Fanconi Syndrome in Patients With Human Immunodeficiency Virus Treated With Tenofovir-Based Antiretroviral Therapy: A Systematic Literature Review

OBJECTIVE

Several cases of Fanconi syndrome (FS), a severe form of nephrotoxicity, have been reported in patients with HIV on tenofovir-containing antiretroviral therapy. A systematic review of the published literature on tenofovir-related FS in patients with HIV was conducted.

DATA SOURCES

PubMed and Embase were queried to identify articles in English published between January 2005 and June 2023, reporting tenofovir-related FS in adults with HIV. Preclinical studies, conference/poster abstracts, commentaries and responses, and review papers were excluded.

STUDY SELECTION AND DATA EXTRACTION

Of the 256 articles screened, 57 met the inclusion criteria. These comprised 37 case reports, 11 case series, 1 cross-sectional study, 1 case-control study, 4 cohort studies, 1 single-arm open-label clinical trial, 1 sub-analysis of clinical trials, and 1 pooled analysis of clinical trials.

DATA SYNTHESIS

Among 56 cases on which information was abstracted, median age at FS diagnosis was 50 years, 51.8% were men, and duration of tenofovir use ranged from 6 weeks to 11 years. Ritonavir was co-prescribed in almost half the cases. In observational and interventional studies, incidence of FS was low. Many studies reported resolution of FS symptoms after tenofovir discontinuation. All FS occurrences were identified in those on tenofovir disoproxil fumarate (TDF), except for one patient on tenofovir alafenamide (TAF).

RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE

Continuous monitoring of signs and symptoms of renal and bone toxicity is essential for patients with HIV on tenofovir-containing therapy.

CONCLUSIONS

Occurrence of FS is low in patients with HIV treated with tenofovir-based regimens. Concomitant use of ritonavir may increase risk of FS. TAF may be a safer alternative than TDF in terms of nephrotoxicity.

Real-World Single-Center Comparison of the Safety and Efficacy of Entecavir, Tenofovir Disoproxil Fumarate, and Tenofovir Alafenamide in Patients with Chronic Hepatitis B

INTRODUCTION

Chronic hepatitis B (CHB) is a major cause of chronic liver diseases and tenofovir disoproxil fumarate (TDF), tenofovir alafenamide (TAF), and entecavir (ETV) are recommended as primary treatments. This study aimed to evaluate the efficacy and safety of ETV, TDF, and TAF in a real-world clinical setting.

METHODS

In this retrospective cohort study, a total of 363 CHB patients who were treated with ETV (n = 163), TDF (n = 154), or TAF (n = 46) from July 2007 to September 2019 were enrolled.

RESULTS

Median patient age was 51 years and 66.4% of patients were male. Median duration of treatment with ETV, TDF, or TAF was 49.0 months (interquartile range, 27.0-74.0 months). In terms of safety, cholesterol was mildly increased in the ETV and TAF groups and significantly lowered in the TDF group than baseline (p < 0.001). There was no significant difference in liver cirrhosis-related complications among the 3 groups at 48 weeks (p = 0.235). Hepatitis B e antigen seroconversion, complete virological response, and alanine aminotransferase normalization at 48 weeks as measures of treatment efficacy were not significantly different among the 3 groups (p = 0.142, 0.538, and 0.520, respectively). There was also no significant difference in cumulative incidence rate of hepatocellular carcinoma (HCC) between the ETV and TDF groups (p = 0.894).

CONCLUSIONS

ETV, TDF, and TAF were safe antiviral agents and showed similar antiviral effect for CHB at 48 weeks. Cirrhosis-related complications and annual HCC incidence rates did not differ significantly between the ETV and TDF groups over the 48 week follow-up period.

Bone Age and Mineral Density Assessments Using Plain Roentgenograms in Tenofovir-exposed Infants in Malawi and Brazil Enrolled in HIV Prevention Trials Network 057

BACKGROUND

Tenofovir disoproxil fumarate (TDF) use during pregnancy has been increasing, and studies linking bone toxicity with exposure to TDF have raised concern for its use in infants.

METHODS

Hand/wrist and spine radiographs were obtained at 3 days and 12 weeks of age in infants born to HIV-infected pregnant women enrolled in the HIV Prevention Trials Network 057 pharmacokinetic study of TDF conducted in Malawi and Brazil assigned to 3 TDF dosing cohorts. In cohort 1, mothers received 600 mg of TDF during labor. In cohort 2, infants received 4 mg/kg dose on days 0, 3 and 5. In cohort 3, a 900 mg maternal dose was given during labor, followed by a 6 mg/kg infant dose on days 0, 3 and 5 of life.

