Tenofovir Disoproxil Fumarate Initiation Research Articles

Clinical characteristics and outcomes of patients with cirrhosis and hepatocellular carcinoma in The Gambia, west Africa: a prospective cohort study

Chronic liver disease is a major cause of premature death in sub-Saharan Africa. Efficacy of antiviral therapy among patients with hepatitis B virus (HBV)-related cirrhosis is not well established in Africa. We described the clinical characteristics and outcomes of patients with cirrhosis and hepatocellular carcinoma in The Gambia and assessed the impact of tenofovir disoproxil fumarate (TDF) on survival of HBV-infected patients with cirrhosis. In this prospective cohort study, we followed up adults who were consecutively diagnosed with cirrhosis or hepatocellular carcinoma between 2012 and 2015 in The Gambia, west Africa. Patients with chronic HBV infection and cirrhosis, without hepatocellular carcinoma, were offered TDF. Primary outcome was overall survival. To determine the effect of TDF on survival, we performed a Cox proportional hazard regression model with inverse probability of treatment weighting (IPTW) based on propensity score. Of 529 patients enrolled in this study, 336 patients (252 with hepatocellular carcinoma and 84 with cirrhosis) were analysed. Patients were predominantly male (253 [75%] men and 83 [25%] women), with a median age of 42 years (IQR 33-55). 276 (84%) of 327 of patients with data were positive for HBV biomarkers, 31 (10%) of 311 were positive for hepatitis C virus antibodies, and 22 (10%) of 223 were positive for hepatitis D virus antibodies. 64% of patients with hepatocellular carcinoma had multifocal tumour, with a median size of 7·5 cm (IQR 5·4-10·8). 173 patients with hepatocellular carcinoma and 70 patients with cirrhosis were included in the survival analysis. Median survival was 1·5 months (95% CI 1·1-2·0) in patients with hepatocellular carcinoma and 17·1 months (11·2-24·0) in patients with cirrhosis (log-rank p<0·0001). In patients with hepatocellular carcinoma, ascites (hazard ratio [HR] 1·78, 95% CI 1·21-2·60), partial or complete portal thrombosis (HR 2·61, 1·58-4·30), and platelet count (HR 1·80, 1·19-2·70) were independent predictive factors of mortality at baseline. In HBV-infected patients with cirrhosis, median turnaround time between cirrhosis diagnosis and TDF initiation was 4·9 months (IQR 3·2-7·3). In IPTW analysis, TDF treatment was associated with improved survival in patients with HBV-related cirrhosis (adjusted HR 0·14, 0·06-0·34; p<0·0001). These results highlight poor survival of patients with cirrhosis or hepatocellular carcinoma as well as the effectiveness of TDF in reducing the premature mortality of patients with cirrhosis and HBV infection. Interventions for early diagnosis and treatment of cirrhosis as well as screening programmes for hepatocellular carcinoma are urgently required in Africa. European Commission and Medical Research Council UK. For the French translation of the abstract see Supplementary Materials section.

S3176 Tenofovir Disoproxil Fumarate-Related Metabolic Syndrome and Steatohepatitis in a Case of Chronic Hepatitis B

Introduction: Tenofovir disoproxil fumarate (TDF) is a nucleotide analog used in the treatment of chronic hepatitis B virus infection (HBV). TDF is considered to have no direct hepatotoxicity. Herein we present a patient with HBV developing liver test abnormalities and biopsy-proven steatohepatitis (SH) after starting TDF, and the resolution of liver tests and SH after switching TDF to entecavir (ETV). Case Description/Methods: A 48-year-old female patient was admitted to our clinic with positive HBsAg and HBV-DNA level of 21600 copies/mL. Her Anti-HBe was positive and Anti-HDV was negative. Abdominal ultrasonography revealed 2 cm hepatomegaly; her AST was 74 U/L (5-40 U/L) and ALT 125 U/L (10-40 U/L). Her BMI was within normal limits, she had no comorbidities and was not on any medication. Her lipid panel was within the normal range. She was prescribed 245 mg/day TDF, and was scheduled for regular clinical follow-up. Six months later, her AST was 113 U/L, ALT 148 U/L, and her HBV-DNA was negative. The patient was advised to follow-up closely. Eighteen months after the initiation of TDF, her AST increased to 211 U/L and ALT to 216 U/L. Her HbA1c was 6.1% and HOMA-IR was 4.0. MRI showed fat accumulation in the liver, and a liver needle biopsy was performed. Histological evaluation revealed grade 2 steatosis with moderate ballooning degeneration and stage 3/4 fibrosis (Figure 1). Autoimmune serologies including antinuclear antibody and anti-smooth muscle antibody were negative, and ceruloplasmin phenotype was normal. The causation of TDF was hypothesized. TDF was stopped, and ETV 0.5 mg/day was initiated. Her follow-up at month 3 revealed a decreased trend in transaminase levels. The patient lost to follow-up for 2 years, but she used ETV regularly. Her control HbA1c was 5.5% at this last visit and a control abdominal ultrasonography showed no fat accumulation. Discussion: While it is known that TDF co-administration with other nucleoside analogs (e.g., didanosine, stavudine) can cause fatty infiltration of the liver, we present a rare case of metabolic syndrome and SH related with TDF monotherapy. Despite some reports suggesting tenofovir, specifically tenofovir alafenamide, might be associated with adverse metabolic changes in patients with HIV, our patient with HBV developed these changes while she was on TDF. We show that hepatic steatosis associated with TDF can be reversible with the medication change to ETV.Figure 1.: A: Hematoxylin-eosin staining shows 50% steatosis (grade 2), portal and lobular inflammation and moderate hepatocyte ballooning. B: Masson-trichrome staining shows portocentral and pericellular fibrosis (stage 3/4).

