Greater change in bone turnover markers for efavirenz/emtricitabine/tenofovir disoproxil fumarate versus dolutegravir + abacavir/lamivudine in antiretroviral therapy-naive adults over 144 weeks

Correlation of serum anti-Mullerian hormone and Inhibin-B levels with osteoporosis of menopausal woman in Chinese Daur ethnic group

PURPOSE

To investigate the diagnostic value of anti-Mullerian hormone (AMH) and Inhibin B (InhB) in menopausal women with osteoporosis from the Chinese Daur ethnic group.

METHODS

A total of 175 menopausal women were selected and divided into the osteoporosis group (N = 90) and the control group (N = 85). BMD was measured by dual-energy X-ray absorptiometry, and laboratory indicators of osteoporosis, for example, serum osteocalcin (OC), β-collagen special sequence (β-CTX), and procollagen type I amino-terminal propeptide (PINP), bone alkaline phosphatase (BALP), AMH, and InhB were measured by commercial kits. The relationship between osteoporosis and AMH or InhB was analyzed. The predictive values of AMH and InhB were reflected by the ROC curve and logistic regression.

RESULTS

The level of BMD was decreased and the levels of OC, β-CTX, PINP, and BALP of the menopausal osteoporosis group were increased. The concentration of AMH and InhB in the menopausal osteoporosis group was decreased and they had connections with each other. AMH and InhB could be used as independent indicators for the occurrence of osteoporosis in menopausal women and their combination had a higher diagnostic value.

CONCLUSION

AMH and InhB measurements in menopausal women had a certain clinical significance in the detection of osteoporosis. The occurrence of osteoporosis was related to BMD, OC, β-CTX, BALP, AMH, and InhB.

Efficacy and Safety of Pre-Exposure Prophylaxis to Control HIV and Sexually Transmitted Infection Among Men Who Have Sex With Men: Protocol for a Single-Arm Interventional Study

BACKGROUND

Pre-exposure prophylaxis (PrEP) against HIV infection is a new approach that involves the prophylactic use of the anti-HIV drug Truvada (tenofovir disoproxil fumarate [TDF] and emtricitabine [FTC]) by people not infected with HIV.

OBJECTIVE

The objective of this investigator-initiated clinical study of PrEP was to evaluate the incidence of HIV and sexually transmitted infection (STI), safety and efficacy of PrEP in PrEP users, and their compliance with PrEP medication. The social, medical, and economic benefits of PrEP in Japan was assessed.

METHODS

This single-center feasibility study of PrEP was conducted at the National Center for Global Health and Medicine, Tokyo, Japan, where a cohort of men who have sex with men without HIV was established in January 2017. This single-arm interventional study compared the efficacy and safety of PrEP in a single group of men who have sex with men who participated in PrEP cohort studies. For reference, the cohort study participants who did not participate in the PrEP study were included for comparison. Blood samples were collected for storage at baseline and clinic visits at 1, 3, and 6 months after starting PrEP and every 3 months thereafter. The participants were administered with 1 tablet of Truvada once daily as PrEP. They underwent blood and anal swab tests 1 and 3 months after starting PrEP and then HIV and STI infection assessments at 3-month intervals. Blood samples were centrifuged at the AIDS Clinical Center Laboratory. PrEP safety was evaluated by monitoring serum creatinine levels for symptoms of renal function disorders. The primary end point was the incidence of HIV in PrEP users (100 person-years). The secondary end points were the incidence of STI in PrEP users (100 person-years), incidence of adverse events caused by Truvada, frequency of high-risk sexual activity, and adherence to periodic visits and medication.

RESULTS

The study protocol was reviewed and approved by the certified review board of the National Center for Global Health and Medicine (NCGM-C-003129-03) on April 20, 2020. Changes to the study plan were submitted for review by the certified review board and approved before implementation. Recruitment was completed on March 28, 2019, and the study was completed (last adult participant and last time point) on March 31, 2021. The data were analyzed, and the main results of the study have been published in a peer-reviewed journal.

CONCLUSIONS

The findings indicated that PrEP is a highly effective and feasible strategy against HIV infection in terms of prophylactic response, retention, and compliance.

TRIAL REGISTRATION

UMIN Clinical Trials Registry UMIN000031040; https://tinyurl.com/3msdkeb8 and Japan Registry of Clinical Trials jRCTs031180134; https://tinyurl.com/2p88mhyr.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

RR1-10.2196/50919.

Changes in bone quality after switching from a TDF to a TAF based ART: A pilot randomized study

BACKGROUND

The impact of tenofovir disoproxil fumarate (TDF) antiretroviral (ART) regimens on bone health has been characterized mostly by bone mineral density (BMD), but recently also by bone quality (BQ). The aim of this pilot study is to assess the changes in BMD and BQ after switch from TDF to tenofovir alafenamide (TAF) ART.

METHODS

HIV individuals receiving TDF-based ART were randomized to switch to Bictegravir-TAF-Emtricitabine or to remain in the same regimen. At baseline and 24-weeks after randomization, participants underwent bone mineral density (BMD) by DXA and BQ assessment using bone microindentation, a validated technique that measures bone tissue quality expressed as bone material strength index (BMSi). A panel of plasma bone turnover biomarkers were measured by ELISA at the same time-points. Values are expressed as median [interquartile range] and non-parametric tests were used where appropriate.

