Low Risk of Proximal Tubular Dysfunction Associated With Emtricitabine-Tenofovir Disoproxil Fumarate Preexposure Prophylaxis in Men and Women

Brief Report: Incidence and Management of Complex Kidney Situations Among On-Demand and Daily HIV Pre-Exposure Prophylaxis Users

BACKGROUND

We evaluated complex pre-exposure prophylaxis (PrEP) situations linked to kidney issues in a cohort of on-demand and daily PrEP users.

SETTING

We conducted a single-center retrospective cohort study in France including all PrEP users who received a tenofovir disoproxil (TD)-emtricitabine (FTC) prescription between January 1, 2012 and December 31, 2019 with at least 1 creatinine measurement available before and after PrEP initiation.

METHODS

A complex kidney situation (CKS) was defined as an estimated glomerular filtration rate (eGFR) <60 mL/minute/1.73m 2 on 2 consecutive measurements. We estimated the incidence of this event, described case management, and identified associated factors using a Cox model.

RESULTS

Three thousand one hundred and fourteen individuals were included in this study. Almost all were men (99%) with a median age of 35 years, 25% had an eGFR <90 mL/minute/1.73m 2 at baseline, and 65% used on-demand PrEP. Nine users (0.29%) had a CKS at baseline; 8/9 initiated on-demand PrEP without renal function worsening after a median (interquartile range [IQR]) follow-up time of 14 months (7-31). Thirteen cases of CKS occurred during the follow-up for a 0.25 per 100 person-years incidence (95% confidence interval [CI]: [0.14; 0.45]). On-demand PrEP was used in 7/13 participants with no further episode of confirmed eGFR <60 mL/minute/1.73m 2 after a 17-month median follow-up (IQR 4-18). CKS was associated with an age ≥50 years (hazard ratio [HR] 13, 95% CI: [4-39]) or with a baseline eGFR <90 mL/minute/1.73m 2 (HR 34, 95% CI: [4-261]). 9/22 CKS were linked to high-protein intake for weight training.

CONCLUSIONS

CKS were rare in our cohort. On-demand PrEP did not result in subsequent renal function worsening in these few situations.

Effect of anti-retroviral regimen on proximal tubular function in Zambian adolescents and young adults living with HIV: A cross sectional study

Background: Tenofovir regimens remain the preferred formulations in the HIV guidelines for adolescents and young adults in Zambia and globally. However, some adolescents and young adults are maintained on abacavir by clinicians because of anxiety about possible proximal tubular dysfunction from tenofovir. We assessed the effect of two regimens on proximal tubular function in adolescents and young adults living with HIV. Methods: This was a cross-sectional study involving 180 participants with HIV receiving either tenofovir or abacavir for ≥12 months at the largest tertiary teaching hospital. Two first-morning urine and blood specimens were collected and analyzed for proximal tubular markers, glomerular function, electrolytes, and routine monitoring tests. Proximal tubular function was determined by measuring the fractional excretion of phosphate (FePO4). Proximal tubular dysfunction was defined by FePO4 ≥20% regardless of serum phosphate and FePO4  ≥10-20% when serum phosphate was below 0.81mmol/L. Results: The prevalence of proximal tubular dysfunction was 6% and was higher in the tenofovir group than the abacavir (10% vs. 2%, p<0.058). However, after adjusting for potential confounders, tenofovir was not associated with worse proximal tubular function. Age, urine b2-microglobulin: creatinine ratio, C-reactive protein, and urine protein: creatinine ratio was all associated with worsening proximal tubular dysfunction. Reduced estimated glomelurar filtration rate (eGFR) was found in four (2.2%) participants; three of which were on tenofovir. Conclusions: Proximal tubular dysfunction defined by FePO4 was more prevalent in the tenofovir group than the abacavir group, but not after adjusting for age. Our findings should be interpreted with caution as age differences between the two groups confounded the results.

Impact on renal function of daily and on-demand HIV pre-exposure prophylaxis in the ANRS-PREVENIR study

OBJECTIVES

To assess the impact on the estimated glomerular filtration rate (eGFR) of different tenofovir disoproxil/emtricitabine dosing regimens for HIV pre-exposure prophylaxis (PrEP).

PATIENTS AND METHODS

We included in the study individuals with baseline eGFR > 50 mL/min/1.73 m2 who initiated PrEP in the ongoing ANRS-PREVENIR PrEP cohort. We retrospectively classified PrEP users in three groups: 'on-demand' (reported at ≥75% of study visits), 'daily' (≥75% of study visits) or 'switches'. We compared the area under curve (AUC) of the eGFR variation from baseline (ΔeGFR) between groups using analysis of covariance, and assessed factors associated with a negative AUC of ΔeGFR.

RESULTS

From May 2017 to October 2020, 1253 PrEP-naïve participants (98% of MSM) were included in the study with a median follow-up of 22 months. 499 (40%), 494 (39%) and 260 (21%) users were in the group daily, on-demand and switches, respectively, for a median number of pills taken per week of 6, 1.7 and 4. The mean AUC of the ΔeGFR was -1.09 mL/min/1.73 m2 in the daily PrEP group, -0.69 mL/min/1.73 m2 in the switches group and +0.18 mL/min/1.73 m2 with on-demand PrEP. In a model adjusted on baseline age and eGFR, the AUC of the ΔeGFR was significantly higher with on-demand PrEP compared to daily PrEP (P = 0.037). Independent factors associated with a negative AUC of ΔeGFR were a daily PrEP regimen, a switches regimen, an age > 40 years and a baseline eGFR≥90 mL/min/1.73 m².

CONCLUSIONS

On-demand PrEP dosing had a smaller impact on eGFR evolution than daily PrEP, but the difference was not clinically relevant.

HIV at 40: kidney disease in HIV treatment, prevention, and cure

Four decades after the first cases of HIV were reported, kidney disease remains an important comorbidity in people with HIV (PWH). Both HIV-associated nephropathy and immune complex kidney disease were recognized as complications of HIV infection in the early years before treatment was available. Although the introduction of effective antiretroviral therapy in the late 1990s resulted in dramatic improvements in survival and health in PWH, several commonly used antiretroviral agents have been associated with kidney injury. HIV infection and treatment may also promote the progression of comorbid chronic kidney disease due to traditional risk factors such as diabetes, and HIV is one of the strongest "second hits" for the high-risk APOL1 genotype. Unique considerations in the management of chronic kidney disease in PWH are largely related to the need for lifelong antiretroviral therapy, with potential for toxicity, drug-drug interactions, and polypharmacy. PWH who develop progressive chronic kidney disease are candidates for all modalities of kidney replacement therapy, including kidney transplantation, and at some centers, PWH may be candidates to serve as donors for recipients with HIV. Transplantation of kidney allografts from donors with HIV also offers a unique opportunity to study viral dynamics in the kidney, with implications for kidney health and for research toward HIV cure. In addition, HIV-transgenic animal models have provided important insights into kidney disease pathogenesis beyond HIV, and experience with HIV and HIV-related kidney disease has provided important lessons for future pandemics.

