Correlation Between Tenofovir Drug Levels and the Renal Biomarkers RBP-4 and ß2M in the ION-4 Study Cohort

Evaluating new biomarkers for diabetic nephropathy: Role of α2-macroglobulin, podocalyxin, α-L-fucosidase, retinol-binding protein-4, and cystatin C

BACKGROUND

The intricate relationship between type 2 diabetes mellitus (T2DM) and diabetic nephropathy (DN) presents a challenge in understanding the significance of various biomarkers in diagnosis.

AIM

To elucidate the roles and diagnostic values of α2-macroglobulin (α2-MG), podocalyxin (PCX), α-L-fucosidase (AFU), retinol-binding protein-4 (RBP-4), and cystatin C (CysC) in DN.

METHODS

From December 2018 to December 2020, 203 T2DM patients were enrolled in the study. Of these, 115 were diagnosed with DN (115 patients), while the remaining 88 patients were classified as non-DN. The urinary levels of α2-MG, PCX, and AFU and the serum concentrations RBP-4 and CysC were measured in conjunction with other relevant clinical indicators to evaluate their potential correlations and diagnostic utility.

RESULTS

After adjustments for age and gender, significant positive correlations were observed between the biomarkers CysC, RBP-4, α2-MG/urinary creatinine (UCr), PCX/UCr, and AFU/UCr, and clinical indicators such as urinary albumin-to-creatinine ratio (UACR), serum creatinine, urea, 24-h total urine protein, and neutrophil-to-lymphocyte ratio (NLR). Conversely, these biomarkers exhibited negative correlations with the estimated glomerular filtration rate (P < 0.05). Receiver operating characteristic (ROC) curve analysis further demonstrated the diagnostic performance of these biomarkers, with UACR showcasing the highest area under the ROC curve (AUCROC) at 0.97.

CONCLUSION

This study underscores the diagnostic significance of α2-MG, PCX, and AFU in the development of DN. The biomarkers RBP-4, CysC, PCX, AFU, and α2-MG provide promising diagnostic insights, while UACR is the most potent diagnostic biomarker in assessing DN.

Real-world effectiveness of direct-acting antivirals in people living with human immunodeficiency virus and hepatitis C virus genotype 6 infections

BACKGROUND

Hepatitis C virus (HCV) genotype 6 (HCV-6) infection is prevalent predominantly in Southeast Asia, and the data on the virologic response of HCV-6 to direct-acting antivirals (DAAs) are sparse in people living with human immunodeficiency virus (HIV) (PLWH).

AIM

To assess the virologic response of HCV-6 to DAAs in PLWH.

METHODS

From September 2016 to July 2019, PLWH coinfected with HCV-6 initiating DAAs were included. Laboratory investigations were performed at baseline, the end of treatment, and 12 wk off-therapy.

RESULTS

Of the 349 PLWH included (mean age 48.9 years, 82.5% men), 80.5% comprised people who inject drugs, 18.1% men who have sex with men, and 1.4% heterosexuals. Coexistent hepatitis B virus infection was present in 12.3% of the included PLWH, liver cirrhosis 10.9%, hepatocellular carcinoma 0.9%, and previous HCV treatment experience 10.9%. The mean baseline plasma HCV RNA was 6.2 log₁₀ IU/mL. Treatment with glecaprevir/pibrentasvir was initiated in 51.9%, sofosbuvir/ledipasvir 41.5%, sofosbuvir/velpatasvir 6.3%, and sofosbuvir/daclatasvir 0.3%. At DAA initiation, antiretroviral therapy containing tenofovir alafenamide was given in 26.4%, tenofovir disoproxil fumarate 34.4%, non-tenofovir alafenamide/tenofovir disoproxil fumarate 39.3%, non-nucleoside reverse-transcriptase inhibitors 30.4%, protease inhibitors 4.0%, and integrase strand transfer inhibitors 66.8%; 94.8% of the included patients had CD4 counts ≥ 200 cells/mm³ and 96.0% had plasma HIV RNA < 50 copies/mL. Overall, 96.8% achieved undetectable plasma HCV RNA (< 30 IU/mL) at end of treatment; and 92.3% achieved sustained virologic response 12 wk off-therapy in the intention-to-treat analysis (93.5% in patients receiving sofosbuvir-based DAAs and 91.2% in those receiving glecaprevir/pibrentasvir).

CONCLUSION

Similar to the observation made in HIV-negative patients, sustained virologic response 12 wk off-therapy with DAAs is high in PLWH coinfected with HCV-6.