RESULTS

A total of 24 HIV individuals were included in the study, 19 of which were men (80%). Median age at baseline was 43 years (IQR 38-54). Half of individuals were allocated in the TDF group while the other half changed to TAF treatment. No differences at baseline between both groups were detected in any parameter. Non-significant changes nor in lumbar or femoral BMD at week 24 was found in any regimen. In contrast, there was an increase in BMSi in the TAF arm at 24 weeks, and thus an improvement in BQ[81.6 (79-83) to 86 (80-88) (+5.1%);p=0.041], whereas the TDF arm remained stable from 82 (76-85) at baseline to 82 (73-83);p=0.812. Hence, at week 24 there were significant differences in BQ between arms (p=0.049). A reduction in bone formation markers was found at week 24 in both regimens: N-terminal propeptide of type-1 collagen decreased a 20% (-35 - -0.6); p=0.031 with TAF and -16% (-25 - -5); p=0.032 with TDF. Also a decrease in bone resorption marker C-telopeptide with TAF was detected [-10% (-19 - -5);p=0.028] but not with TDF (p=0.232), suggesting a less metabolically active bone after switching to TAF.

CONCLUSION

A bone quality improvement was found after switching from a TDF to a TAF based ART independently of BMD, suggesting that the bone health benefits of TAF may extend beyond BMD. Future research should be directed to confirm these findings and to identify the underlying mechanisms of ART related bone toxicity.

The renal-bone axis in older people living with HIV on stable antiretroviral therapy: A sub-analysis of the GS-US-104-0423 study

BACKGROUND

Data on low bone mineral density (BMD) in people living with HIV (PLWH) are mainly derived from younger adults; little is known about how antiretroviral therapy (ART) and alterations in the renal-bone axis relate to BMD in older PLWH.

METHODS

Cross-sectional study of men > 50 years and post-menopausal women with HIV. Antiretroviral therapy exposure was stratified into four groups based on use of tenofovir disoproxil fumarate (TDF) and protease inhibitors (PI): non-TDF/non-PI, non-TDF/PI, TDF/non-PI, and TDF/PI. Bone mineral density was measured by dual X-ray absorptiometry (DXA). Bone turnover/regulatory markers and renal tubular function were analysed in stored plasma and urine samples. The association of ART exposure and bone/renal biomarkers on BMD was explored using logistic regression models.

RESULTS

247 individuals (median [IQR] age 57 [53, 65] years; 47% female; 13% of Black ethnicity; CD4 count 643 [473, 811] cells/mm³; and 98% with HIV RNA < 200 copies/mL) were included. Bone turnover and renal tubular function differed significantly by ART exposure. In analyses adjusted for demographic and traditional renal/bone risk factors, exposure to TDF and PI was associated with a fourfold greater risk of low BMD at the femoral neck and exposure to TDF and/or PI with a threefold greater risk of low BMD at the lumbar spine. The relationship between ART and low BMD was not altered by further adjustment for bone turnover or renal tubular function markers.

CONCLUSIONS

The associations between low BMD and ART exposure (TDF vs. non-TDF and boosted vs. unboosted third agents) were minimally affected by adjustments for bone and kidney biomarkers.

Bone Quality in Relation to HIV and Antiretroviral Drugs

PURPOSE OF REVIEW

People living with HIV (PLWH) are at an increased risk for osteoporosis, a disease defined by the loss of bone mineral density (BMD) and deterioration of bone quality, both of which independently contribute to an increased risk of skeletal fractures. While there is an emerging body of literature focusing on the factors that contribute to BMD loss in PLWH, the contribution of these factors to bone quality changes are less understood. The current review summarizes and critically reviews the data describing the effects of HIV, HIV disease-related factors, and antiretroviral drugs (ARVs) on bone quality.

RECENT FINDINGS

The increased availability of high-resolution peripheral quantitative computed tomography has confirmed that both HIV infection and ARVs negatively affect bone architecture. There is considerably less data on their effects on bone remodeling or the composition of bone matrix. Whether changes in bone quality independently predict fracture risk, as seen in HIV-uninfected populations, is largely unknown. The available data suggests that bone quality deterioration occurs in PLWH. Future studies are needed to define which factors, viral or ARVs, contribute to loss of bone quality and which bone quality factors are most associated with increased fracture risk.

Bone and fat hormonal crosstalk with antiretroviral initiation

BACKGROUND

Bone mineral density (BMD) loss and fat gain is common in people living with HIV (PLWH), particularly after initiating combination antiretroviral therapy (cART). Given the close metabolic interaction between bone and fat, we tested the hypotheses that changes in bone-derived hormones are associated with fat accumulation and changes in fat-derived hormones are associated with BMD loss following cART initiation.

METHODS

HIV-seropositive subjects (n = 15) initiating fixed dose cART of tenofovir disoproxil fumarate/emtricitabine/efavirenz (TDF/FTC/EFV) underwent dual X-ray absorptiometry (DXA) assessment pre-cART and again 12-months post-cART initiation. DXA-derived measurements included BMD at the lumbar spine, femoral neck, total hip, and trochanter and the trunk and total fat. Serum undercarboxylated osteocalcin (ucOCN), sclerostin, lipocalin-2, leptin, and adiponectin were measured pre and post-cART. Spearman's rank-order correlations assessed the cross-sectional associations between hormones and bone and fat mass pre- and post-cART. Linear regression models adjusting for baseline bone or fat mass assessed the association between hormone change and BMD/fat changes following cART initiation.