RESULTS

Across all 3 cohorts, 89 infants had radiographs performed at either time point, and 85 had radiographs performed at both time points. Metaphyseal lucency was present in 1 case in Brazil and 2 in Malawi. Fifteen percent of infants from Brazil and 9% of infants from Malawi presented bone age discrepancies. No other abnormalities were identified in Brazil, whereas in Malawi, there were 7 more cases of wrist osteopenia, 2 of spine osteopenia and 3 other abnormalities.

CONCLUSION

Bone abnormalities were not uncommon in the overall cohort of HIV-exposed infants. Because of very limited study drug exposure at the time of birth, it is unlikely that TDF was associated with these findings. Untreated maternal HIV disease and/or maternal nutritional status could potentially be related to fetal bone development. This association should be explored in future cohort studies.

Elevation in Serum Concentration of Bone-Specific Alkaline Phosphatase without Elevation in Serum Creatinine Concentration Secondary to Adefovir Dipivoxil Therapy in Chronic Hepatitis B Virus Infection

Of 168 patients with chronic hepatitis B virus (HBV) infection-related liver disease, 20 patients who had received 100 mg of lamivudine plus 10 mg/day of adefovir dipivoxil (ADV) (ADV group) and 124 patients who had received 0.5 mg/day of entecavir or 100 mg/day of lamivudine (non-ADV group) for >1 year were enrolled. For comparative analyses, 19 well-matched pairs were obtained from the groups by propensity scores. At the time of enrollment, serum creatinine and phosphate concentrations were similar between the ADV and non-ADV groups; however, urinary phosphate (P = 0.0424) and serum bone-specific alkaline phosphatase (BAP) (P = 0.0228) concentrations were significantly higher in the ADV group than in the non-ADV group. Serum BAP was significantly higher at the time of enrollment than before ADV administration in the ADV group (P = 0.0001), although there was no significant change in serum BAP concentration in the non-ADV group. There was a significant positive correlation between the period of ADV therapy and ΔBAP (R (2) = 0.2959, P = 0.0160). Serum BAP concentration increased before increase in serum creatinine concentration and was useful for early detection of adverse events and for developing adequate measures for continuing ADV for chronic HBV infection-related liver disease.

Endocrine and metabolic abnormalities among HIV-infected patients: A current review

Multiple endocrine and metabolic abnormalities have been reported among human immunodeficiency virus (HIV) patients since the pre-antiretroviral therapy era. These abnormalities present with either subclinical or overt clinical features. Endocrine and metabolic abnormalities primarily occur due to the direct destructive effects of HIV, malignancies and opportunistic infections on the varied endocrine glands and antiretroviral therapy-associated toxicities. This article offers a broad review on the commonly encountered endocrine and metabolic abnormalities among HIV-infected patients. Timely endocrine or metabolic evaluations should be performed among patients suspected with endocrine or metabolic dysfunction and appropriate treatment instituted since the majority of these conditions pose an increased risk of mortality if undiagnosed or untreated.

Antiretroviral therapy in Indian setting: when & what to start with, when & what to switch to?

With the rapid scale up of antiretroviral therapy, there is a dramatic decline in HIV related morbidity and mortality in both developed and developing countries. Several new safe antiretroviral, and newer class of drugs and monitoring assays are developed recently. As a result the treatment guideline for the management of HIV disease continue to change. This review focuses on evolving science on Indian policy - antiretroviral therapy initiation, which drugs to start with, when to change the initial regimen and what to change.

Hypophosphatemic Osteomalacia Associated with Tenofovir: a Multidisciplinary Approach is Required

Tenofovir is widely used as first-line treatment of HIV infection, although its use is sometimes complicated by a reversible proximal renal tubulopathy.We report the case of a 45-year-old woman with chronic HIV infection and personality disorder, who after 12 months of tenofovir, complained of fatigue, diffuse bone pain and gait disturbances. The elevated level of alkaline phosphatase, hypophosphatemia and inappropriate phosphaturia suggested the diagnosis of hypophosphatemic osteomalacia secondary to proximal renal tubulopathy. A dual-energy x-ray absorptiometry showed a bone mineral density below the expected range for age (lumbar spine Z-score -3.3, femoral neck Z-score -2.1). A whole body (99m)Tc-methylene diphosphonate bone scan showed multiple areas of increased focal activity in the lumbar and thoracic spine and in sacroiliac and hip joints consistent with pseudofractures. Two months after tenofovir discontinuation and administration of vitamin D and phosphate, osteomalacia-related symptoms disappeared. Eleven months later, bone and mineral metabolism data were normal and bone scintigraphy did not show any pathological findings.This report highlights the importance of considering the diagnosis of osteomalacia in patients treated with tenofovir and emphasizes the need for monitoring alkaline phosphatase, blood and urinary phosphate and creatinine, especially in patients with risk factors for bone disease.