Safety of oral tenofovir disoproxil - emtricitabine for HIV preexposure prophylaxis in adults

PURPOSE OF REVIEW

This review focuses on the safety of oral tenofovir disoproxil and emtricitabine (FTC) combination for HIV preexposure prophylaxis (PrEP) in adults.

RECENT FINDINGS

Gastrointestinal adverse events are common after treatment initiation but usually resolve within weeks. Although clinical trials did not report an increased risk of serious renal adverse events or tubulopathy, meta-analyses suggest that tenofovir disoproxil -FTC is associated with a slight but non-clinically relevant decline in estimated glomerular filtration rate (eGFR). A decline to less than 60 mL/min remains a rare event, which mainly occurs in users with an age >50 years or a baseline creatinine clearance < 90 mL/min. Similarly, a slight reduction in bone mineral density (BMD) was observed in clinical trials, but it did not result in an increased risk of bone fracture. BMD reduction and eGFR decline tend to resolve after treatment discontinuation. No drug interaction with contraception has been reported in women and no safety signal emerged in pregnant and breastfeeding women.

SUMMARY

Oral tenofovir disoproxil-FTC for HIV PrEP appears safe and well tolerated for most individuals. This supports demedicalization strategies aiming at increasing the number of PrEP users.

Kidney function in tenofovir disoproxil fumarate-based oral pre-exposure prophylaxis users: a systematic review and meta-analysis of published literature and a multi-country meta-analysis of individual participant data

BACKGROUND

Previous WHO guidance on tenofovir disoproxil fumarate-based oral pre-exposure prophylaxis (PrEP) suggests measuring creatinine levels at PrEP initiation and regularly afterwards, which might represent barriers to PrEP implementation and uptake. We aimed to systematically review published literature on kidney toxicity among tenofovir disoproxil fumarate-based oral PrEP users and conducted an individual participant data meta-analysis (IPDMA) on kidney function among PrEP users in a global implementation project dataset.

METHODS

In this systematic review and meta-analysis we searched PubMed up to June 30, 2021, for randomised controlled trials (RCTs) or cohort studies that reported on graded kidney-related adverse events among oral PrEP users (tenofovir disoproxil fumarate-based PrEP alone or in combination with emtricitabine or lamivudine). We extracted summary data and conducted meta-analyses with random-effects models to estimate relative risks of grade 1 and higher and grade 2 and higher kidney-related adverse events, measured by elevated serum creatinine or decline in estimated creatinine clearance or estimated glomerular filtration rate. The IPDMA included (largely unpublished) individual participant data from 17 PrEP implementation projects and two RCTs. Estimated baseline creatinine clearance and creatinine clearance change after initiation were described by age, gender, and comorbidities. We used random-effects regressions to estimate the risk in decline of creatinine clearance to less than 60 mL/min.

FINDINGS

We identified 62 unique records and included 17 articles reporting on 11 RCTs with 13 523 participants in meta-analyses. PrEP use was associated with increased risk of grade 1 and higher kidney adverse events (pooled odds ratio [OR] 1·49, 95% CI 1·22-1·81; I2=25%) and grade 2 and higher events (OR 1·75, 0·68-4·49; I2=0%), although the grade 2 and higher association was not statistically significant and events were rare (13 out of 6764 in the intervention group vs six out of 6782 in the control group). The IPDMA included 18 676 individuals from 15 countries (1453 [7·8%] from RCTs) and 79 (0·42%) had a baseline estimated creatinine clearance of less than 60 mL/min (increasing proportions with increasing age). Longitudinal analyses included 14 368 PrEP users and 349 (2·43%) individuals had a decline to less than 60 mL/min creatinine clearance, with higher risks associated with increasing age and baseline creatinine clearance of 60·00-89·99 mL/min (adjusted hazard ratio [aHR] 8·49, 95% CI 6·44-11·20) and less than 60 mL/min (aHR 20·83, 12·83-33·82).

INTERPRETATION

RCTs suggest that risks of kidney-related adverse events among tenofovir disoproxil fumarate-based oral PrEP users are increased but generally mild and small. Our global PrEP user analysis found varying risks by age and baseline creatinine clearance. Kidney function screening and monitoring might focus on older individuals, those with baseline creatinine clearance of less than 90 mL/min, and those with kidney-related comorbidities. Less frequent or optional screening among younger individuals without kidney-related comorbidities may reduce barriers to PrEP implementation and use.

FUNDING

Unitaid, Bill & Melinda Gates Foundation, WHO.

Kidney function and daily emtricitabine/tenofovir disoproxil fumarate pre-exposure prophylaxis against HIV: results from the real-life multicentric demonstrative project PrEP Brazil

Background

Pre-Exposure Prophylaxis (PrEP) has demonstrated efficacy in the reduction of sexually transmitted HIV infections. The prolonged use of tenofovir disoproxil fumarate (TDF) and emtricitabine (FTC) co-formulation (TDF/FTC), however, may result in augmented risk of renal toxicity. We aimed to evaluate changes in the estimated Glomerular Filtration Rate (eGFR) in a real-world population setting of participants enrolled in PrEP Brazil, a 48-week prospective, open-label, demonstration study to assess the feasibility of daily oral TDF/FTC used by men who have sex with men and transgender women at high-risk of HIV infection, all over 18 years old.

Methods

Kidney function was assessed by serial measurement of serum creatinine and eGFR with the Modification of Diet in Renal Disease Study (MDRD) formula on weeks 4, 12, 24, 36 and 48. Adherence to PrEP was assessed by dosing TDF concentration in dried blood spots at weeks 4 and 48, measured by liquid chromatography-mass spectrometry or mass spectrometry.

Results

Of 392 participants completing the 48-week follow-up protocol with TDF blood detectable levels and eGFR measures, 43.1% were young adults, of Caucasian ethnic background (57.9%), with BMI below 30 kg/m², without arterial hypertension. At screening, median eGFR was 93.0 mL/min/1.73 m². At week 4 follow-up, 90 (23% of the study population) participants presented reductions in eGFR greater than 10 mL/min/1.73 m² as compared to baseline eGFR, some as large as 59 mL/min/1.73 m², but with no clinical outcomes (adverse events and renal adverse events) severe enough to demand TDF/FTC discontinuation. A negative relationship was observed between TDF blood levels and eGFR at weeks 4 (r = − 0.005; p < 0.01) and 48 (r = − 0.006; p < 0.01).

Conclusions

These results suggest that the renal function profile in individuals on TDF/FTC may be assessed on week 4 and then only annually, allowing a more flexible medical follow-up in primary care centers.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12981-022-00437-4.