RESULTS

ucOCN (p = 0.04) and lipocalin-2 (p = 0.03) increased post-cART while sclerostin, leptin, and adiponectin remained unchanged. BMD significantly decreased post-cART at all skeletal sites. Trunk and total fat increased post-cART but not significantly, while weight and BMI remained unchanged. In models adjusting for baseline BMD and fat mass, change in ucOCN was negatively associated with change in trunk (p = 0.008) and total fat (p = 0.01) and the change in leptin was positively associated with change in total hip (p = 0.03) and trochanteric BMD (p = 0.02).

CONCLUSION

The current study demonstrates bone-fat crosstalk in cART initiating PLWH.

Combined cART including Tenofovir Disoproxil, Emtricitabine, and Dolutegravir has potent therapeutic effects in HIV-1 infected humanized mice

HIV-1 reservoirs persist in the presence of combined antiretroviral therapy (cART). However, cART has transformed HIV-1 infection into a chronic disease marked by control of HIV-1 viral load and mortality reduction. Major challenges remain, including viral resistance upon termination of cART and persistence and identification of tissue distribution of HIV-1 reservoirs. Thus, appropriate animal models that best mimic HIV-1 pathogenesis are important, and the current study complements our previously published validation of the CD34+ hematopoietic humanized mouse model for this purpose. Here we analyze viral suppression using the recently developed combination of antiretrovirals that include Tenofovir Disoproxil (TDF), Emtricitabine (FTC), and Dolutegravir (DTG), a choice based on recent clinical outcomes showing its improved antiretroviral potency, CD4+ T cell preservation, tolerability, and prevention of viral drug resistance compared to that of previous regimens. We used quantitative Airyscan-based super resolution confocal microscopy of selected mouse tissues. Our data allowed us to identify specific solid tissue reservoirs of human T cells expressing the HIV-1 core protein p24. In particular, lymph node, brain, spleen, and liver were visualized as reservoirs for residual infected cells. Marked reduction of viral replication was evident. Considering that detection and visualization of cryptic sites of HIV-1 infection in tissues are clearly crucial steps towards HIV-1 eradication, appropriate animal models with pseudo-human immune systems are needed. In fact, current studies with humans and non-human primates have limited sample availability at multiple stages of infection and cannot easily analyze the effects of differently administered combined antiretroviral treatments on multiple tissues. That is easier to manage when working with humanized mouse models, although we realize the limitations due to low human cell recovery and thus the number of cells available for thorough and comprehensive analyses. Nonetheless, our data further confirm that the CD34+ humanized mouse model is a potentially useful pre-clinical model to study and improve current anti-HIV-1 therapies.

Bone outcomes in virally suppressed youth with HIV switching to tenofovir disoproxil fumarate

Background

Tenofovir disoproxil fumarate (TDF) is included in first-line antiretroviral treatment (ART) for adolescents living with HIV (ALWH). Associated toxicities remain a concern.

Objective

We evaluated bone and renal safety outcomes in virologically suppressed South African ALWH after switching to TDF.

Method

We recruited virally suppressed (< 100 copies/mL) adolescents, aged 15-20 years, who switched from an abacavir (ABC)-based to a TDF-based efavirenz regimen. Bone mass and renal function were assessed at Week 0 and at Week 24 after the switch to TDF using dual-energy X-ray absorptiometry (DXA) and serum renal markers. A change in the lumbar spine (LS) and the whole-body less head (WBLH) bone mineral density (BMD) Z-scores and the estimated glomerular filtration rate (eGFR) between the two measures were compared (paired t-tests) and stratified by sex.

Results

Fifty participants (48% male), with a median duration of prior ART of 11.4 years, were enrolled. Among 47 participants with 24-week DXA results, 15 (32%) had either no change or a decreased LS-BMD after the switch, with a mean change of -1.6%. Overall, more female participants experienced this outcome: 58% versus 4%, P < 0.0001. The mean change (standard deviation) in the LS-Z-score was -0.03 (0.25) and in the WBLH-Z-score was 0.02 (0.24). A decrease in the eGFR from 132.2 to 120.4 was observed (P = 0.0003); however, the levels remained clinically acceptable.

Conclusion

South African ALWH switching from abacavir to TDF-based ART experienced statistically significant decreases in eGFR but not in LS and WBLH BMD. Female ALWH were more likely to experience a decrease in LS-BMD and may require closer monitoring.

Unveiling the basis of antiretroviral therapy-induced osteopenia: the effects of Dolutegravir, Darunavir and Atazanavir on osteogenesis

OBJECTIVES

Osteopenia is frequent in HIV-infected patients treated with antiretroviral therapy (ART) and has been linked to increased osteoclastogenesis. Little is known about the effects of ART on osteogenesis.

DESIGN

We investigated the effect on human mesenchymal stem cells (hMSC) and osteoblasts of Darunavir and Dolutegravir, the most highly used as anchor drugs within a three-drug regimen, and Atazanavir, which was widely utilized in the past.

RESULTS

We found that Atazanavir and Dolutegravir delay the osteogenic differentiation of hMSC, impair the activity of osteoblasts and inhibit their conversion into osteocytes, whereas Darunavir exerts no effect.

CONCLUSION

Atazanavir and Dolutegravir impair osteogenesis. It is essential to diagnose impaired osteogenesis early and to devise effective therapeutic interventions to preserve bone health in ART-treated HIV patients, putting it in the context of a correct antiretroviral combination.