Tenofovir-based combination therapy or monotherapy for multidrug-resistant chronic hepatitis B: Long-term data from a multicenter cohort study.

The treatment of multidrug-resistant (MDR) chronic hepatitis B (CHB) is challenging. Herein, we report a multicenter prospective cohort study for the evaluation of tenofovir disoproxil fumarate (TDF)-based therapy for MDR CHB in a real-life setting. The inclusion criteria comprised patients with resistance to more than two nucleos(t)ide analogue (NA) classes and hepatitis B virus (HBV) DNA level of ≥200IU/mL. The primary end-point was virologic response (VR), defined as undetectable HBV DNA (<20IU/mL) after 60months. A total of 236 patients met the inclusion criteria. The mean HBV DNA level was 4.16±1.44 log IU/mL; 26.7% of patients had liver cirrhosis. Before the initiation of TDF, 33.5%, 44.9% and 21.6% of patients had mutations resistant to L-NA+adefovir, L-NA+entecavir (ETV) and L-NA+adefovir+ETV, respectively. A total of 184 patients received TDF-based combination therapy [TDF+ETV (n=178) or TDF+L-NA (n=6)], and 52 patients received TDF monotherapy. In the entire cohort, the VR rates were 77.2%, 89.9% and 92.2% at 12, 36 and 60months, respectively. The VR rates were not significantly different between the combination therapy and the monotherapy group after 12 (76.2% vs 80.4%, P=.533), 36 (89.8% vs 90.3%, P=1.000) or 60 (92.9% vs 87.5%, P=.499) months. Also, there was no significant difference in the cumulative VR rates for 5years between the treatment groups (P=.910). Newly developed antiviral resistance was not observed. TDF-based therapy was effective for the treatment of MDR CHB. The efficacy of TDF monotherapy was not different from that of the TDF-based combination therapy.

Longitudinal change in bone mineral density among Chinese individuals with HIV after initiation of antiretroviral therapy.

Persons living with HIV (PLWH) are at increased risk for osteoporosis and fracture. Tenofovir disoproxil fumarate (TDF) has been associated with higher rates of bone mineral density (BMD) loss, osteoporosis, and fracture. Few studies have studied the impact among PLWH in Asia. We analyzed retrospectively patients from the outpatient HIV clinic of a large tertiary hospital in Beijing, China, from March 2007 to May 2016. Patients who had dual-energy X-ray absorptiometry testing prior to antiretroviral initiation and at 48 and/or 96weeks after initiation were included in this analysis. A total of 136 patients were included (mean age 36.0 ± 10.6years) and over 90% participants were male and Han Chinese ethnicity. We observed greater declines in BMD at the spine from baseline to week 48 (-2.94% vs. -0.74%) and at the hip from baseline to week 96 (-4.37% vs. -2.34%) in the TDF group compared with the non-TDF group. With regard to HIV-specific parameters, longer duration since HIV diagnosis and undetectable viral load over time were associated with lower BMD at the hip [relative risk (RR) 0.97, 95% confidence index (CI) (0.95, 0.99) per 1year increase and RR 0.96, 95%CI (0.94, 0.99), respectively] and femoral neck [RR 0.97, 95%CI (0.95, 0.99) per 1year increase and RR 0.97, 95%CI (0.95, 0.998), respectively] over 96weeks. This is the first study to report changes in BMD among PLWH after initiation of TDF-based antiretroviral therapy in China. Our findings provide important knowledge for the long-term clinical management of PLWH from this region.

Early Start Of Tenofovir Treatment Achieves Better Viral Suppression In Pregnant Women With A High HBV Viral Load: A Real-World Prospective Study.

PurposeTo investigate whether tenofovir disoproxil fumarate (TDF) treatment that started from the second trimester had an advantage over TDF treatment that started from the third trimester.Patients and methodsTwenty 35-year-old pregnant women with hepatitis B virus (HBV) DNA >2×106 IU/mL were prospectively enrolled in this study. All participants were divided into two subgroups: the second trimester group who started TDF treatment at 24–27 weeks and the third trimester group who started TDF treatment at 28–30 weeks. The primary outcome was the change in serum HBV DNA level from baseline to delivery. Each parameter was tested every 4 weeks from TDF initiation to 3 months postpartum.ResultsThere were 80 pregnant women in the second trimester group and 49 pregnant women in the third trimester group. The decline in HBV DNA from baseline to delivery was more obvious in the second trimester group (4.8±1.2 log10 IU/mL) than that in the third trimester group (4.3±1.1 log10 IU/mL, p=0.041). The downward shift of haemoglobin (HB) from baseline to delivery was greater in the second trimester group (10.6±10.7 g/L) than in the third trimester group (6.3±12.3 g/L, p=0.041). The decline in HBV DNA from baseline to delivery was linearly related to the start of TDF treatment from the second trimester (β=0.50 and 95% CI: 0.26–0.75, p<0.001). There were no significant differences between the two groups regarding HBV serologic markers and safety indicators.ConclusionStarting TDF treatment from the second trimester achieved better viral suppression than starting TDF treatment from the third trimester in highly viraemic pregnant women without increasing additional adverse reactions. HB level needed frequent monitoring during treatment to avoid anaemia.Registry numberClinical Trial No. NCT02719808.

