Renal health after long-term exposure to tenofovir disoproxil fumarate (TDF) in HIV/HBV positive adults in Ghana

Association of tenofovir diphosphate and lamivudine triphosphate concentrations with HIV and hepatitis B virus viral suppression

OBJECTIVE

Concentrations of tenofovir diphosphate (TFV-DP) and lamivudine triphosphate (3TC-TP) in cells are correlates of medication adherence and antiviral activity. However, studies have yet to characterize the simultaneous relationship between TFV-DP and 3TC-TP concentrations with HIV and hepatitis B virus (HBV) suppression.

METHODS

Individuals with HIV/HBV coinfection on tenofovir disoproxil fumarate (TDF)-containing antiretroviral therapy (ART) were enrolled. Peripheral blood mononuclear cells (PBMCs) and dried blood spots (DBS) samples were collected and steady-state TFV-DP and 3TC-TP concentrations quantified using validated methods. The relationship between patient factors, TFV-DP, and 3TC-TP concentrations in PBMCs and DBS with HBV and HIV viral suppression were examined.

RESULTS

Of 138 participants on TDF-containing ART for a median duration (range) of 6 (0.75-15) years, the median age was 43 years and 64% were women. Overall, 128 (92.8%) and 129 (93.5%) had suppressed HIV and HBV viral loads, respectively. Of the 128 participants with suppressed HIV, 122 (95.3%) had suppressed HBV. Self-reported ART adherence, recent change to dolutegravir-based ART, TFV-DP, and 3TC-TP concentrations in PBMCs and DBS were associated with HIV RNA suppression, while HBe antigen positivity, HIV suppression, and TFV-DP concentrations in DBS were associated with HBV DNA suppression (including six persons with HBV nonsuppression and HIV suppression).

CONCLUSION

Long-term TDF/3TC-conatining ART was highly efficacious in individuals with HIV/HBV coinfection. Higher TFV-DP concentrations were predictive of suppression for both viruses. Persistent HBV viremia on TDF/3TC-containg ART requires additional research, but may represent poor adherence and the need for adherence interventions or novel antivirals.

Health inequalities in the management of chronic hepatitis B virus infection in patients from sub-Saharan Africa in high-income countries

Chronic hepatitis B virus disproportionately affects migrant communities in high-income countries, reflecting increased migration from sub-Saharan Africa. Chronic hepatitis B virus is endemic in sub-Saharan Africa, yet the natural history of chronic infection experienced by patients remains incompletely understood, with evidence of variability across genotypes and regions within sub-Saharan Africa. Clinical guidelines recommending treatment thresholds are not specific to sub-Saharan African patients and are based on natural history studies from Western Pacific Asian countries. Access to standard of care treatment is available for sub-Saharan African people with chronic hepatitis B virus infection in high-income countries; however, the evidence base for these treatments was not established in this cohort and areas of uncertainty remain, particularly regarding HCC surveillance and treatment discontinuation. Participation in phase III clinical trials for chronic hepatitis B therapies is almost non-existent amongst sub-Saharan African patients, even when residing in high-income countries that participate in multicentre trials. Engagement with sub-Saharan African patients with chronic hepatitis B in high-income countries is challenging because of the stigma associated with the diagnosis, absence of routine screening systems and the complexities involved in navigating the healthcare system. Nonetheless, improved engagement is critical if we are to achieve global hepatitis B virus elimination.

Hepatitis B virus (HBV) viral load, liver and renal function in adults treated with tenofovir disoproxil fumarate (TDF) vs. untreated: a retrospective longitudinal UK cohort study

BACKGROUND

Current clinical guidelines recommend treating chronic hepatitis B virus (HBV) infection in a minority of cases, but there are relatively scarce data on evolution or progression of liver inflammation and fibrosis in cases of chronic HBV (CHB) that do not meet treatment criteria. We aimed to assess the impact of TDF on liver disease, and the risk of renal impairment in treated CHB patients in comparison to untreated patients.

METHODS

We studied a longitudinal ethnically diverse CHB cohort in the UK attending out-patient clinics between 2005 and 2018. We examined TDF treatment (vs. untreated) as the main exposure, with HBV DNA viral load (VL), ALT, elastography scores and eGFR as the main outcomes, using paired tests and mixed effects model for longitudinal measurements. Additionally, decline of eGFR during follow-up was quantified within individuals by thresholds based on clinical guidelines. Baseline was defined as treatment initiation for TDF group and the beginning of clinical follow-up for untreated group respectively.

RESULTS

We included 206 adults (60 on TDF, 146 untreated), with a median ± IQR follow-up duration of 3.3 ± 2.8 years. The TDF group was significantly older (median age 39 vs. 35 years, p = 0.004) and more likely to be male (63% vs. 47%, p = 0.04) compared to the untreated group. Baseline difference between TDF and untreated groups reflected treatment eligibility criteria. As expected, VL and ALT declined significantly over time in TDF-treated patients. Elastography scores normalised during treatment in the TDF group reflecting regression of inflammation and/or fibrosis. However, 6/81 (7.4%) of untreated patients had a progression of fibrosis stage from F0-F1 to F2 or F3. There was no evidence of difference in rates or incidence of renal impairment during follow-up in the TDF vs. untreated group.

CONCLUSIONS

Risk of liver inflammation and fibrosis may be raised in untreated patients compared to those receiving TDF, and TDF may benefit a larger percentage of the CHB population.