Association between Nonalcoholic Fatty Liver Disease and Bone Mineral Density in HIV-Infected Patients Receiving Long-term TDF-Based Antiretroviral Therapy

BACKGROUND

Tenofovir (TDF) has a detrimental effect on bone mineral density (BMD), while nonalcoholic fatty liver disease (NAFLD) is associated with a lower BMD.

OBJECTIVE

To help understand the mutual effects of NAFLD and TDF on BMD, this study was designed to explore the potential association between NAFLD and BMD in HIV-infected patients receiving long-term TDF-based antiretroviral therapy (ART).

METHODS

A total of 89 HIV-infected patients who received TDF-based ART for more than three years were enrolled in this cross-sectional study. We measured BMD using an ultrasonic bone density apparatus, and liver ultrasonography was performed to determine the severity of the fatty liver. The association of NAFLD with BMD was examined using multiple logistic regression analyses.

RESULTS

Patients with NAFLD showed a worse BMD status than those without NAFLD. The incidence rates of osteopenia (42.86% versus 25.93%) and osteoporosis (17.14% versus 3.70%) were significantly higher in HIV-infected patients with NAFLD than in those without NAFLD. After multivariate adjustment, the odds ratio (OR) for patients with NAFLD exhibiting a worse BMD status compared with those without NAFLD was 4.49 (95% confidence interval [CI] 1.42, 14.15).

CONCLUSION

Based on our results, NAFLD was significantly associated with a worse BMD status, including osteopenia and osteoporosis, in HIV patients after receiving long-term TDF-based ART. Furthermore, we may want to avoid using TDF for ART in HIV-infected patients with NAFLD.

People living with HIV and fracture risk

PLHIV have an increased risk of osteoporosis and fractures when compared with people of the same age and sex. In this review, we address the epidemiology and the pathophysiology of bone disease and fractures in PLHIV. The assessment of fracture risk and fracture prevention in these subjects is also discussed. The spectrum of HIV-associated disease has changed dramatically since the introduction of potent antiretroviral drugs. Today, the survival of people living with HIV (PLHIV) is close to that of the general population. However, the longer life-span in PLHIV is accompanied by an increased prevalence of chronic diseases. Detrimental effects on bone health are well recognised, with an increased risk of osteoporosis and fractures, including vertebral fractures, compared to the general population. The causes of bone disease in PLHIV are not fully understood, but include HIV-specific risk factors such as use of antiretrovirals and the presence of chronic inflammation, as well as traditional risk factors for fracture. Current guidelines recommend the use of FRAX to assess fracture probability in PLHIV age ≥ 40 years and measurement of bone mineral density in those at increased fracture risk. Vitamin D deficiency, if present, should be treated. Bisphosphonates have been shown to increase bone density in PLHIV although fracture outcomes are not available.

Bone Safety of Dolutegravir-Containing Regimens in People Living with HIV: Results from a Real-World Cohort

Objective

Few data exist about the effect of dolutegravir (DTG) on bone mineral density (BMD) in real life. The aim of this study was to determine rates of change in BMD over time in people living with HIV (PLWH) treated with DTG.

Design

The SCOLTA project is a multicenter observational study enrolling HIV-infected people who start newly commercialized drugs prospectively, with the aim of identifying toxicities and adverse events (AE) in a real-life setting.

Methods

Dual-energy X-ray absorptiometry at the femoral neck (FN) and lumbar spine (LS) was performed at study entry (baseline, BL) and after 96 weeks. Percentage BMD change from BL was evaluated using a general linear model, including factors potentially associated with bone loss.

Results

One hundred and sixty PLWH were enrolled (26.3% female, mean age 49.9 ± 11.2 years) from April 2015 to April 2017. Overall, we could calculate BMD change from baseline, for at least one site, in 133 subjects (83.1%). After a median of 102 weeks (IQR: 90–110), mean FN BMD increased, but not significantly, whereas LS BMD showed a significant mean increase of 13.1 (95% confidence interval, CI: 1.7–24.6) mg/cm³ (+1.6%, 95% CI: 0.3%, 2.8%) after a median time of 102 weeks (IQR: 84–110). As regards LS BMD, patients with osteopenia/osteoporosis at study entry experienced a high increase from baseline (20.6, 95% CI: 3.1, 38.1 mg/cm³), as well as experienced subjects (16.9, 95% CI: 4.7, 29.2 mg/cm³) and those on vitamin D supplementation (26.8, 95% CI: 7.7, 45.9 mg/cm³).

Conclusion

Dolutegravir-containing regimens could reduce the negative impact of antiretroviral therapy on bone, especially in patients with low BMD.

Update on Adverse Effects of HIV Integrase Inhibitors

PURPOSE OF REVIEW

The goal of this paper is to provide an up-to-date review of adverse events related to the class of integrase strand transfer inhibitors (INSTIs), which became the class of choice in few years. We sought answers specifically to issues pertaining to neuropsychiatric adverse events, as well as weight gain, which were the two most important categories of adverse events raised in recent studies based on real-life experience. The primary focus of this paper is on adults with a brief summary on pregnant women and children/adolescents.