Incidence of hepatocellular carcinoma in HIV/HBV-coinfected patients on tenofovir therapy: Relevance for screening strategies

Robust data on hepatocellular carcinoma (HCC) incidence among HIV/hepatitis B virus (HBV)-coinfected individuals on antiretroviral therapy (ART) are needed to inform HCC screening strategies. We aimed to evaluate the incidence and risk factors of HCC among HIV/HBV-coinfected individuals on tenofovir disoproxil fumarate (TDF)-containing ART in a large multi-cohort study. We included all HIV-infected adults with a positive hepatitis B surface antigen test followed in 4 prospective European cohorts. The primary outcome was the occurrence of HCC. Demographic and clinical information was retrieved from routinely collected data, and liver cirrhosis was defined according to results from liver biopsy or non-invasive measurements. Multivariable Poisson regression was used to assess HCC risk factors. A total of 3,625 HIV/HBV-coinfected patients were included, of whom 72% had started TDF-containing ART. Over 32,673 patient-years (py), 60 individuals (1.7%) developed an HCC. The incidence of HCC remained stable over time among individuals on TDF, whereas it increased steadily among those not on TDF. Among individuals on TDF, the incidence of HCC was 5.9 per 1,000 py (95% CI 3.60-9.10) in cirrhotics and 1.17 per 1,000 py (0.56-2.14) among non-cirrhotics. Age at initiation of TDF (adjusted incidence rate ratio per 10-year increase: 2.2, 95% CI 1.6-3.0) and the presence of liver cirrhosis (4.5, 2.3-8.9) were predictors of HCC. Among non-cirrhotic individuals, the incidence of HCC was only above the commonly used screening threshold of 2 cases per 1,000 py in patients aged >45 years old at TDF initiation. Whereas the incidence of HCC was high in cirrhotic HIV/HBV-coinfected individuals, it remained below the HCC screening threshold in patients without cirrhosis who started TDF aged <46 years old. We investigated the incidence of hepatocellular carcinoma in HIV/hepatitis B virus-coinfected individuals from a large multi-cohort study in Europe. Over 32,673 patient-years, 60 individuals (1.7%) developed hepatocellular carcinoma. The incidence of hepatocellular carcinoma remained low in patients without cirrhosis, who started on tenofovir disoproxil fumarate when aged <46 years old.

Tenofovir disoproxil fumarate initiation and changes in urinary biomarker concentrations among HIV-infected men and women.

Urinary biomarkers of kidney injury may have potential to identify subclinical injury attributable to tenofovir disoproxil fumarate (TDF) toxicity. This observational study included 198 HIV-infected participants from the Multicenter AIDS Cohort Study and the Women's Interagency HIV Study, who initiated TDF between 2009 and 2015 and had urine samples collected at baseline before and after TDF initiation. We used linear mixed-effects models controlling for urine creatinine and time on TDF to evaluate the effects of TDF initiation on changes in 14 urinary biomarkers. Within 1 year after TDF initiation, concentrations of trefoil factor 3 [+78%; 95% confidence interval (CI) +38%, +129%), alpha-1 microglobulin (α1m) (+32%; 95% CI +13%, +55%), clusterin (+21%; 95% CI +6%, +38%), uromodulin (+19%; 95% CI +4%, +36%), and kidney injury molecule-1 (KIM-1) (+13%; 95% CI +1%, +26%) significantly increased, whereas interleukin-18 (IL-18) significantly decreased (-13%, 95% CI -7%, -25%). Subsequent to the first year of TDF use, biomarker concentrations stabilized, and these changes were not statistically significant. When stratifying by baseline viremia (HIV-1 RNA < vs. ≥80 copies/ml), concentration changes for most biomarkers during the first year of TDF use were greater among aviremic vs. viremic participants, with significant differences in α1m (+80 vs. +22%), KIM-1 (+43 vs. +10%), beta-2 microglobulin (+83 vs. -10%), YKL-40 (+33 vs. -5%), and IL-18 (+20 vs. -27%). TDF initiation was associated with substantial changes in urinary biomarkers of kidney injury within the first year of use, particularly among aviremic participants. A urinary biomarker panel may be a clinically useful tool to detect and monitor the heterogeneous effects of TDF on the kidney.

Inflammation status in HIV-positive individuals correlates with changes in bone tissue quality after initiation of ART.