Proximal tubular dysfunction in pregnant women receiving tenofovir disoproxil fumarate to prevent mother-to-child transmission of hepatitis B virus

BACKGROUND

Data evaluating the risk of proximal tubular dysfunction in women receiving tenofovir disoproxil fumarate for the prevention of mother-to-child transmission (PMTCT) of HBV are scarce.

OBJECTIVES

To assess the risk of proximal tubulopathy in pregnant women receiving tenofovir disoproxil fumarate for PMTCT of HBV.

PATIENTS AND METHODS

We used urine samples collected from HBV monoinfected pregnant women who participated in a Phase III, multicentre, randomized, double-blind, placebo-controlled clinical trial assessing a tenofovir disoproxil fumarate short course from 28 weeks gestational age (28-wk-GA) to 2 months post-partum (2-months-PP) for PMTCT of HBV in Thailand. Markers of tubular dysfunction, including retinol binding protein, kidney injury molecule-1, α1-microglobuin and β2-microglobulin, were assayed at 28- and 32-wk-GA and 2-months-PP visits. Proximal tubulopathy was defined as the presence of ≥2 of the following: tubular proteinuria, euglycaemic glycosuria and increased urinary phosphate.

RESULTS

A total of 291 women participated in the study. No kidney-related adverse events were severe, and none led to tenofovir disoproxil fumarate discontinuation. At 2-months-PP, 3 of the 120 (3%) evaluated women in the tenofovir disoproxil fumarate group experienced proximal tubulopathy versus 3 of 125 (2%) in the placebo group (P  = 1.00). None of the six women met the criteria for proximal tubulopathy at 12-months-PP but proteinuria persisted in three of them. No growth abnormalities were found at 1 year of age in infants born to mothers with proximal tubulopathy at 2-months-PP.

CONCLUSIONS

In these HBV-infected pregnant and breastfeeding women, tenofovir disoproxil fumarate administered from 28-wk-GA to 2-months-PP was not associated with a higher risk of proximal tubulopathy.

Integrating PrEP delivery in public health family planning clinics: a protocol for a pragmatic stepped wedge cluster randomized trial in Kenya

Background

Adolescent girls and young women account for a disproportionate fraction of new HIV infections in Africa and are a priority population for HIV prevention, including provision of pre-exposure prophylaxis (PrEP). Anchoring PrEP delivery to care settings like family planning (FP) services that women already access routinely may offer an efficient platform to reach HIV at-risk women. However, context-specific implementation science evaluation is needed.

Methods

The Family Planning Plus Project is a prospective, pragmatic implementation evaluation, designed as a stepped wedge, cluster randomized trial, at 12 clinics in Kenya. In collaboration with the Kenya Ministry of Health and Kisumu County Department of Health, we will introduce integration of HIV risk screening and PrEP delivery in public health FP clinics. The core multifaceted implementation strategies to integrate PrEP in FP clinics will include: (1) PrEP delivery by existing FP clinic staff, (2) health provider training, (3) PrEP technical assistance to coach and mentor providers, (4) joint supervision with Kisumu County health officials, and (5) stakeholder engagement. All core components of PrEP delivery—including screening for HIV risk, HIV testing, dispensing, adherence and risk reduction counseling, assessment of side effects, and provision of refills, or safety assessment—will be conducted by existing FP clinic staff as part of a standard care service package. The goal is to catalyze sustainable scale-up within existing infrastructures beyond the project. We will rigorously evaluate implementation outcomes and impact, using the RE-AIM (Reach, Effectiveness, Adoption, Implementation, Maintenance) framework, and we will use Organizational Readiness for Implementing Change (ORIC) and the Consolidated Framework for Implementation Science Research (CFIR) to assess readiness to implement and contextual enablers and barriers of implementation, including how clinics innovate efficient delivery systems.

Discussion

Anchoring PrEP delivery to existing FP systems and staffing has tremendous potential to address barriers that women face in accessing HIV prevention and PrEP care, including lack of time, cost, and stigma of visiting a facility solely for HIV prevention. The FP Plus Project will initiate preparation for full-scale and sustainable model of integration of comprehensive HIV prevention services, including PrEP implementation, in public health FP clinics in low-income settings.

Trial registration

Registered with ClinicalTrials.gov on December 14, 2020: NCT04666792

Renal impairment in a large-scale HIV preexposure prophylaxis implementation cohort

BACKGROUND

HIV preexposure prophylaxis (PrEP) with fixed-dose tenofovir disoproxil fumarate (TDF) and emtricitabine has been associated with low rates of renal impairment in clinical trials. Large-scale PrEP implementation may result in higher rates, as the prevalence of associated risk factors may be higher than in trial populations.

METHODS

A posthoc analysis of EPIC-NSW, a large Australian multicentre PrEP implementation trial for patients at high risk of HIV infection. Participants were eligible for inclusion if they commenced PrEP between 1 March 2016 and 30 April 2018, and had renal function assessed at baseline and at least once more before the censor date. The primary outcome was new-onset renal impairment, defined as an estimated glomerular filtration rate (eGFR) <60 ml/min per 1.73 m2.

RESULTS

A total of 6808 participants were eligible for inclusion. Almost all were male (99%), with a median age of 35 years [interquartile range (IQR): 28-44]. Approximately one-quarter (26%) had a baseline eGFR <90 ml/min per 1.73 m2. Over a median follow-up period of 1.2 years (IQR: 0.6-1.7), the rate of renal impairment was 5.8 episodes per 1000 person-years [95% confidence interval (CI): 4.0-7.8]. In multivariable Cox regression, there was a higher risk of renal impairment in participants aged ≥50 years [hazard ratio (HR) 14.7, 95% CI: 5.0-43.3, P < 0.001] and those with an eGFR <90 ml/min per 1.73 m2 (HR 28.9, 95% CI: 6.9-121.9) at baseline.

CONCLUSION

In a large-scale implementation study, TDF-containing PrEP was associated with a low risk of renal impairment overall, whereas older patients and those with preexisting renal dysfunction were at substantially increased risk.

Mechanisms of Proteinuria in HIV

Proteinuria is common in the setting of HIV infection, and may reflect comorbid kidney disease, treatment-related nephrotoxicity, and HIV-related glomerular diseases. The mechanisms of podocyte and tubulointerstial injury in HIV-associated nephropathy (HIVAN) have been the subject of intense investigation over the past four decades. The pathologic contributions of viral gene expression, dysregulated innate immune signaling, and ancestry-driven genetic risk modifiers have been explored in sophisticated cellular and whole animal models of disease. These studies provide evidence that injury-induced podocyte dedifferentiation, hyperplasia, cytoskeletal dysregulation, and apoptosis may cause the loss of glomerular filtration barrier integrity and slit diaphragm performance that facilitates proteinuria and tuft collapse in HIVAN. Although the incidence of HIVAN has declined with the introduction of antiretroviral therapy, the collapsing FSGS lesion has been observed in the context of other viral infections and chronic autoimmune disorders, and with the use of interferon-based therapies in genetically susceptible populations. This highlights the fact that the lesion is not specific to HIVAN and that the role of the immune system in aggravating podocyte injury warrants further exploration. This review will summarize our progress in characterizing the molecular mechanisms of podocyte dysfunction in HIVAN and other forms of HIV-associated kidney disease.