RECENT FINDINGS

Dolutegravir (DTG) bears the heaviest burden of neuropsychiatric side effects. Weight gain was reported with all INSTIs, although there are methodological caveats in the analyses and the findings need to be interpreted with caution.Moreover, due to recent findings on neural tube defects in infants exposed to dolutegravir during their peri-conception period, its use is not recommended for women of childbearing age without proper birth control method, while raltegravir remains the only drug which may be prescribed without caution. Given the importance of cognitive and metabolic co-morbidities in people living with HIV in regard to their quality of life, future research needs to focus on long-term effects of INSTIs in relation to these adverse events. Pharmacogenetics seems to be a promising tool. Safety during pregnancy is also another important issue to further clarify.

SUMMARY

INSTIs are a generally well-tolerated class of antiretrovirals (ARV), and has a higher antiviral potency compared to other classes of ARV.Clinicians and patients need however to be aware of some red flags when starting with and monitoring patients on INSTIs.All INSTIs can lead to mild increases in creatinine levels, usually without clinical significance, but caution is needed in patients with low eGFR (<30ml/min), when using other nephrotoxic drugs, such as as tenofovir disoproxil.Neuro-psychiatric (NP) effects are to be monitored with INSTIs, especially with DTG (though reports are at times contradictory); clinicians might want to avoid DTG for patients with history of severe NP symptoms, until clarity is provided.Weight gain was reported with all INSTIs, especially with DTG, with possible differential effects according to sex and ethnicity (female and non-white patients being at increased risk). This is worrying since patients from African descent are at higher risk of cardio-vascular events and increased body mass index (BMI) can cause further increase metabolic risk. There is possibly an additional effect of tenofovir alafenamide (TAF) on weight increase.Discrepancies between clinical trials - with low rates of adverse events - and reports from real-life settings might be due partly to under-representation of some groups of patients in clinical trials, and/or the short duration of follow-up, since some adverse effects may only occur after prolonged exposure.Preliminary data on safety of bictegravir (BIC), from clinical trials and non-trial settings, are very reassuring and seem to show lower rates of adverse events compared to DTG.Elvitegravir/cobicistat (EVG/cobi) need to be used with caution in patients with other co-morbidities given potential for polypharmacy, as it is the case for aging patients, because of the high potential of drug-drug interactions due to effects of the cobicistat booster.We are awaiting the release of cabotegravir (CAB), which could represent a good option for patients struggling with adherence, despite injection site reactions.Pharmacogenetics is a promising way to explore adverse effects occurrence in the INSTI class.

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 Integrase Inhibitor Pharmacogenetics: An Exploratory Study

BACKGROUND AND OBJECTIVES

Integrase strand transfer inhibitors (INSTIs), dolutegravir, elvitegravir, and raltegravir, have become integral in the treatment of HIV, with close monitoring of continued efficacy and tolerability. As side effect occurrence varies among subjects receiving these drugs, we sought to perform an exploratory analysis examining the role of several single-nucleotide polymorphisms (SNPs) on drug concentration changes, selected clinical outcomes, and the occurrence of subject-reported adverse events.

METHODS

Adults (aged ≥ 18 years) receiving INSTI-based regimens for treatment of HIV were recruited and genotyped with an iPLEX ADME PGx Pro v1.0 Panel. Multiple linear or logistic regression with covariates [age, sex, BMI, regimen (in the across-regimen group), regimen duration, and baseline variables (for continuous parameters)] was used to detect significant (p < 0.05) association of selected clinical data with genetic variants within the study population.

RESULTS

In a sample (n = 88) with a median age of 52.5 years (IQR 45.7-57.2) being predominately Caucasian (88.6%) and male (86.4%), this exploratory study discovered several associations between variables and SNPs, when using INSTIs. Abnormal dream occurrence was statistically different (p = 0.028) between regimens. Additionally, several SNPs were found to be associated with adverse event profiles primarily when all regimens were grouped together.

CONCLUSION

The associations found in this study point to a need for further assessment, within the population living with HIV, of factors contributing to unfavorable subject outcomes. These exploratory findings require confirmation in larger studies, which then may investigate pharmacogenetic mechanisms.

Bone Mineral Density Declines Twice as Quickly Among HIV-Infected Women Compared With Men

BACKGROUND

Initial declines in bone mineral density (BMD) after antiretroviral therapy initiation in HIV are well described, but data on long-term changes and risk factors for decline, particularly among women, are limited.

METHODS

HIV-infected men and women in the Modena Metabolic Clinic underwent dual-energy X-ray absorptiometry (DXA) scans every 6-12 months for up to 10 years (median 4.6 years). Mixed effect regression models in combined and sex-stratified models determined annual rates of decline and clinical factors associated with BMD. Models included demographics, HIV-specific factors, and bone-specific factors; a final model added a sex × time interaction term.

RESULTS

A total of 839 women and 1759 men contributed ≥2 DXA scans. The majority (82%) were 50 years and younger; 76% had HIV-1 RNA <50 copies per milliliter at baseline; 15% of women were postmenopausal and 7% of men had hypogonadism; and 30% and 27%, respectively, had hepatitis C virus (HCV) coinfection. The adjusted slopes in BMD among women and men were significantly different at both the femoral neck (women -0.00897 versus men -0.00422 g/cm per year; P < 0.001) and L-spine (women -0.0127 versus men -0.00763 g/cm per year; P < 0.001). Modifiable risks associated with BMD decline included antiretroviral therapy exposure (greater decline with tenofovir disoproxil fumarate and less decline with integrase strand transfer inhibitor therapy), HCV, physical activity, and vitamin D insufficiency.