The mechanisms behind ART-induced bone changes in HIV-infected patients are poorly known. We aimed to analyse changes in inflammatory and bone markers in HIV after tenofovir disoproxil fumarate initiation, and the associations with changes in the bone strength parameters. HIV-positive participants starting tenofovir disoproxil fumarate-based ART underwent dual-energy X-ray absorptiometry (QDR 4500 SL®, Hologic, Waltham, MA, USA) for bone mineral density (BMD), a microindentation test (OsteoProbe®, Active Life Scientific, Santa Barbara, CA, USA) for bone quality [bone material strength index (BMSi)] and phlebotomy at baseline and 48 weeks after ART. A panel of inflammatory biomarkers and bone turnover markers were measured by ELISA. HIV-negative controls underwent identical procedures once. Values are expressed as medians and IQRs, and non-parametric tests were used to perform the analysis. Twenty HIV-infected individuals and 20 HIV-negative control individuals were matched in terms of age and gender. HIV individuals showed higher levels of inflammatory markers. We found no differences in bone turnover markers. HIV-positive individuals presented lower BMSi values at baseline compared with controls [86 (83-90) versus 89 (88-93), respectively; P = 0.034]. We found no difference in BMD (at either of the sites evaluated). BMSi tended to increase with treatment. IL-1β at baseline was positively correlated with changes in BMSi after ART (rho = 0.564, P = 0.014). Baseline levels of sclerostin tended to be negatively correlated with changes in BMSi (rho = -0.402, P = 0.097). We found a negative correlation between time since HIV diagnosis and changes in BMSi (rho = -0.466, P = 0.04). We observed a correlation between changes in bone quality and the inflammatory environment in HIV-positive individuals. Moreover, among the underlying mechanisms we highlight the Wnt pathway as having a potentially significant role in ART bone quality recovery.

2258. Clinical Predictors of Acute Kidney Injury in HIV Infected Patients Treated With Tenofovir Disoproxil Fumarate (TDF)

BackgroundTDF is a nucleotide reverse transcriptase inhibitor used in the management of HIV, Hepatitis B, and in pre-exposure prophylaxis. TDF is potentially toxic to renal proximal tubules leading to overt nephrotoxicity in some recipients. Previous studies have identified risk factors for renal dysfunction in male veterans and Asia. It is unclear if these results generalize to female patients and other ethnic groups.MethodsWe conducted a retrospective review of HIV-infected patients treated with TDF in a Ryan White funded clinic at the University of Kentucky which provides HIV care to ~1,600 patients from central and eastern Kentucky. To be included,subjects had to be at least 18 years of age and started a TDF containing regimen between January 1, 2012 and December 31, 2016. Follow-up was through March 2017. We collected demographic and relevant clinical data from the Electronic Medical Record. Acute kidney injury (AKI) was defined as a ≥50% rise in serum creatinine after TDF initiation. Primary outcome was time to AKI using Kaplan–Meier (KM) and Cox proportional hazards analyses.ResultsThe 660 subjects meeting inclusion criteria were largely male (79.8%) and ethnically white (69.7%), African-American (22.6%), and Hispanic (6.8%). Average age was 41.2 years (SD 11.9 years). During the study period 88 subjects developed AKI. In KM analyses, risk of AKI was greater for females (P = 0.041), upper tertile of age (>47.5 years, P = 0.024), and among patients with hypertension (P = 0.001), diabetes mellitus (DM) (P = 0.02) having detectable HIV viremia (P = 0.0004) or Hepatitis C viremia (P = 0.00002). In the Cox model, female sex (hazard ratio [HR]=1.68, P = 0.035), upper tertile of age (HR=1.94, P = 0.026), HTN (HR=1.70, P = 0.023), unsuppressed HIV viral load (HR=2.75, P = 0.00008), and Hepatitis C viremia (HR=2.65, P = 0.0002) increased risk of AKI. Neither ethnicity nor DM were associated with AKI.ConclusionThe factors associated with greatest AKI risk during TDF treatment were hepatitis C viremia and HIV viremia. Older age, female sex, and hypertension were significantly associated with increased AKI. We found neither DM nor ethnicity were independently associated with AKI.Disclosures All authors: No reported disclosures.

A retrospective analysis of weight changes in HIV-positive patients switching from a tenofovir disoproxil fumarate (TDF)- to a tenofovir alafenamide fumarate (TAF)-containing treatment regimen in one German university hospital in 2015\u20132017

PurposeTo determine whether changing from a tenofovir disoproxil fumarate (TDF)- to a tenofovir alafenamide fumarate (TAF)-containing regimen is correlated with weight changes in a human immunodeficiency virus (HIV)-positive adult cohort.MethodsRetrospective analysis was conducted of data gathered from routine care in a university hospital in Munich, Germany, between July 2015 and June 2017. Data from patients’ charts were extracted and a two-step approach was applied. First, weight/BMI progression within 1 year after initiation of either TDF or TAF was compared. Subsequently, weight measurements within subjects changing from a TDF- to a TAF-containing antiretroviral regimen were analyzed by means of a repeated measurements general linear model.ResultsAfter 360 days of initiating TAF, patients showed a mean (± standard deviation) percentual weight increase of 3.17 ± 0.21, whereas after 360 days of initiating TDF, patients only showed a mean (± standard deviation) percentual weight increase of 0.55 ± 0.17. The repeated measurements general linear model for within-subjects design showed a statistically significant correlation in weight after changing from a TDF to a TAF containing antiretroviral regimen. The weight difference between the two measurements while on TDF was not statistically significant, but every measure after switching to TAF was significantly higher than the previous.ConclusionChanging from a TDF- to a TAF-containing regimen is correlated with weight gain in this retrospectively analyzed real-world cohort in Munich, Germany.