HIV pre-exposure prophylaxis and sexually transmitted infections: intersection and opportunity

Pre-exposure prophylaxis (PrEP) has revolutionized HIV prevention, but PrEP does not protect against other sexually transmitted infections (STIs). Rates of STIs are rising worldwide, with notably high incidences among PrEP-using men who have sex with men in high-income countries; in low-income and middle-income countries, data are sparse, but results from a limited number of studies among African women initiating and taking PrEP have shown high STI prevalence and incidence. Efforts aimed at markedly reducing HIV in populations worldwide include a major focus on increasing PrEP use, along with improving HIV testing and treatment in order to eliminate HIV transmission. Together, these efforts could augment continued expansion of the global STI epidemic, but they could alternatively create an opportunity to improve STI control, including the development of comprehensive sexual health programmes and research to develop new STI prevention strategies. The introduction of PrEP globally has been characterized by challenges and many successes, and its role as part of a range of robust strategies to reduce HIV infections is clear. Looking ahead, understanding rising rates of curable STIs and their relationship to HIV prevention, and considering the future directions for synergies in PrEP and STI prevention will be integral to improving sexual health.

Fanconi Syndrome Induced by Concomitant HIV PrEP and Tacrolimus

Fanconi syndrome (FS) is a severe grade of drug-induced proximal tubule toxicity. There are numerous causes for acquired FS, and drug toxicity is one of the most common. FS is known to be associated with the nucleoside reverse transcriptase inhibitor (NRTI) tenofovir disoproxil fumarate (TDF). TDF is often used in combination with emtricitabine (FTC) for preexposure prophylaxis (PrEP) of human immunodeficiency virus (HIV) infection. TDF/FTC-induced FS has been observed as a dose-related phenomenon that is directly correlated to kidney function, high levels of absorption of the drug into the proximal tubule, and interactions with other medications. This case report describes a patient who acquired FS after starting TDF/FTC for PrEP in the setting of chronic kidney disease (CKD) with concomitant tacrolimus therapy, a known nephrotoxic agent.

Integrating Pre-Exposure Prophylaxis Delivery in Public Health Family Planning Clinics: Lessons Learned From a Programmatic Implementation Project in Kenya

Sexually active African women are a priority population for HIV prevention due to the disproportionately high frequency of new HIV infections. Family planning (FP) clinics offer an already trusted platform that can be used to reach women for HIV prevention services, including pre-exposure prophylaxis (PrEP). In the recent PrEP Implementation in Young Women and Adolescent (PrIYA program), we piloted PrEP implementation in FP clinics in Kisumu, Kenya, and demonstrated that it was possible to integrate PrEP provision in FP systems with a program-dedicated staff. In this perspective, we describe experiences and strategies employed to introduce PrEP implementation in FP clinics and lessons learned. We identified the following lessons for PrEP introduction in FP clinics in Kenya: (1) possible to integrate and generate high enthusiasm for PrEP delivery in FP clinics but persistence on PrEP is a challenge, (2) involvement of national and regional stakeholders is critical for buy-in, contextualization, and sustainability, (3) delivery models that do not integrate fully with existing staff and systems are less sustainable, (4) creatinine testing at PrEP initiation may not be necessary, (5) fully integrated HIV and FP data systems need to be developed, and (6) incorporating implementation science evaluation is important to understand and document effective implementation strategies. In summary, integration of HIV prevention and FP services provides an opportunity to promote one-stop women-centered care efficiently. However, a broader focus on delivery models that utilize existing staff and novel strategies to help women identify their own risk for HIV are needed to ensure greater success and sustainability.

Kidney injury biomarkers during exposure to tenofovir-based preexposure prophylaxis

We previously reported a higher incidence of non-albumin proteinuria and a small but significant decline in estimated glomerular filtration rate (eGFR) among HIV-negative adults randomized to emtricitabine/tenofovir disoproxil fumarate preexposure prophylaxis (FTC/TDF PrEP) versus placebo. In a nested case--control study among participants randomized to FTC/TDF PrEP, established kidney injury biomarkers measured at 12 months were not significantly different between participants who subsequently experienced one of these kidney endpoints and randomly selected controls who did not.

PrEP for HIV Prevention: Evidence, Global Scale-up, and Emerging Options

Antiretroviral pre-exposure prophylaxis (PrEP) for the prevention of HIV infection was demonstrated to be efficacious and safe earlier this decade from pivotal studies using oral emtricitabine-tenofovir disoproxil fumarate. Regulatory approval and normative guidance, now for almost 70 countries worldwide, has followed. Demonstration projects have shown high uptake and population-level HIV reductions, highlighting the need for simplifying delivery and reducing current barriers to access and persistence. A portfolio of additional, next-generation PrEP formulations, currently under testing, if effective, will offer users choice and likely increase coverage and impact.

HIV preexposure prophylaxis with tenofovir disoproxil fumarate/emtricitabine and changes in kidney function and tubular health

OBJECTIVE

To evaluate the effects of HIV preexposure prophylaxis (PrEP) with tenofovir disoproxial fumurate (TDF)/emtricitabine (FTC) on kidney function and kidney tubular health.

DESIGN

The Iniciativa Profilaxis Pre-Exposicion open-label extension (iPrEx-OLE) study enrolled former PrEP trial participants to receive open-label TDF/FTC. This study included 123 iPrEx-OLE participants who demonstrated PrEP adherence.

METHODS

We compared estimated glomerular filtration rate calculated using serum creatinine (eGFRcr), serum cystatin C (eGFRcys), and in combination (eGFRcr-cys), and a panel of 14 urine biomarkers reflecting kidney tubular health before and 6 months after PrEP initiation.

RESULTS

At baseline, mean eGFRcr, eGFRcys, and eGFRcr-cys were 108.3, 107.0, and 111.1 ml/min per 1.73 m, respectively. Six months after PrEP initiation, eGFRcr declined by -4% (95% CI: -5.7 to -2.4%), eGFRcys declined by -3.3% (95% CI: -8.3 to 1.9%), and eGFRcr-cys declined by -4.1% (95% CI: -7.5 to -0.7%). From the urine biomarker panel, α1-microglobulin and β2-microglobulin increased by 22.7% (95% CI: 11.8--34.7%) and 14.1% (95% CI: -6.1 to 38.6%), whereas chitinase-3-like 1 protein and monocyte chemoattractant protein-1 decreased by -37.7% (95% CI: -53.0 to -17.3%) and -15.6% (95% CI: -31.6 to 4.2%), respectively. Ten of the 14 urine biomarkers, including albumin, had estimated changes of less than 12% with wide confidence intervals.

