMI), and fat mass (all P ≤ .01). Every 500 fmol/punch increase in TFV-DP was associated with higher odds of reporting a fall in the prior 6 months (OR, 1.8; 95% CI, 1.1-2.8; P = .02); this remained significant after adjusting for age, lean body mass, BMI, and total fat mass (all P < .05).

CONCLUSIONS

Higher TFV-DP levels were associated with lower hip BMD, poorer physical function, and greater risk for falls, a concerning combination for increased fracture risk.

Cardiovascular Events in an Inner-City HIV Clinic and Relationship to Abacavir Versus Tenofovir Disoproxil Fumarate-Containing Antiretroviral Regimens

Following cardiovascular events (CVE) among people living with HIV (PLWH) is essential. Abacavir (ABC)'s impact on CVE challenges clinicians. We characterized CVE at our HIV clinic associated with ABC versus tenofovir disoproxil fumarate (TDF). This was a retrospective study of PLWH who started combination antiretroviral therapy with no prior CVE. Patients were evaluated as antiretroviral naive or antiretroviral experienced. Regimens included the following: always-ABC, always-TDF, first-ABC-switched-to-TDF, and first-TDF-switched-to-ABC regimens. Frequencies, rates, and Poisson regression were used to analyze CVE (cardiovascular/cerebrovascular) and were stratified with an a priori cutoff of before or after January 1, 2009. 1,440/2,852 patients were antiretroviral naive; 658 on always-ABC regimens, 1,186 on always-TDF regimens, 737 first-ABC-switched-to-TDF regimens, and 271 first-TDF-switched-to-ABC regimens. Seventy seven CVE occurred overall [16 naive vs. 61 experienced (p < .0001)]. Sixty events were cardiovascular and 17 cerebrovascular (p < .0001). Sixty-nine CVE occurred before 2009 and eight after (p < .0001). There were 5.65 CVE-per-1,000-years [95% confidence interval (CI) 3.23-9.87] in the always-ABC, 1.95 CVE-per-1,000-years (95% CI 1.08-3.51) in the always-TDF, 2.01 CVE-per-1,000-years (95% CI 1.14-3.56) in the ABC-switched-to-TDF, and 1.82 CVE-per-1,000-years (95% CI 0.77-4.30) in TDF-switched-to-ABC (p <.01). Multivariable Poisson regression incidence rate ratios (IRRs) revealed that being on ABC-only (IRR 2.89; 95% CI 2.13-3.94), age (IRR 1.06 per year; 95% CI 1.04-1.07), and smoking (IRR for current 2.81; 95% CI 1.97-3.99; IRR for former 2.49; 95% CI 1.72-3.61) increased risk of CVE. Thus, in our clinic, CVE rates were increased in those on ABC and adds to the body of literature suggesting concern.

Effect of Human Immunodeficiency Virus on Trace Elements in the Brain

Comorbidities of human immunodeficiency virus (HIV) include HIV-associated neurocognitive disorder (HAND). Changes in the brain due to HIV include atrophy, hyperintensities, and diffusion changes. However, no research has focused on trace elements concentration changes in the brain due to HIV, as seen in other neurodegenerative diseases. Therefore, the aim of this study was to determine the concentration of several trace elements in the brains of individuals with and without HIV infection. Prior to formalin embalming, blood was drawn and tested in triplicate with Determine HIV-1/2 rapid tests and confirmed with a SD HIV Device 1/2 3.0 rapid HIV Kit. After embalming, tissue was sampled from the caudate nucleus and analyzed using inductively coupled plasma mass spectrometry. A Kruskal-Wallis test was used to determine statistically significant differences between the two groups (p < 0.05). Fifteen HIV-positive and 14 HIV-negative male cadavers were included (mean age 44, range 22 to 61). Cadmium was marginally decreased, possibly due to malnutrition or utilization by the HIV nucleocapsid. Nickel was marginally increased, perhaps due to a reduced capability to remove metals from the body. In conclusion, this article provides the first information on trace element levels in the brains from HIV-infected individuals and postulates that cadmium and nickel may play a role in the pathophysiology of HAND. This information can contribute to finding a treatment for HAND, other than the use of antiretroviral drugs. Future studies should asses the levels of cadmium and nickel in a larger cohort of HIV-infected individuals.

Application of High-Performance Liquid Chromatography for Simultaneous Determination of Tenofovir and Creatinine in Human Urine and Plasma Samples

Tenofovir disoproxil fumarate is widely used in the therapy of human immunodeficiency virus and hepatitis B virus; however, a high concentration of the prodrug effects kidney function damage. To control the effectiveness of kidney functions in treated patients, the level of creatinine in the body must be controlled. This work describes a simple, fast, and “plastic-waste” reducing method for the simultaneous determination of tenofovir and creatinine in human urine and plasma. In both assays, only 50 µL of body fluid was required. The tests were carried out by reversed phase high-performance liquid chromatography with UV detection. In urine samples, the limits of detection for tenofovir and creatinine were 4 µg mL⁻¹ and 0.03 µmol mL⁻¹, respectively. In plasma samples, the limits of detection were 0.15 µg mL⁻¹ for tenofovir and 0.0003 µmol mL⁻¹ for creatinine. The method was applied for the determination of tenofovir and creatinine in human urine and plasma samples. The biggest advantage of the elaborated method is the possibility to determine tenofovir and creatinine in one analytical run in both urine and plasma sample collected from HIV and HBV patients. The possibility to reduce the level of laboratory waste in a sample preparation protocol is in the mainstream of a new trend of analytical chemistry which is based on green chemistry.

Melatonin protects against tenofovir-induced nephrotoxicity in rats by targeting multiple cellular pathways

Nephrotoxicity is a dose-limiting side effect of long-term use of tenofovir, a reverse transcriptase inhibitor that is used for the treatment of HIV infection and chronic hepatitis B infection. Identifying an agent that prevents tenofovir disoproxil fumarate (TDF)-induced renal injury can lead to its better tolerance, and a more effective treatment can be achieved. The present study is aimed at investigating whether melatonin, a potent antioxidant and anti-inflammatory agent, protects against TDF nephrotoxicity in rats and to determine its cellular targets. Rats were divided into groups and treated as follows. Group I (control): Rats in this group (n = 6) received sterile water only by gavage for 35 days. Group II: Rats (n = 6) in this group received 600 mg/kg body weight TDF in sterile water by gavage for 35 days. Group III: Rats (n = 6) in this group received once daily 20 mg/kg bodyweight melatonin i.p. 2 h before the administration of 600 mg/kg body weight TDF in sterile water by gavage for 35 days. Group IV: Rats were pretreated daily with 20 mg/kg body weight melatonin i.p. 2 h before the administration of sterile water by gavage. All the rats were sacrificed on the 36th day, after overnight fast. Melatonin pretreatment protected the rats against TDF nephrotoxicity both histologically and biochemically. Biochemically, melatonin pretreatment attenuated TDF-induced, oxidative stress, nitrosative stress, mitochondrial pathway of apoptosis, PARP overactivation and preserved proximal tubular function (p < 0.01). This suggests that melatonin may be useful in ameliorating TDF nephrotoxicity.