CONCLUSIONS

Among HIV-infected individuals, bone density at the femoral neck, a significant predictor of fracture risk, declined twice as quickly among women compared with men. Female sex was independently associated with both lower femoral neck and lumbar BMD over time in adjusted models.

The Hidden Burden of Fractures in People Living With HIV

The survival of people living with human immunodeficiency virus (HIV) has increased markedly since the advent of antiretroviral therapy (ART). However, other morbidities have emerged, including osteoporosis. The estimated incidence of fractures at any site in people living with HIV ranges from 0.1 per 1000 person‐years to 8.4 per 1000 person‐years: at least twice that of people without HIV. This increased risk seems to be related to HIV itself and its treatment. Risk factors for bone disease in HIV‐positive (HIV⁺) subjects include both classical risk factors for osteoporosis and fracture and factors linked to HIV itself, such as inflammation, reconstitution syndrome, low CD4, ART, and co‐infection with hepatitis B and C viruses. The risk of fractures in these individuals can be at least partially assessed by measurement of BMD and the Fracture Risk Assessment Tool (FRAX™). Only alendronate and zoledronic acid have been studied in HIV⁺ individuals; both show beneficial effects on BMD, although data on fracture reduction are not available. © 2018 The Authors. JBMR Plus Published by Wiley Periodicals, Inc. on behalf of American Society for Bone and Mineral Research.

Effect of antiretroviral therapy on bone turnover and bone mineral density in men with primary HIV-1 infection

Introduction

Previous studies indicate that human immunodeficiency virus (HIV)-infection and combination antiretroviral therapy (cART) can affect bone turnover. Furthermore, HIV-infected patients have lower bone mineral density (BMD) compared to a healthy reference population.

Objective

To evaluate the longitudinal effect of HIV-infection and cART on bone turnover markers (BTMs) and BMD in men with primary HIV-infection (PHI).

Design, methods

Thirty-five PHI-men were divided into two groups, those that received cART for the first time (n = 26) versus no-cART (n = 9). Dual-energy X-ray absorptiometry (DXA) was performed on femoral neck (FN), total hip (TH) and lumbar spine (LS) and BTMs (P1NP, alkaline phosphatase, osteocalcin, ICTP and CTX) were measured at baseline and follow-up.

Results

At baseline, the median CD4+ T-cell count was 455 cells/mm3 (IQR 320–620) and plasma viral load 5.4 log10 copies/mL (IQR 4.7–6.0) in the cART treated group, compared to 630 (IQR 590–910) and 4.8 (IQR 4.2–5.1) in the untreated group. The median follow-up time was 60.7 weeks (IQR 24.7–96.0). All BTMs, except ICTP, showed a significant increase during cART versus no changes of BTMs in the untreated group. FN and TH BMD showed a significant decrease in both groups. LS BMD did not change in both groups.

Conclusion

Bone turnover increased in PHI-men treated with cART which was accompanied by a decrease in FN and TH BMD. No increase of bone turnover was seen in untreated PHI-men. Our study suggests that cART results in increased bone turnover and decreased BMD of the hip in PHI-men.

Tenofovir-Associated Bone Adverse Outcomes among a US National Historical Cohort of HIV-Infected Veterans: Risk Modification by Concomitant Antiretrovirals

Introduction

Tenofovir disoproxil fumarate (TDF) has been associated with greater incidences of bone complications, which might be modified by some concomitantly administered antiretrovirals, possibly by their effect on tenofovir concentrations. We compared bone adverse outcomes among treatment-naïve HIV-infected US veterans initiating efavirenz (EFV)-containing TDF/emtricitabine (FTC) regimens versus those initiating non-EFV-containing TDF/FTC regimens.

Methods

Using national Veterans Health Administration clinical and administrative data sets, we identified a cohort of treatment-naïve HIV-infected veterans without bone disease who initiated therapy with TDF/FTC plus EFV, rilpivirine, elvitegravir/cobicistat, or ritonavir-boosted protease inhibitors in 2003–2015. The primary composite adverse bone outcome was the unadjusted incidence rate (IR) of osteoporosis, osteopenia, or fragility fracture (any hip, wrist, or spine fracture). To account for selection bias and confounding, we used inverse probability of treatment-weighted Cox proportional hazards regression models to calculate adjusted hazard ratios (HRs) for each outcome associated with EFV + TDF/FTC versus each non-EFV-containing TDF/FTC regimen.

Results

Of 33,048 HIV-positive veterans, 7161 initiated a TDF/FTC-containing regimen (mean age, 50 years; baseline CD4 < 200 cells/mm³, 33.3%; HIV-1 RNA > 100,000 copies/ml, 22.3%; mean follow-up, 13.0 months). Of these, 4137 initiated EFV- and 3024 non-EFV-containing regimens. Veterans initiating EFV- versus non-EFV-containing TDF/FTC regimens had a lower IR of the composite bone outcome (29.3 vs. 41.4 per 1000 patient-years), with significant risk reductions for this outcome [HR, 0.69; 95% confidence interval (CI), 0.58–0.83] and fragility fracture (HR, 0.59; 95% CI, 0.44–0.78).

Conclusion

EFV + TDF/FTC is associated with a lower risk of adverse bone outcomes compared with other TDF-containing regimens in the VHA.

Funding

Bristol-Myers Squibb.