Association of Urinary Biomarkers of Kidney Injury with Estimated GFR Decline in HIV-Infected Individuals following Tenofovir Disoproxil Fumarate Initiation.

Tenofovir disoproxil fumarate (tenofovir) is associated with elevated concentrations of biomarkers of kidney damage and dysfunction in individuals with HIV. The relationship of these kidney biomarkers with longitudinal kidney function decline is unknown. We evaluated associations of 14 urinary biomarkers of kidney injury with changes in eGFR among 198 men and women with HIV who initiated tenofovir between 2009 and 2015 in the Multicenter AIDS Cohort Study and Women's Interagency HIV Study. Urinary biomarkers included albumin-to-creatinine ratio, α-1-microglobulin, β-2-microglobulin, cystatin C, kidney injury molecule-1 (KIM-1), IL-18, neutrophil gelatinase-associated lipocalin (NGAL), clusterin, osteopontin, uromodulin, monocyte chemoattractant protein-1, EGF, trefoil factor 3, and chitinase 3-like protein 1. We used multivariable linear mixed-effect models controlling for demographics, traditional kidney disease risk factors, and HIV-related risk factors to evaluate associations of baseline biomarkers with first-year changes in eGFR, and associations of year 1 and first-year change in biomarkers with changes in eGFR from year 1 to year 3. We used the least absolute shrinkage and selection operator method to identify a parsimonious set of biomarkers jointly associated with changes in eGFR. Median eGFR before tenofovir initiation was 103 (interquartile range, 88-116) ml/min per 1.73 m2. During the first year of tenofovir use, eGFR decreased on average by 9.2 (95% confidence interval, 6.5 to 11.9) ml/min per 1.73 m2 and was stable afterward (decrease of 0.62; 95% confidence interval, -0.85 to 2.1 ml/min per 1.73 m2 per year). After multivariable adjustment, higher baseline β-2-microglobulin, KIM-1, and clusterin were associated with larger first-year eGFR declines, whereas higher baseline uromodulin was associated with a smaller eGFR decline. First-year increase in urinary cystatin C and higher year 1 IL-18 were associated with larger annual eGFR declines from year 1 to year 3. The parsimonious models identified higher pre-tenofovir clusterin and KIM-1, lower pre-tenofovir uromodulin, and higher year 1 IL-18 as jointly associated with larger eGFR declines. Urinary biomarkers of kidney injury measured before and after tenofovir initiation are associated with subsequent changes in eGFR in individuals with HIV. This article contains a podcast at https://www.asn-online.org/media/podcast/CJASN/2018_08_28_CJASNPodcast_18_9_S.mp3.

Bone mineral density reductions after tenofovir disoproxil fumarate initiation and changes in phosphaturia: a secondary analysis of ACTG A5224s

It is unknown if the greater reductions in bone mineral density (BMD) associated with initiation of tenofovir disoproxil fumarate compared with abacavir in previously untreated HIV-infected participants in the ACTG A5224s clinical trial were associated with potentially worsening tenofovir-related phosphaturia. We correlated changes in BMD at the hip and spine with changes in phosphaturia [transtubular reabsorption of phosphorus (TRP) and tubular maximum phosphate reabsorption per glomerular filtration rate (TmP/GFR)] from entry through week 96 in those initiating tenofovir ( n = 134) versus abacavir ( n = 135) with efavirenz or atazanavir/ritonavir in A5224s. We also correlated changes in BMD with tenofovir AUC measured between weeks 4 and 24. Changes in TRP and TmP/GFR through week 96 between the tenofovir and abacavir arms were not significantly different (both P ≥ 0.70) and did not differ with use of efavirenz versus atazanavir/ritonavir. There were no significant correlations between changes in either TRP or TmP/GFR and with either hip or spine BMD in the tenofovir arms. Tenofovir AUC was significantly correlated with changes in hip BMD, but not spine BMD, at week 24 ( r = -0.22, P = 0.028) and week 48 ( r = -0.26, P = 0.010), but not at week 96 ( r = -0.14, P = 0.18). Changes in phosphaturia were not different between the tenofovir and abacavir arms in A5224s. Changes in hip and spine BMD with tenofovir were not related to changes in phosphaturia. However, tenofovir exposure was weakly associated with changes in hip BMD through week 48.

Renal Dysfunction during Tenofovir Use in a Regional Cohort of HIV-Infected Individuals in the Asia-Pacific.