CONCLUSION

Six months of PrEP with TDF/FTC was associated with decreases in eGFRcr and eGFRcys. We also observed for the first time changes in flour of 14 urine biomarkers reflecting kidney tubular health. These findings demonstrate that PrEP has direct effects on eGFR and the proximal tubule.

Viewpoint: Why you should provide HIV pre-exposure prophylaxis (PrEP) at your college health center

By providing HIV pre-exposure prophylaxis, or PrEP (a single daily oral pill), in a primary care college health setting, clinical providers can make a dramatic contribution to the current and long-term health and well-being of the students they see. This viewpoint article describes the approach taken to instituting primary care PrEP services at two college health programs. It delineates which students might benefit from PrEP and how to prescribe/monitor PrEP over time. Additionally, common barriers to PrEP are reviewed, including concerns about affordability, and the concerns that the use of PrEP will encourage risky sexual activity. Implementation strategies are discussed, including identifying a clinic champion, partnering with knowledgeable colleagues, and developing an educational campaign.

Changes in kidney function among men having sex with men starting on demand tenofovir disoproxil fumarate - emtricitabine for HIV pre-exposure prophylaxis

INTRODUCTION

Daily pre-exposure prophylaxis (PrEP) with tenofovir disoproxil fumarate/emtricitabine (TDF/FTC) is associated with a small but statistically significant decrease in estimated glomerular filtration rate (eGFR). We assessed the renal safety of on-demand PrEP with TDF/FTC in HIV-1 uninfected men.

METHODS

We used data from the randomized double-blind placebo-controlled ANRS-IPERGAY trial and its open-label extension conducted between February 2012 and June 2016 among HIV-uninfected MSM starting on-demand PrEP. Using linear mixed model, we evaluated the mean eGFR decline from baseline over time and determined risks factors associated with eGFR decline during the study.

RESULTS

During the blind phase, with a median follow-up of 9.4 months, the mean decline slope of eGFR from baseline was -0.88 and -1.53 mL/min/1.73 m2 per year in the placebo (n = 201) and the TDF/FTC group (n = 198) respectively, with a slope difference of 0.65 mL/min/1.73 m2 per year (p = 0.27). Including both phases, 389 participants started on-demand TDF/FTC with a median follow-up of 19.2 months and a mean decline of eGFR from baseline of -1.14 mL/min/1.73 m2 per year (p < 0.001). The slope of eGFR reduction was not significantly different in participants with baseline eGFR ≤ 90 mL/min/1.73 m2 (p = 0.44), age >40 years (p = 0.24) or hypertension (p = 0.21). There was a dose-response relationship between recent tenofovir exposure and lower eGFR when considering the number of pills taken in the two months prior the visit (eGFR difference of -0.88 mL/min/1.73 m2 between >15 pills/month vs. ≤15 pills/month, p < 0.01) or plasma tenofovir concentrations at the visit (eGFR difference compared to ≤2 ng/mL: >2 to ≤10ng/mL: -0.98 mL/min/1.73 m2 , >10 to ≤40ng/mL: -1.28 mL/min/1.73 m2 , >40 ng/mL: -1.82 mL/min/1.73 m2 , p < 0.001). Three participants discontinued TDF/FTC for eGFR < 60 mL/min/1.73 m2 during the OLE phase. No case of Fanconi syndrome was reported.

CONCLUSIONS

The renal safety of on-demand PrEP with TDF/FTC was good. The overall reduction and intermittent exposure to TDF/FTC may explain this good renal safety.

Impact of Tenofovir-Based Pre-exposure Prophylaxis on Biomarkers of Bone Formation, Bone Resorption, and Bone Mineral Metabolism in HIV-Negative Adults

BACKGROUND

Pre-exposure prophylaxis (PrEP) with emtricitabine (FTC)/tenofovir disoproxil fumarate (TDF) reduces the risk of HIV seroconversion but may promote bone mineral density (BMD) decline. The mechanisms of BMD decline with FTC/TDF remain unclear, and studies in HIV-positive individuals have been confounded by the effects of HIV and concomitant antiretroviral medications. We evaluated the impact of FTC/TDF on biomarkers of bone remodeling and bone mineral metabolism in HIV-negative men and women enrolled in the Partners PrEP Study.

METHODS

In a random sample of HIV-negative participants randomized to FTC/TDF PrEP (n = 50) or placebo (n = 50), serum parathyroid hormone (PTH), bone biomarkers (C-telopeptide, procollagen 1 intact N-terminal propeptide, and sclerostin), and plasma fibroblast growth factor 23 were measured at baseline and month 24, and the percentage change was compared between groups. In a complementary analysis, we compared the change in biomarkers between participants with and without a 25% decline in glomerular filtration rate (GFR) on FTC/TDF.

RESULTS

Baseline characteristics were similar between the groups (median age, 38 years; 40% women). Vitamin D insufficiency was common, but baseline GFR and PTH were in the normal range. We observed a significantly greater percent increase in serum C-telopeptide in participants randomized to FTC/TDF vs placebo (P = .03), suggesting an increase in bone remodeling. We observed no differences in the other biomarkers, or in a separate analysis comparing participants with and without a decline in GFR.

CONCLUSIONS

Increased bone remodeling may mediate the BMD decline observed with tenofovir-containing PrEP and antiretroviral therapy, independent of a TDF-mediated decrease in kidney function.

HIV-1 self-testing to improve the efficiency of pre-exposure prophylaxis delivery: a randomized trial in Kenya

Background

The introduction of pre-exposure prophylaxis (PrEP) for human immunodeficiency virus-1 (HIV-1) prevention in Africa presents new challenges for health systems that are already overburdened because PrEP delivery requires frequent clinic visits (generally every 3 months) for HIV-1 testing and PrEP refills. HIV-1 self-testing (HIVST) has the potential to improve the efficiency of PrEP delivery by decreasing the number of clinic visits. Here, we describe the rationale and design of a randomized, noninferiority trial designed to test the effectiveness and safety of using HIVST to support PrEP delivery in Kenya.

Methods

The JiPime-JiPrEP (Kiswahili for ‘Test Yourself, PrEP Yourself’) study is a three-arm randomized trial taking place in Thika, Kenya. Participants (n = 495) are eligible for enrollment if they are at least 18 years old, HIV-1 seronegative, and have been taking PrEP for 1 month. Three distinct participant types will be enrolled: men (n = 165) and women (n = 165) who are in mutually disclosed HIV-1 serodiscordant relationships, and women (n = 165) who are at HIV-1 risk and not in a known serodiscordant relationship. Participants in each of these subpopulations will be 1:1:1 randomized to: 1) the standard of care, with quarterly clinic visits; 2) oral HIVST, with biannual clinic visits plus oral HIVSTs to use at the quarters between those visits; or 3) blood-based HIVST, with biannual clinic visits plus blood-based HIVSTs. All participants will complete quantitative surveys and provide blood samples for the objective measurement of PrEP adherence at baseline, 6 months, and 12 months. The primary outcomes are PrEP adherence, PrEP continuation, and HIV-1 testing, measured at 6 months and secondarily at 12 months.