Electronic supplementary material

The online version of this article (10.1007/s40121-018-0194-1) contains supplementary material, which is available to authorized users.

Tenofovir alafenamide as compared to tenofovir disoproxil fumarate in the management of chronic hepatitis B with recent trends in patient demographics

Tenofovir alafenamide (TAF) has recently been approved for chronic hepatitis B (CHB). It is more stable than tenofovir disoproxil fumarate (TDF) in the plasma and can provide similar efficacy with lower circulating concentration in patients with hepatitis B virus (HBV) infection. Areas covered: This synopsis will review the current anti-HBV standard practice and the changing epidemiology of CHB, specifically the controversies surrounding the renal and bone safety associated with TDF use in the context of an aging CHB population. We will review data from phase 3 registration trials, which demonstrated TAF was not inferior to TDF in antiviral efficacy for both HBeAg-positive and HBeAg-negative patients, while associated with less reduction in the estimated glomerular filtration rate and bone mineral density. Expert commentary: Current data supports the use of TAF as one of the first-line antiviral agents for general CHB patients without hepatic decompensation. However, more real-world data with long-term observation are needed to better define the role of TAF among other oral regimens. Additional studies are also needed to evaluate the efficacy and safety of TAF in special populations such as those with impaired hepatic function, existing impaired renal and/or bone function, and in pregnant women.

Protecting bone in long-term HIV positive patients receiving antiretrovirals

INTRODUCTION

As the population of people living with HIV ages, the increase in non-AIDs morbidities is expected to increase in parallel. Maintaining bone health in those with HIV will be an important area of focus for the HIV clinician to prevent the morbidity and mortality associated with fragility fractures, the principal clinical sequela of low bone mineral density (BMD). Rates of fractures and prevalence of low bone mineral density, a risk factor for future fragility fractures, are already increased in the HIV positive population.

AREAS COVERED

This review examines the strategies to maintain bone health in those living with HIV from screening through to managing those with established low BMD or fracture, including the role for choice of or modification of antiretroviral therapy to maintain bone health. Expert commentary: The increasing complexity of managing bone health in the age of succesful antiretroviral therapy and an aging patient population as well as future perspectives which may help achieve the long term aim of minimising the impact of low BMD in those with HIV are discussed and explored.

Switching from a ritonavir-boosted PI to dolutegravir as an alternative strategy in virologically suppressed HIV-infected individuals

Background

Switching from PIs to dolutegravir in virologically suppressed HIV-infected individuals has not been assessed.

Objectives

The principal aim was to assess the evolution of bone mineral density (BMD) when switching from a ritonavir-boosted PI to dolutegravir in HIV-infected patients with osteopenia or osteoporosis. The secondary objective was to assess the antiviral efficacy and safety of the switch therapy.

Methods

This randomized, multicentre study assessed changes in BMD, bone turnover markers, and antiviral efficacy and safety in 73 virologically suppressed patients with osteopenia/osteoporosis taking a ritonavir-boosted PI plus abacavir/lamivudine who were randomized to switch from PI to dolutegravir (DOLU group, n  =   37) or continue with a PI (PI group, n  =   36). Clinical Trials: NCT02577042.

Results

One and three patients from the DOLU and PI groups, respectively, withdrew prematurely (unrelated to treatment). At 48 weeks, 97.3% versus 91.7%, respectively, maintained viral suppression (snapshot analysis, ITT, M = F). No significant differences were seen between the groups in percentage change from baseline to week 48 in femoral ( P  =   0.56) and lumbar spine ( P  =   0.29) BMD, although lumbar spine BMD improved by 1.43% (-1.36; 2.92) in the DOLU group [0.12% (-2.83; 2.89) in the PI group]. Bone marker values did not vary significantly. At week 48, triglycerides were lower ( P  <   0.001) and HDL cholesterol higher ( P  =   0.027) in the DOLU group.

Conclusions

Dolutegravir + Kivexa ® was safe and well-tolerated in virologically suppressed patients receiving a PI-based regimen. The lipid profile was better, albeit without significant changes in BMD, probably because of the short follow-up.

Tenofovir and bone health

PURPOSE OF REVIEW

With continued improvements to the antiviral efficacy and tolerability of antiretroviral therapy, long-term safety of antiretroviral therapy has become paramount. Low bone mineral density and fragility fractures are more common in HIV-infected individuals than in the general population. The aims of this review are to describe potential mechanisms underlying the adverse effects of tenofovir on bone, clinical studies of tenofovir disoproxil fumarate (TDF) and bone, and more recent bone data on tenofovir alafenamide.

RECENT FINDING

Several studies have demonstrated an approximately 1-3% greater bone mineral density loss with TDF compared with other agents. Recent studies with tenofovir alafenamide have shown improved bone (and renal) safety with similar virologic efficacy when compared to TDF.

SUMMARY

Given these findings, TDF-containing regimens may be gradually replaced with non-TDF containing regimens for the treatment of HIV infection, especially in those at higher risk for fragility fracture.

Systematic review of renal and bone safety of the antiretroviral regimen efavirenz, emtricitabine, and tenofovir disoproxil fumarate in patients with HIV infection

BACKGROUND

Tenofovir disoproxil fumarate (TDF) is a component of many combinations of antiretroviral treatment (ART) regimens. Although potent and generally well tolerated, TDF may cause renal and bone toxicity. The magnitude of off-target side effects is proposed to be related to tenofovir plasma concentrations, which are affected by food and drug-drug interactions with concomitant antiretrovirals.