BackgroundIn resource-limited settings, routine monitoring of renal function during antiretroviral therapy (ART) has not been recommended. However, concerns for tenofovir disoproxil fumarate (TDF)-related nephrotoxicity persist with increased use.MethodsWe investigated serum creatinine (S-Cr) monitoring rates before and during ART and the incidence and prevalence of renal dysfunction after starting TDF by using data from a regional cohort of HIV-infected individuals in the Asia-Pacific. Time to renal dysfunction was defined as time from TDF initiation to the decline in estimated glomerular filtration rate (eGFR) to <60 ml/min/1.73m2 with >30% reduction from baseline using the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation or the decision to stop TDF for reported TDF-nephrotoxicity. Predictors of S-Cr monitoring rates were assessed by Poisson regression and risk factors for developing renal dysfunction were assessed by Cox regression.ResultsAmong 2,425 patients who received TDF, S-Cr monitoring rates increased from 1.01 to 1.84 per person per year after starting TDF (incidence rate ratio 1.68, 95%CI 1.62–1.74, p <0.001). Renal dysfunction on TDF occurred in 103 patients over 5,368 person-years of TDF use (4.2%; incidence 1.75 per 100 person-years). Risk factors for developing renal dysfunction included older age (>50 vs. ≤30, hazard ratio [HR] 5.39, 95%CI 2.52–11.50, p <0.001; and using PI-based regimen (HR 1.93, 95%CI 1.22–3.07, p = 0.005). Having an eGFR prior to TDF (pre-TDF eGFR) of ≥60 ml/min/1.73m2 showed a protective effect (HR 0.38, 95%CI, 0.17–0.85, p = 0.018).ConclusionsRenal dysfunction on commencing TDF use was not common, however, older age, lower baseline eGFR and PI-based ART were associated with higher risk of renal dysfunction during TDF use in adult HIV-infected individuals in the Asia-Pacific region.

Urinary β2 microglobulin can predict tenofovir disoproxil fumarate-related renal dysfunction in HIV-1-infected patients who initiate tenofovir disoproxil fumarate-containing antiretroviral therapy

In nephrotoxicity induced by tenofovir disoproxil fumarate (TDF), tubular dysfunction precedes the decline in GFR, suggesting that tubular markers are more sensitive than estimated glomerular filtration rate (eGFR). The hypothesis that urinary β2 microglobulin (β2 M), a tubular function marker, can predict TDF-renal dysfunction in HIV-1-infected patients was tested. A single-center observational study. The inclusion criteria were: HIV-1-infected patients who started TDF-containing antiretroviral therapy from 2004 to 2013, urinary β2 M after and closest to the day of TDF initiation within 180 days (termed 'β2 M after TDF') was measured. The associations between 'β2 M after TDF' and four renal end points (>10 ml/min per 1.73 m decrement in eGFR relative to baseline, >20 decrement, >25% decrement, and eGFR < 60) were estimated with logistic regression model. The association between 'β2 M after TDF' and longitudinal changes in eGFR after initiation of TDF was estimated with a mixed-model. A total 655 study patients were analyzed (96% men, median age 38, median CD4 238 cells/μl, 63% treatment naïve). The median baseline eGFR was 117 ml/min per 1.73 m (IQR 110-125), and the median duration of TDF use was 3.32 years (IQR 2.02-5.31). 'β2 M after TDF' was significantly associated with more than 20 decrement in eGFR (P = 0.024) and more than 25% decrement (P = 0.014), and was marginally associated with eGFR less than 60 (P = 0.076). It was also significantly associated with the longitudinal eGFR after initiation of TDF (P < 0.0001). 'β2 M after TDF' of 1700 μg/l was identified as the optimal cutoff value for the prediction of longitudinal eGFR. Urinary β2 M measured within 180 days after initiation of TDF predicts renal dysfunction related to long-term TDF use.

Prevalence and significance of proximal renal tubular abnormalities in HIV-infected patients receiving tenofovir.

Patients receiving tenofovir, disoproxil, fumarate (TDF) had an increased prevalence of proximal renal tubular dysfunction (PRTD), but contributing factors and its clinical significance remain controversial. Cross-sectional evaluation of different urinary parameters (proteinuria, albuminuria, phosphaturia, uricosuria, glycosuria) in 200 HIV-infected patients receiving TDF, 26 following TDF discontinuation, and 22 never treated with TDF, included in a prospective cohort study. PRTD was defined as two or more tubular abnormalities. After a median of 65 months (interquartile range, 42.7-84.7), at least one tubular alteration was found in 72% of patients, mostly proteinuria (42, 50, and 14% in current, previous and never TDF use; P=0.02) and phosphaturia (46, 42, and 14%; respectively, P < 0.01). PRTD was found in 63 patients (32%) receiving TDF, ranging from 14 to 46% according to concomitant hepatitis C virus coinfection, diabetes mellitus or hypertension arterial, in contrast with six (23%) following TDF discontinuation, and zero cases in no TDF-treated patients. The use of TDF [odds ratio (OR) 13.2; 95% confidence interval (CI) 1.4-22.7; P = 0.01], cumulative time on combination antiretroviral therapy (OR 1.011; 95% CI 1.07-1.019 per month; P = 0.01), and baseline estimated glomerular filtration rate (eGFR, OR 0.97; 95% CI 0.94-0.99 per ml/min per 1.73 m higher; P = 0.04) were associated with PRTD. The number of tubular abnormalities was linearly associated with eGFR decline since TDF initiation (β-coefficient -0.15, P = 0.02), together with age (-0.18; P = 0.01), baseline eGFR (0.49, P = 0.01), diabetes mellitus (-0.19, P = 0.02), and time on TDF (-0.23; P = 0.01). The use of TDF leads to an increased rate of tubular dysfunction, and modulated by age, baseline eGFR, and classical factors, is associated with kidney function decline.