Discussion

The findings from this trial can help to understand how HIVST—a new HIV-1 testing technology—can support health systems in sub-Saharan Africa. Additionally, the findings can inform policy aimed at improving the efficiency of PrEP implementation and scale-up in Kenya.

Trial registration

ClinicalTrials.gov, NCT03593629. Retrospectively registered on 20 July 2018.

Electronic supplementary material

The online version of this article (10.1186/s13063-019-3521-2) contains supplementary material, which is available to authorized users.

Effect of Vitamin D Supplementation on Bone Turnover Markers During HIV Pre-Exposure Prophylaxis Using Tenofovir Disoproxil Fumarate-Emtricitabine in Men Who Have Sex with Men

Pre-exposure prophylaxis (PrEP) with tenofovir disoproxil fumarate-emtricitabine (TDF-FTC) reduces bone mineral density in HIV-uninfected men who have sex with men (MSM). We hypothesized that PrEP with TDF-FTC would increase bone turnover markers (BTMs) at week 24 and that vitamin D supplementation from weeks 24 to 48 would blunt this increase. Participants were from a cohort of 398 MSM and transgender women who received daily TDF-FTC for PrEP. At week 24, a prospective intervention group initiated vitamin D3 4,000 IU daily. Concurrent controls were selected from the cohort who took ≤400 IU/day of vitamin D3 matched by age, race, and body mass index. The primary endpoint was the change in procollagen-I N-terminal propeptide (P1NP) from weeks 24 to 48. Paired t-tests were used to compare changes in BTMs between intervention and controls. Among 48 intervention-control pairs, median age was 33 years. At baseline, 68.9% of the intervention group and 77.3% of controls were vitamin D sufficient (≥20 ng/mL, p = .94). P1NP, C-telopeptide, parathyroid hormone (PTH), and 25-OH vitamin D3 did not increase significantly at week 24. P1NP fell by a mean ± SD of -27.6 ± 49.9 pg/mL from weeks 24 to 48 with vitamin D and -2.5 ± 40.2 pg/mL in controls (p = .01). There were no significant between-group differences in the weeks 24-48 change in C-telopeptide, PTH, or 25-OH vitamin D3. Vitamin D3 supplementation with 4,000 IU/day resulted in a significant reduction in the BTM P1NP compared with controls, suggesting that this intervention has potential to improve bone health during PrEP.

Antiretroviral agents in pre-exposure prophylaxis: emerging and advanced trends in HIV prevention

OBJECTIVES

Antiretroviral agents (ARVs) have been the most promising line of therapy in the management of human immunodeficiency virus (HIV) infections. Some of these ARVs are used in the pre-exposure prophylaxis (PrEP) to suppress the transmission of HIV. Prophylaxis is primarily used in uninfected people, before exposure, to effectively prevent HIV infection. Several studies have shown that ART PrEP prevents HIV acquisition from sexual, blood and mother-to-child transmissions. However, there are also several challenges and limitations to PrEP. This review focuses on the current antiretroviral therapies used in PrEP.

KEY FINDINGS

Among ARVs, the most common drugs employed from the class of entry inhibitors are maraviroc (MVC), which is a CCR5 receptor antagonist. Other entry inhibitors like emtricitabine (FTC) and tenofovir (TFV) are also used. Rilpivirine (RPV) and dapivirine (DPV) are the most common drugs employed from the Non-nucleoside reverse transcriptase inhibitor (NNRTIs) class, whereas, tenofovir disoproxil fumarate (TDF) is primarily used in the Nucleoside Reverse Transcriptase Inhibitor (NRTIs) class. Cabotegravir (CAB) is an analog of dolutegravir, and it is an integrase inhibitor. Some of these drugs are also used in combination with other drugs from the same class.

SUMMARY

Some of the most common pre-exposure prophylactic strategies employed currently are the use of inhibitors, namely entry inhibitors, non-nucleoside reverse transcriptase inhibitors, nucleoside reverse transcriptase inhibitors, integrase and protease inhibitors. In addition, we have also discussed on the adverse effects caused by ART in PrEP, pharmacoeconomics factors and the use of antiretroviral prophylaxis in serodiscordant couples.

Pre-exposure Prophylaxis With Tenofovir Disoproxil Fumarate/Emtricitabine and Kidney Tubular Dysfunction in HIV-Uninfected Individuals

BACKGROUND

Pre-exposure prophylaxis (PrEP) with tenofovir disoproxil fumarate (TDF) and emtricitabine (FTC) is becoming increasingly adopted for HIV prevention. Tenofovir can cause proximal tubular damage and chronic kidney disease in HIV-infected persons, but little is known regarding its nephrotoxic potential among HIV-uninfected persons. In this study, we evaluated the effects of PrEP on urine levels of the following: α1-microglobulin (α1m), a marker of impaired tubular reabsorption; albuminuria, a measure of glomerular injury; and total proteinuria.

SETTING

The Iniciativa Profilaxis Pre-Exposicion (iPrEx) study randomized HIV-seronegative men and transgender women who have sex with men to oral TDF/FTC or placebo. The iPrEx open-label extension (iPrEx-OLE) study enrolled former PrEP trial participants to receive open-label TDF/FTC.

METHODS

A cross-sectional analysis compared urine biomarker levels by study arm in iPrEx (N = 100 treatment arm, N = 100 placebo arm). Then, urine biomarker levels were compared before and after PrEP initiation in 109 participants of iPrEx-OLE.

RESULTS

In iPrEx, there were no significant differences in urine α1m, albuminuria, or proteinuria by treatment arm. In iPrEx-OLE, after 24 weeks on PrEP, urine α1m and proteinuria increased by 21% [95% confidence interval (CI): 10 to 33] and 18% (95% CI: 8 to 28), respectively. The prevalence of detectable α1m increased from 44% to 65% (P < 0.001) and estimated glomerular filtration rate declined by 4 mL/min/1.73 m (P < 0.001). There was no significant change in albuminuria (6%; 95% CI: -7% to 20%).

CONCLUSION

PrEP with TDF/FTC was associated with a statistically significant rise in urine α1m and proteinuria after 6 months, suggesting that PrEP may result in subclinical tubule dysfunction.

Renal function and risk factors for renal disease for patients receiving HIV pre-exposure prophylaxis at an inner metropolitan health service

Background

Pre-exposure prophylaxis (PrEP) with tenofovir disoproxil fumarate/emtricitabine (TDF/FTC) significantly reduces the risk of HIV acquisition. TDF is a known nephrotoxin however, renal dysfunction from TDF is mostly reversible following discontinuation.

