Tenofovir nephrotoxicity among Asians living with HIV: review of the literature

Urinary α 1-microglobulin and β 2-microglobulin as markers of early kidney injury in HIV-positive male patients on tenofovir-based antiretroviral therapy

BACKGROUND

A retrospective study was conducted to explore the urinary expression of α 1-microglobulin (α1MG) and β2-microglobulin (β2MG) in patients with human immunodeficiency virus (HIV) infection, aiming to evaluate their predictive capability for renal injury.

METHOD

One hundred and five male HIV-infected patients treated with Tenofovir (TDF) regimen (TDF+3TC or the third drug TDF/FTC+) were selected between March 1, 2021, and March 1, 2022, in Wuhan Jinyintan Hospital. Three months after TDF treatment, the renal function injury was evaluated with the standard creatinine clearance rate. The urinary levels of α1MG and β2MG were compared between the initiation of TDF treatment and three months thereafter. Spearman correlation was utilized to analyze the correlation between the urinary expression of α1MG and β2MG and renal injury in HIV patients. The logistic regression was used to analyze the predictive value of urinary α1MG and β 2-microglobulin expression in renal injury.

RESULTS

Up to the first follow-up, 29 (27.6%) cases of the 105 male HIV patients had varying degrees of renal function injury, including 14 (13.3%) mild injury, 9 (8.6%) moderate injury, and 6 (5.7%) severe injury cases. Patients with severe renal injury had the highest levels of urinary α1MG and β2MG expression while those with mild injury demonstrated higher levels compared to the non-injury group (P < 0.05). Spearman correlation analysis indicated that urinary α1MG and β2MG were positively correlated with renal impairment in HIV patients (Rho = -0.568, and -0.732; P < 0.001). The ROC curve analysis demonstrated that the area under the curve (AUC) for urine α1MG and β2MG in predicting kidney damage among HIV patients were 0.928, 0.916, and 0.889, respectively. The sensitivity values were 96.55%, 82.76%, and 89.66% while the specificity values were 84.07%, 94.51%, and 89.29% for urine α1MG and β2MG, respectively.

CONCLUSION

The expression level of urinary α1MG and β2MG in HIV patients was significantly higher compared to normal people. Detection of these two indexes can enable early determination of renal injury and its severity in HIV patients.

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

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

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

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

What is the role of microbial biotechnology and genetic engineering in medicine?

Microbial products are essential for developing various therapeutic agents, including antibiotics, anticancer drugs, vaccines, and therapeutic enzymes. Genetic engineering techniques, functional genomics, and synthetic biology unlock previously uncharacterized natural products. This review highlights major advances in microbial biotechnology, focusing on gene-based technologies for medical applications.

Current practice and recommendations for management of hepatitis B virus in people living with HIV in Asia

BACKGROUND

The prevalence of HIV and hepatitis B virus (HBV) co-infection is higher in Asia than in Europe and North America and varies significantly between different regions within Asia. Important routes of transmission of both these infections include high-risk unprotected sexual contact, intravenous drug use, and transmission of maternal infection perinatally or in early childhood. While life expectancy among people living with HIV has been extended with effective antiretroviral therapy (ART), HBV-induced liver injury and complications have emerged as a leading cause of morbidity and mortality in people living with HIV.

OBJECTIVES

This article describes the prevalence of co-infection, current clinical practice, and recommendations for the management of people living with HIV-HBV co-infection in Asia.

RESULTS AND CONCLUSIONS

Screening for HBV should occur at the time of HIV diagnosis; however, HBV screening rates in people living with HIV in Asia vary widely by region. Similarly, people with HBV should be screened for HIV before initiation of HBV antiviral therapy. People with HIV-HBV co-infection should be assessed for liver damage and risk factors for liver disease and be monitored regularly for liver complications and HBV DNA. Medical treatment with ART is lifelong and includes tenofovir and lamivudine or emtricitabine, unless intolerant or contraindicated, as these are active against both HIV and HBV. HBV vaccination programmes are effective in reducing co-infection rates. Mother-to-child transmission can be prevented through measures such as vaccination, antenatal screening, and treatment of pregnant women who are infected.

Tenofovir-Induced Renal Dysfunction Among HIV-Infected Patients: A Systematic Review

Tenofovir disoproxil fumarate (TDF) is an antiretroviral drug widely used as part of antiretroviral therapy (ART) to treat human immunodeficiency virus (HIV-1) infection. Negative effects of tenofovir include impaired kidney function, especially with long-term use. In studies conducted among HIV-positive individuals, we found evidence of extensive kidney damage associated with TDF use. Despite the therapeutic importance of this consequence, its continued use in ART regimens was not contraindicated. The therapeutic and long-term effects of TDF are a major concern. However, in countries or settings where resources are limited and renal function monitoring cannot be ensured, screening methods to detect ART-related renal failure are still supported by data. Therefore, it is safe to re-evaluate the use of TDF-based ART. However, adherence to guidelines may be hampered by insufficient laboratory testing in low- and middle-income countries. More research is also needed among people under 18 years of age and pregnant and breastfeeding mothers.

3D Spheroids of Human Primary Urine-Derived Stem Cells in the Assessment of Drug-Induced Mitochondrial Toxicity

Mitochondrial toxicity (Mito-Tox) risk has increased due to the administration of several classes of drugs, particularly some life-long antiretroviral drugs for HIV+ individuals. However, no suitable in vitro assays are available to test long-term Mito-Tox (≥4 weeks). The goal of this study is to develop a 3D spheroid system of human primary urine-derived stem cells (USC) for the prediction of drug-induced delayed Mito-Tox. The cytotoxicity and Mito-Tox were assessed in 3D USC spheroids 4 weeks after treatment with antiretroviral drugs: zalcitabine (ddC; 0.1, 1 and 10 µM), tenofovir (TFV; 3, 30 and 300 µM) or Raltegravir (RAL; 2, 20 and 200 µM). Rotenone (RTNN, 10 µM) and 0.1% DMSO served as positive and negative controls. Despite only mild cytotoxicity, ddC significantly inhibited the expression of oxidative phosphorylation enzyme Complexes I, III, and IV; and RAL transiently reduced the level of Complex IV. A significant increase in caspase 3 and ROS/RNS level but a decrease in total ATP were observed in USC treated with ddC, TFV, RAL, and RTNN. Levels of mtDNA content and mitochondrial mass were decreased in ddC but minimally or not in TFV- and RAL-treated spheroids. Thus, 3D USC spheroid using antiretroviral drugs as a model offers an alternative platform to assess drug-induced late Mito-Tox.

A metabolic modeling approach reveals promising therapeutic targets and antiviral drugs to combat COVID-19

In this study we have developed a method based on Flux Balance Analysis to identify human metabolic enzymes which can be targeted for therapeutic intervention against COVID-19. A literature search was carried out in order to identify suitable inhibitors of these enzymes, which were confirmed by docking calculations. In total, 10 targets and 12 bioactive molecules have been predicted. Among the most promising molecules we identified Triacsin C, which inhibits ACSL3, and which has been shown to be very effective against different viruses, including positive-sense single-stranded RNA viruses. Similarly, we also identified the drug Celgosivir, which has been successfully tested in cells infected with different types of viruses such as Dengue, Zika, Hepatitis C and Influenza. Finally, other drugs targeting enzymes of lipid metabolism, carbohydrate metabolism or protein palmitoylation (such as Propylthiouracil, 2-Bromopalmitate, Lipofermata, Tunicamycin, Benzyl Isothiocyanate, Tipifarnib and Lonafarnib) are also proposed.