Tenofovir monotherapy for hepatitis B after 1 year does not produce renal dysfunction, but is associated with hyperparathyroidism not related to vitamin D.

Viral hepatitis B (VHB) represents a major public health problem. Studies from HIV multidrug patients have associated the use of tenofovir disoproxil fumarate (TDF) with renal dysfunction and phosphate wasting. The aim of this study was to examine the effect of year-long TDF monotherapy on renal function in VHB patients. We evaluated adult patients diagnosed with VHB before treatment initiation (T0), and after 3 and 12 months (T3 and T12) of TDF initiation. Estimated glomerular filtration rate (eGFR) was estimated by serum cystatin C and creatinine. In addition, urinary electrolytes and tubular biomarkers (cystatin C, β2-microglobulin and neutrophil gelatinase-associated lipocalin) were analyzed, as well as parathyroid hormone (PTH) and 25(OH)vitamin D levels. After 1 year, 32 patients completed the study, 22 (68.7%) men and 12 (37.5%) Whites, mean age 44.1±12.0 years. We found that serum electrolytes were similar at baseline and 3 or 12 months after initiation of TDF monotherapy. In addition, urinary fractional excretions of electrolytes as well as proteinuria, albuminuria, urinary β2-microglobulin, and urinary cystatin C showed no significant differences across the treatment timeline. There were also no statistical differences in the eGFR. There was a statistically significant increase in the PTH (Friedman's test, P=0.012), but the 25(OH)vitamin D levels were in the normal range in the beginning and did not change at the follow-up. Moreover, there was no correlation between the initial levels of vitamin D and the corresponding increases in the PTH values. If used as monotherapy in hepatitis B patients for a 12-month period, TDF is not associated with changes in either eGFR or a panel of urinary biomarkers. Serum and urinary electrolytes also remained unchanged. Of note, a significant increase in the PTH was found, although not related to the 25(OH)vitamin D initial status.

Effectiveness and Safety of Tenofovir Disoproxil Fumarate in Chronic Hepatitis B: A 3-Year Prospective Field Practice Study in Germany.

Multiple clinical trials have demonstrated the efficacy and safety of tenofovir disoproxil fumarate (TDF) in chronic hepatitis B (CHB). However, long-term efficacy and safety data for TDF in real-life clinical practice are limited. Prospective German field practice study in CHB-mono-infected patients. Patients were TDF-naïve but could have been treated previously with other HBV antivirals. Efficacy analysis included 400 patients; 301 (75%) completed 36months of TDF treatment. Both treatment-naïve and treatment-experienced patients showed a rapid decline in HBV DNA within 3months of TDF initiation. After 36months, HBV DNA<69IU/mL was achieved by 91% of treatment-naïve patients (90 and 92% in hepatitis B "e" antigen [HBeAg]-positive and [HBeAg]-negative, respectively) and 96% of treatment-experienced patients (93 and 97%, respectively). Three patients experienced virologic breakthrough, all with reported non-compliance. Overall, 5.7% HBeAg-positive and 2.2% HBeAg-negative patients lost hepatitis B surface antigen. Safety data were consistent with the known TDF safety profile; the most commonly reported adverse events possibly related to TDF were fatigue (2.0%) and headache (2.0%). Few patients (1.3%) experienced renal-related adverse reactions. Creatinine clearance remained relatively stable over time; patients responded favorably where TDF was dose adjusted per label for decreased creatinine clearance. TDF showed a favorable tolerability profile and induced rapid and sustained suppression of HBV DNA in patients with CHB treated for up to 3years in routine clinical practice, irrespective of treatment history. Efficacy and safety in this heterogeneous patient population were consistent with data from clinical trials.

The impact of tenofovir disoproxil fumarate on kidney function: four-year data from the HIV-infected outpatient cohort.