Aims

To describe the renal function, risk factors for renal disease and associated clinical testing practices in a cohort of PrEP patients.

Methods

A retrospective review was conducted of all PrEP patients commenced on TDF/FTC at an inner metropolitan sexual health clinic in Sydney, Australia between April 2016 and July 2017, with follow-up data obtained at 3-monthly intervals until 18 months.

Results

525 patients met inclusion criteria. Patients were almost exclusively male and median age was 34 years (IQR: 28 to 42). At baseline, 1.5% had an estimated glomerular filtration rate (eGFR) <70 mL/min/1.73m². A small significant drop in eGFR of -2.5 mL/min/1.73m² (p<0.05) occurred between PrEP commencement and the first follow-up period, followed by a progressive decline in eGFR of -0.38 mL/min/1.73m² per month (95%CI: -0.57 to -0.20; p<0.001). Renal impairment (eGFR <70 mL/min/1.73m²) occurred in 6.5% of patients and persisted across consecutive follow-up periods in five (1.0%) patients. Patients aged ≥40 years had a greater risk of renal impairment than younger patients (HR 3.9, 95%CI: 1.8 to 8.4; p<0.001), despite similar rates of eGFR decline (p = 0.19). PrEP was discontinued in two patients (0.4%) due to renal function concerns.

Conclusion

PrEP use led to an initial drop in eGFR and a more gradual progressive decline subsequently, but significant renal impairment remained uncommon up to 18 months of follow-up.

Scale up of PrEP integrated in public health HIV care clinics: a protocol for a stepped-wedge cluster-randomized rollout in Kenya

Background

Antiretroviral therapy (ART) for HIV-infected persons and pre-exposure prophylaxis (PrEP) for uninfected persons are extraordinarily effective strategies for HIV prevention. In Africa, the region which shoulders the highest HIV burden, HIV care is principally delivered through public health HIV care clinics, offering an existing platform to incorporate PrEP delivery and maximize ART and PrEP synergies. However, successfully bringing this integrated approach to scale requires an implementation science evaluation in public health settings.

Methods

The Partners Scale Up Project is a prospective, pragmatic implementation evaluation, designed as a stepped-wedge, cluster-randomized trial, operating at 24 clinics in Kenya. In collaboration with the Kenya Ministry of Health, we are catalyzing scaled implementation of PrEP delivery integrated in HIV care clinics. The intervention package includes staff training, clinic streamlined access to PrEP commodity from the Kenya Medical Supply Authority, and ongoing intensive technical assistance to rigorously assess how PrEP delivery is implemented. PrEP service delivery including retention efforts are conducted by the clinic staff with no additional resources from the project. Guided by the RE-AIM (Reach, Effectiveness, Adoption, Implementation, Maintenance) framework and Consolidated Framework for Implementation Science Research, project progress and learning are documented through ongoing monitoring and process evaluations, including chart abstraction and individual and key informant interviews, to evaluate pragmatic rollout and understand barriers and facilitators for successful PrEP delivery in this setting. In this staged rollout design, each step provides data for both pre-implementation (baseline) and implementation periods, and we will compare time points across steps in the baseline versus implementation periods.

Discussion

Cost-effective delivery models are urgently needed to maximize the public health impact of PrEP and ART. The Partners Scale Up Project will set the stage for full-scale PrEP implementation fully run and owned by the Kenya Ministry of Health. The work combines nationally sponsored PrEP delivery with technical support and implementation science from academic partners, defining a new but sustainable paradigm for public health collaboration.

Trial registration

Registered with ClinicalTrials.gov on February 14, 2017:NCT03052010.

Potential kidney toxicity from the antiviral drug tenofovir: new indications, new formulations, and a new prodrug

PURPOSE OF REVIEW

The antiviral agent tenofovir is highly effective for the treatment of HIV and hepatitis B virus infections, and the older prodrug tenofovir disoproxil fumarate (TDF) is also a component of daily preexposure prophylaxis (PrEP) to reduce the risk of HIV infection in high-risk populations. Although TDF is well tolerated, the potential for kidney and bone toxicity has important implications for public health given the large number of individuals exposed to TDF worldwide. This review summarizes the recent literature on kidney and bone health in individuals treated with TDF and the newer prodrug tenofovir alafenamide (TAF).

RECENT FINDINGS

Risk factors for TDF toxicity appear to be similar in patients treated for HIV or hepatitis B virus and in HIV-uninfected PrEP users, although drug-drug interactions are a more important concern in HIV-positive individuals. The risk of toxicity appears to be lower with TAF, but further studies are needed to confirm the safety of long-term use and to evaluate the efficacy of TAF-based PrEP.

SUMMARY

Nephrologists should be aware of the potential kidney and bone toxicity of TDF, as well as unique situations in which the newer prodrug TAF may contribute to kidney injury.

HIV preexposure prophylaxis: An essential, safe and effective prevention tool for sexual health

Preexposure prophylaxis of HIV with antiretroviral drugs is a prevention tool available in France since 2016, combined with the prevention methods already used (condoms, post-exposure treatment, rapid treatment of diagnosed HIV infections, etc.). It is targeted at populations at high risk of HIV infection, especially men who have sex with men, for whom traditional prevention methods are insufficient. We collected clinical research data, which resulted in the launch of preexposure prophylaxis in the United States and then elsewhere in the world, safety, tolerability and cost data, as well as ongoing research data (new molecules/methods of administration). We also provided an update of its use in France.

Brief Report: Frequency of Monitoring Kidney Function in HIV-Uninfected Persons Using Daily Oral Tenofovir Disoproxil Fumarate Pre-exposure Prophylaxis

BACKGROUND

Wide-scale implementation of oral tenofovir-based pre-exposure prophylaxis (PrEP) for HIV prevention is now policy in many settings. However, the optimal frequency for monitoring kidney function remains uncertain. We investigated the impact of 6-monthly compared with 3-monthly creatinine clearance (CrCl) monitoring on the identification of moderate kidney dysfunction, defined as CrCl <60 mL/min.

METHODS

Data were from 2 prospective daily oral PrEP studies in Kenya and Uganda: the Partners PrEP Study, a randomized safety, and efficacy trial of PrEP that conducted 3-monthly CrCl monitoring (n = 4404) and the Partners Demonstration Project (n = 954), an open-label delivery study of PrEP that used 6-monthly monitoring. CrCl ≥60 mL/min was required for enrollment in both studies. Abnormal results were followed with confirmatory testing within approximately 1 week. Follow-up was for up to 24 months.