OBJECTIVE

To perform a systematic literature review and qualitatively report on renal and bone safety outcomes associated with efavirenz (EFV), emtricitabine (FTC), and TDF (EFV+FTC+TDF) ART.

METHODS

Embase and PubMed databases were searched for randomized clinical trials and observational cohort studies reporting on HIV treatment with EFV+FTC+TDF. Relevant articles were hand-searched for renal (Grade 3-4 serum creatinine/estimated glomerular filtration rate elevations, renal adverse events [AEs], discontinuation due to renal AEs, and urinary biomarkers) and bone outcomes (bone mineral density [BMD] reductions, bone turnover markers, and fracture), and results compiled qualitatively.

RESULTS

Of 337 retrieved articles, 29 reporting renal and 11 reporting bone outcomes met the review criteria. EFV+FTC+TDF was associated with a low frequency of renal AEs and treatment discontinuations due to renal AEs. Renal AEs were more frequent when TDF was taken with protease inhibitor (PI)- or cobicistat-containing ART. EFV+FTC+TDF was associated with reduced BMD and increased bone turnover markers, but BMD reductions were less than with PI-containing ART. No treatment-related bone fractures were identified.

CONCLUSIONS

EFV+FTC+TDF appeared to have a more favorable renal safety profile than TDF administered with a PI or cobicistat. BMD decreased with EFV+FTC+TDF, but no treatment-related fractures were identified.

Bone mineral density decline according to renal tubular dysfunction and phosphaturia in tenofovir-exposed HIV-infected patients

INTRODUCTION

The mechanisms underlying the effect of tenofovir disoproxil fumarate (TDF) on the decline of bone mineral density (BMD) have not been established, especially the effect of renal tubular dysfunction.

METHODS

Longitudinal study of 90 patients with two successive dual X-ray absorptiometry scans after evaluation of serum and urinary parameters (proteinuria, albuminuria, phosphaturia, uricosuria, glycosuria, β-2-microglobulin, and retinol-binding protein).

RESULTS

After a median of 38 months on TDF, osteopenia at spine and hip was observed in 49 and 48%, and osteoporosis in 9 and 2%, respectively. There was a lineal correlation between BMD at femoral neck and time on TDF (Spearman's rho = -0.27; P = 0.01). One or more tubular abnormalities were observed in 80% of cases (hyperphosphaturia, 50%). A lower BMD correlated with phosphaturia (r = -0.25; P = 0.03), even with phosphataemia within normal limits. In fact, patients with previous improvement in phosphaturia had better BMD at inclusion (Spearman's rho = -0.33; P < 0.01). A second dual X-ray absorptiometry, after a median of 40.8 months (33.8-45.1; 627.7 patients-year on TDF), showed additional BMD reduction at hip in 50% of cases (36% with bone loss >3%), a decline associated with phosphaturia (β, -0.31; P = 0.01) or number of tubular abnormalities (β, -0.41; P = 0.01), but also with use of boosted protease inhibitors (β, -0.47; P = 0.03) and BMD at inclusion (β, -0.33; P = 0.03).

CONCLUSION

Chronic abnormal phosphaturia explains, at least in part, progressive bone loss during TDF therapy. These data suggest that tubular dysfunction leads to an altered equilibrium between phosphataemia, phosphaturia, and bone as mechanism of progressive BMD decline.

A Single-dose Zoledronic Acid Infusion Prevents Antiretroviral Therapy-induced Bone Loss in Treatment-naive HIV-infected Patients: A Phase IIb Trial

BACKGROUND

Human immunodeficiency virus (HIV) infection and antiretroviral therapy (ART) are associated with bone loss leading to increased fracture rate among HIV-infected individuals. ART-induced bone loss is most intense within the first 48 weeks of therapy, providing a window for prophylaxis with long-acting antiresorptives.

METHODS

In a phase 2, double-blind, placebo-controlled trial, we randomized 63 nonosteoporotic, ART-naive adults with HIV initiating ART with atazanavir/ritonavir + tenofovir/emtricitabine to a single zoledronic acid (ZOL) infusion (5 mg) vs placebo to determine the efficacy of ZOL in mitigating ART-induced bone loss. Plasma bone turnover markers and bone mineral density (BMD) were performed at weeks 0, 12, 24, and 48 weeks. Primary outcome was change in C-terminal telopeptide of collagen at 24 weeks. Repeated-measures analyses using mixed linear models were used to estimate and compare study endpoints.

RESULTS

The ZOL arm had a 65% reduction in bone resorption relative to the placebo arm at 24 weeks (0.117 ng/mL vs 0.338 ng/mL; P < .001). This effect of ZOL occurred as early as 12 weeks (73% reduction; P < .001) and persisted through week 48 (57% reduction; P < .001). The ZOL arm had an 8% higher lumbar spine BMD at 12 weeks relative to the placebo arm (P = .003), and remained 11% higher at 24 and 48 weeks. Similar trends were observed in the hip and femoral neck.

CONCLUSIONS

A single dose of ZOL administered at ART initiation prevented ART-induced bone loss through the first 48 weeks of ART, the period when ART-induced bone loss is most pronounced. Validation of these results in larger multicenter randomized clinical trials is warranted.

CLINICAL TRIALS REGISTRATION

NCT01228318.