IntroductionWith improvements in survival and disease progression in the era of combined antiretroviral therapy, complications such as kidney disease are becoming increasingly prevalent in HIV-infected patients. Tenofovir disoproxil fumarate (TDF) has been associated with nephrotoxicity, including decline in glomerular filtration rate, proximal tubular damage and acute kidney injury.ObjectiveCharacterize kidney safety of TDF-containing antiretroviral treatment (ART) regimens in HIV-infected patients.MethodsNon-controlled, observational, retrospective study was based on the clinical files registry of HIV patients who started TDF between January and December 2008. We assessed outpatients followed at a single Portuguese center. Demographic, clinical, virological and immunological data at baseline were collected. Serum creatinine, estimated glomerular filtration rate (eGFR) and creatinine clearance (CrCL) were assessed at baseline, after six months and every year up to four years. CrCL and eGFR were calculated by Cockroft–Gault and Modification of Diet in Renal Disease equations, respectively.ResultsA total of 176 patients (71.6% males) with a mean age of 43 years were enrolled. Ninety-six (52%) were ART-naive patients at TDF initiation. At baseline 12.5% had hypertension, 4% diabetes, 25% chronic hepatitis C and 9% chronic hepatitis B infections; 58% had normal renal function (eGFR ≥90 ml/min/1.73 m2), 36% had mild (eGFR 60-89 ml/min/1.73 m2) renal dysfunction and 2.3% had moderate (eGFR 30-59 ml/min/1.73 m2) renal dysfunction at initiation of TDF. Eighty-three (47%) patients were on protease inhibitors and the remaining on NNRTIs containing regimens. During 48 months follow-up, 5% experienced moderate renal dysfunction and 1.7% severe renal dysfunction. Twenty-one (12%) patients met the definition criteria of rapid decline of renal function (annual decline of eGFR ≥3 ml/min/1.73 m2 in two consecutive years). The development of kidney events was associated with age above 50 years, presence of comorbidities and advanced stage HIV infection (p>0.05 in univariate analysis).ConclusionsThese data reveal a favourable renal safety profile of TDF, during a four-year follow-up. Screening for kidney disease markers, regular follow-up and control and prevention of risk factors for renal failure are crucial for adequate management of HIV-infected patients.

Fanconi Syndrome Accompanied by Renal Function Decline with Tenofovir Disoproxil Fumarate: A Prospective, Case-Control Study of Predictors and Resolution in HIV-Infected Patients

ObjectiveThe predictors of Fanconi syndrome (FS) accompanied by renal function decline with use of the antiretroviral tenofovir disoproxil fumarate (TDF) have not been assessed. In addition, the natural history of renal recovery from FS after TDF discontinuation is not well-described.DesignWe prospectively enrolled HIV-infected patients receiving TDF with newly identified FS (defined as at least two markers of proximal tubulopathy and either a >25% decline in creatinine clearance (CrCl) from pre-TDF values or a CrCl <60 mL/min in those without a known pre-TDF CrCl) in a multicenter observational study. These case participants were matched 1∶2 to controls; characteristics between the two groups were compared. Case participants with known pre-TDF CrCl values were then followed over 48 weeks to assess renal recovery.ResultsNineteen cases and 37 controls were enrolled. In multivariable analysis, previous or concurrent use of lopinavir/ritonavir [OR 16.37, 95% CI (2.28, 117.68); P = 0.006] and reduced creatinine clearance prior to initiation of TDF [OR 1.44 for every 5 mL/min reduction, 95% CI (1.09, 1.92); P = 0.012; OR 19.77 for pre-TDF CrCl lower than 83 mL/min, 95% CI (2.24, 174.67); P = 0.007] were significantly associated with FS. Of the 14 cases followed for resolution, 7 (50%) achieved at least partial resolution (defined as recovering CrCl >70% of pre-TDF values) although most participants had full normalization of proximal tubulopathy markers within two months of TDF discontinuation.ConclusionsFS, defined by specific CrCl decreases and markers of tubulopathy, is more likely in those who have received or are currently receiving concomitant lopinavir/ritonavir or who had lower CrCl prior to TDF initiation. Half of those with protocol-defined FS had CrCl recover to near pre-TDF values during the first year after TDF discontinuation.

Renal Impairment in Patients Receiving a Tenofovir-cART Regimen

Tenofovir disoproxil fumarate (TDF) is known to induce renal dysfunction in HIV-infected patients. The aim of this retrospective study was to evaluate the correlation between TDF trough concentration (Ctrough-TDF) and glomerular filtration rate (GFR) in a cohort of patients on antiretroviral therapy. A total of 163 patients with at least one determination of Ctrough-TDF between 17-24 hours were retrospectively selected from a computerized database and distributed into 3 groups defined by TDF concentrations <40 (11.7%), between 40 and 90 (36.8%), and >90 (high-level group, 51.5%) ng/mL. GFR was measured by Cockcroft-Gault, Modification of Diet in Renal Disease, and Chronic Kidney Disease Epidemiology Collaboration formulae at the times of TDF initiation and Ctrough-TDF determination and after 12 months. At the time of Ctrough-TDF measurement, median duration of TDF-based therapy was 21.1 months. GFR was significantly decreased in high-level group (-8.5 mL/min; P < 0.001) whatever the method used. GFR decline was significantly associated with an older age. Gender-stratified analysis showed that the early impact of Ctrough-TDF >90 ng/mL was significant in women only. After 12 months, the decrease in GFR in patients with high Ctrough-TDF was observed in both men and women (-8.27; P = 0.003). The high prevalence of elevated Ctrough-TDF and its correlation with an increased risk of renal impairment support the usefulness of therapeutic drug monitoring for TDF, particularly in women and older patients.