RESULTS

Of 5358 participants included in the analysis, 87% were younger than 45 years, a third were female, and 21% had a baseline CrCl between 60 and 90 mL/min. Confirmed CrCl <60 mL/min events were rare, occurring in 52 individuals (<1%) in 24 months. The 12-month cumulative proportion of persons with CrCl <60 mL/min was 0.2% with 3-monthly screening and 0.5% with 6-monthly screening. Older age (>45 years), lower weight (<55 kg), elevated blood pressure (>140 mm Hg), and baseline CrCl between 60 and 90 mL/min were independently associated with CrCl decline <60 mL/min during follow-up.

CONCLUSIONS

In these 2 PrEP studies, with generally young participants, the occurrence and pattern of clinically relevant decline in CrCl were not qualitatively different based on 3- or 6-monthly CrCl monitoring schedule. These data suggest that for most persons receiving PrEP for up to 24 months, less frequent CrCl monitoring would be safe and reduce required expenditures for repeat confirmatory testing.

Cumulative exposure of TDF is associated with kidney tubulopathy whether it is currently used or discontinued

OBJECTIVE

Tenofovir disoproxil fumarate (TDF) increases the risk of kidney tubular dysfunction (KTD). This study was conducted to elucidate whether KTD persists after discontinuation of TDF.

DESIGN

A prospective cross-sectional study which enrolled 941 HIV-1-infected patients.

METHODS

KTD was predefined as the presence of at least two abnormalities among the five tubular markers (fractional excretion of phosphate, fractional excretion of uric acid, β2 microglobulinuria, N-acetyl-β-D-glucosaminidase, nondiabetic glycosuria). Logistic regression model was used to examine the association between KTD and cumulative TDF use, as well as current status of TDF use.

RESULTS

In total, 94% of study patients were men (median age 45, estimated glomerular filtration rate 75 ml/min per 1.73 m, CD4 575 cells/μl. About 98% were on antiretroviral therapy. In total, 64% of the patients ever used TDF and 39% currently used TDF. Twenty-nine percent used TDF for more than 5 years. KTD was diagnosed in 116 (12%) patients. In multivariate model, more than 5 years of TDF exposure and current TDF use [odds ratio (OR) 4.2, 95% confidence interval (CI) 2.37-7.56], more than 5 years and past TDF use (OR 2.4, 95% CI 1.09-5.33), less than 5 years and current TDF (OR 2.4, 95% CI 1.24-4.85), and less than 5 years and past TDF (OR 2.4, 95% CI 1.22-4.64) were all significantly associated with KTD, with never TDF use as reference. The results were the same using 4 and 3 years of exposure as the cutoff. However, with 2 years exposure, both less than 2 years and current TDF (OR 2.3, 95% CI 0.84-6.20) and less than 2 years and past TDF (OR 1.9, 95% CI 0.73-4.93) were not associated with KTD, whereas both more than 2 years and current TDF and more than 2 years and past TDF were associated.

CONCLUSION

The association between cumulative TDF use and KTD was strong and robust. The results of the study suggested that TDF-related KTD might persist after discontinuation of TDF if patients used TDF for more than 2 years.

Concomitant AIDS cholangiopathy and Fanconi syndrome as complications of HIV in a single patient

We describe the case of a 50-year-old woman presenting to our acute medicine department with generalised non-specific symptoms on a background of HIV managed on triple therapy (tenofovir, lamivudine and zidovudine). On admission, she was noted to be acidotic with proteinuria, glycosuria, hypophosphataemia and generalised body pain, and was diagnosed with Fanconi's renotubular syndrome secondary to tenofovir. It was also noted that she had elevated liver dysfunction markers, and an MRI of the liver revealed a focal stricture near the ampulla of Vater, resulting in a diagnosis of AIDS cholangiopathy. These two diagnoses are rare complications of HIV, and the presence of both these pathologies in a single patient has never been reported in the literature before, and we therefore believe that this case is the first of its kind.

Kidney Disease in HIV: Moving beyond HIV-Associated Nephropathy

In developed countries, remarkable advances in antiretroviral therapy have transformed HIV infection into a chronic condition. As a result, HIV-associated nephropathy, the classic HIV-driven kidney lesion among individuals of African descent, has largely disappeared in these regions. However, HIV-positive blacks continue to have much higher rates of ESRD than HIV-positive whites, which could be attributed to the APOL1 renal risk variants. Additionally, HIV-positive individuals face adverse consequences beyond HIV itself, including traditional risk factors for CKD and nephrotoxic effects of antiretroviral therapy. Concerns for nephrotoxicity also extend to HIV-negative individuals using tenofovir disoproxil fumarate-based pre-exposure prophylaxis for the prevention of HIV infection. Therefore, CKD remains an important comorbid condition in the HIV-positive population and an emerging concern among HIV-negative persons receiving pre-exposure prophylaxis. With the improved longevity of HIV-positive individuals, a kidney transplant has become a viable option for many who have progressed to ESRD. Herein, we review the growing knowledge regarding the APOL1 renal risk variants in the context of HIV infection, antiretroviral therapy-related nephrotoxicity, and developments in kidney transplantation among HIV-positive individuals.

Drug safety evaluation of oral tenofovir disoproxil fumarate-emtricitabine for pre-exposure prophylaxis for human immunodeficiency virus infection

INTRODUCTION

Tenofovir disoproxil fumarate (TDF) and emtricitabine (FTC) are nucleoside reverse transcriptase inhibitors approved as pre-exposure prophylaxis (PrEP) against human immunodeficiency virus (HIV). Prophylactic TDF-based regimens have been shown to reduce the risk of HIV infection by 74 to 92% among participants with detectable drug levels. Adverse events observed in clinical trials include nausea, elevated creatinine and liver enzymes, and decreased bone mineral density.

AREAS COVERED

This article reviews the pharmacology, pharmacokinetics, and the safety profile of TDF and FTC used as PrEP for HIV infection.

EXPERT OPINION

TDF-FTC can have a large impact in preventing HIV infections among high risk individuals when taken daily. Although TDF-FTC is associated with adverse events, they can be minimized with clinician-guided monitoring.

HIV pre-exposure prophylaxis for women

Women and girls comprise nearly half of HIV-infected individuals globally and 20% of new infections in the United States, indicating an urgent need to optimise HIV prevention options in this population. HIV pre-exposure prophylaxis (PrEP) - where antiretrovirals are administered to HIV-non-infected individuals at risk of HIV acquisition - is a promising, female-controlled HIV prevention strategy but has so far been underutilised in women. Clinical trial data demonstrate efficacy of daily oral tenofovir disoproxil fumarate/emtricitabine (TDF/FTC) for reduction of HIV acquisition among women when used consistently. Limited HIV risk perception and suboptimal PrEP awareness among women and healthcare personnel are among the challenges with PrEP delivery for women. Future research into the development of new drugs and delivery systems, and integrating PrEP delivery with reproductive healthcare services, provide opportunities to optimise this prevention strategy for women.