Calcaneal Quantitative Ultrasonography and Urinary Retinol-Binding Protein in Antiretroviral-Treated Patients With Human Immunodeficiency Virus in Uganda: A Pilot Study

BACKGROUND

Data on bone health and renal impairment in people with human immunodeficiency virus (HIV) in resource-limited settings are limited. The primary aim of this study was to investigate the potential role of calcaneal quantitative ultrasonography (QUS) in predicting bone mineral density (BMD) reduction in a population of Ugandan HIV-infected  individuals receiving long-term antiretroviral therapy; the secondary end point was to assess the prevalence of proximal tubular dysfunction and the correlation between elevated urinary retinol-binding protein-urinary creatinine ratio (uRBP/uCr) and reduced BMD.

METHODS

We conducted a cross-sectional study at the Infectious Diseases Institute, Kampala, Uganda. We included 101 HIV-infected adults who had been receiving continuous antiretroviral therapy for ≥10 years and had undergone dual-energy x-ray absorptiometry (DXA) during the previous 12 months. All patients underwent calcaneal QUS evaluation and urine sample collection.

RESULTS

DXA BMD measurements were significantly associated (P < .01) with calcaneal speed of sound, broadband ultrasound attenuation, and QUS index. Forty-seven individuals (47%) had abnormal uRBP/uCr values. A significant inverse correlation was observed between uRBP/uCr and DXA T scores (lumbar [P = .03], femoral neck [P < .001], and total hip [P = .002]).

CONCLUSIONS

Calcaneal QUS results showed a moderate correlation with DXA outputs. The identified high prevalence of subclinical tubular impairment also highlights the importance of expanding access to tenofovir disoproxil fumarate-sparing regimens in resource-limited settings.

Duration of antiretroviral therapy among people living with HIV and incidence of hypertension in Ghana

Understanding the differential rates of incident hypertension among People Living with HIV (PLWH) based of duration of exposure to combination antiretroviral therapy (cART) may provide insights into the pathogenesis of hypertension in this population. Utilizing the dataset of a prospective study conducted at a Ghanaian tertiary medical center, we evaluated factors associated with incident hypertension among PLWH previously naïve to cART before study enrollment (cART newly prescribed group, n = 221) versus PLWH established on cART for at least a year (cART established group, n = 212). New-onset hypertension was diagnosed as clinic BP > 140/90 mmHg on two separate clinic visits over 12-month follow-up. Cox proportional hazards regression models were used to assess factors associated with incident hypertension. Mean age of new versus cART established was 41.1 ± 8.2 versus 45.1 ± 8.6 years (p < .001), with more women in the cART established group (68.3 vs. 82%, p = .0009). There were 105 (24.3%) episodes of incident hypertension over 328 person-years follow-up (PYFU), incidence rate of 320.1 (95% CI: 263.1-385.9)/1000 PYFU, with higher rates in new versus cART established (476.6/1000 PYFU vs. 222.8/1000 PYFU, p = 0.0002). Overall, age by increasing decile (aHR 0.76; 95% CI: 0.59-0.98), log HIV-1 viral load (aHR 1.16; 1.04-1.35), and use of tenofovir (aHR 1.66; 1.04-2.64) were associated with incident hypertension. While CD4 counts, age, BMI, pre-diabetes, and urban/peri-urban residency were independently associated with hypertension in the cART established group; no independent predictors were identified among the cART newly prescribed group. Further studies to explore the potential mechanisms underlying incidence of hypertension in PLWH are warranted.

Longer-term effectiveness of protease-inhibitor-based second line antiretroviral therapy in four large sub-Saharan African clinics

OBJECTIVES

Data on the longer-term effectiveness of second line combination antiretroviral therapy (ART) in sub-Saharan Africa (SSA) are lacking. We sought to assess the probability and determinants of 2nd line ART failure in SSA.

METHODS

A retrospective, multi-center study of 2nd line ART initiated between 2005 and 2017 at four ART centers in Ethiopia, Ghana and Uganda. Main outcome measure was virologic failure (VF) defined as VL>1000 copies/ml after >6 months on 2nd line therapy. Predictors of VF and virologic re-suppression on 2nd line were evaluated using Cox Proportional Hazards and multivariable logistic regression models, respectively.

RESULTS

2191 subjects started 2nd line therapy, 61.5% females. Switching from 1st line (56.4% NVP-based, 70.3% including thymidine-analogues) to 2nd line therapy occurred after mean of 4.1 years. 98.9% of patients started boosted PI with NRTI backbone (TDF+3TC/FTC 67.3%, AZT+3TC 18.5%, others 14.2%). There were 267 (12.0%) VF with a 5-year estimated probability of 15.0% (95% CI 13.2-16.9). Key determinants of VF were concomitant rifampicin use (aHR 2.50 [95% CI 1.54-4.05]) and clinical/immunological failure versus virologic failure as reason for switching therapy (aHR, 0.53 [0.33-0.86]). 138 of 267 (51.7%) subsequently achieved virologic re-suppression and predictors included HIV RNA levels at 2nd-line failure: +1 log higher aOR 0.59 [0.43-0.80], experiencing change within 2nd line ART before VF: aOR 0.17 [0.05-0.56], and more recent calendar year of 2nd line initiation: aOR 0.85 [0.75-0.94].

CONCLUSIONS

The effectiveness of current 2nd line ART regimens in SSA is good but challenged by interactions with TB therapy.