Altering retinol binding protein 4 levels in hepatitis C: Inflammation and steatosis matter

Both hepatitis C virus (HCV) infection and retinol-binding protein 4 (RBP4) might contribute to insulin resistance (IR), how RBP4 links to IR in HCV infection remain elusive. A joint study of a prospective cohort of 842 chronically HCV-infected (CHC) patients (with 842 controls) and a line of HCV core transgenic mice was conducted. Of 842 patients, 771 had completed anti-HCV therapy and 667 had sustained virological responses (SVRs). Compared with controls, CHC patients had lower RBP4 levels. At baseline, age (95% CI β: -0.87~-0.317), BMI (0.516~2.036), triglycerides (0.03~0.127), neutrophil-to-lymphocyte ratio (NLR) (1.561~7.327), and estimated glomerular filtration rate (eGFR) (-0.342~-0.149) levels were associated with RBP4 levels in CHC patients. At 24-week post-therapy, male sex (0.652~8.129), BMI (0.199~1.254), triglycerides (0.039~0.088), uric acid (0.599~3.067), eGFR (-0.247 ~-0.14) levels, and fibrosis-4 (-3.602~-0.039) scores were associated with RBP4 levels in SVR patients; compared with baseline, except genotype 3 HCV-infected patients, SVR patients had increased RBP4 levels, which were comparable with controls, while no HOMA-IR index alteration was noted after SVR. The HCV core transgenic mice exhibited nonobese hepatic steatosis, had higher hepatic RBP4 expression, higher serum levels of RBP4 and triglycerides, but comparable HOMA-IR levels than non-transgenic littermates. In conclusion, steatosis, sex, age, uric acid, NLR, and FIB-4 levels were associated with HCV-related RBP4 levels; BMI, triglycerides, and eGFR levels were associated with non-HCV-related RBP4 levels. Reversal of low RBP4 levels after SVR was evident in non-genotype 3 HCV-infected patients. Steatosis and inflammation linked with metabolic alteration other than IR, determined RBP4 levels in HCV-infected patients.

Pharmacokinetics and renal safety of tenofovir alafenamide with boosted protease inhibitors and ledipasvir/sofosbuvir

BACKGROUND

Ledipasvir/sofosbuvir increases tenofovir plasma exposures by up to 98% with tenofovir disoproxil fumarate (TDF), and exposures are highest with boosted PIs. There are currently no data on the combined use of the newer tenofovir prodrug, tenofovir alafenamide (TAF), boosted PIs and ledipasvir/sofosbuvir.

OBJECTIVES

To compare the plasma and intracellular pharmacokinetics and renal safety of TAF with ledipasvir/sofosbuvir when co-administered with boosted PIs.

METHODS

Persons with HIV between 18 and 70 years and on a boosted PI with TDF were eligible. The study was comprised of four phases: (1) TDF 300 mg with boosted PI; (2) TAF 25 mg with boosted PI; (3) TAF 25 mg with boosted PI and ledipasvir/sofosbuvir; and (4) TAF 25 mg with boosted PI. Pharmacokinetic sampling, urine biomarker collection [urine protein (UPCR), retinol binding protein (RBP) and β2 microglobulin (β2M) normalized to creatinine] and safety assessments occurred at the end of each phase. Plasma, PBMCs and dried blood spots were collected at each visit.

RESULTS

Ten participants were enrolled. Plasma tenofovir exposures were 76% lower and tenofovir-diphosphate (TFV-DP) concentrations in PBMCs increased 9.9-fold following the switch to TAF. Neither of these measures significantly increased with ledipasvir/sofosbuvir co-administration, nor did TAF plasma concentrations. No significant changes in estimated glomerular filtration rate or UPCR occurred, but RBP:creatinine and β2M:creatinine improved following the switch to TAF.

CONCLUSIONS

Ledipasvir/sofosbuvir did not significantly increase plasma tenofovir or intracellular TFV-DP in PBMCs with TAF. These findings provide reassurance that the combination of TAF, boosted PIs and ledipasvir/sofosbuvir is safe in HIV/HCV-coinfected populations.

Evolution of estimated glomerular filtration rate in human immunodeficiency virus and hepatitis C virus-coinfected patients receiving sofosbuvir-based direct-acting antivirals and antiretroviral therapy

The nephrotoxicity of sofosbuvir (SOF) on human immunodeficiency virus and hepatitis C virus (HIV/HCV)-coinfected patients receiving antiretroviral therapy (ART) remains controversial. We prospectively compared the estimated glomerular filtration rate (eGFR) changes in 167 patients receiving SOF-based direct-acting antivirals (DAAs) who also received tenofovir disoproxil fumarate (TFV)-based (n = 116) and TFV-free ART (n = 51). The eGFR was assessed by the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation, and the eGFR changes between ART regimens were compared by the generalized estimated equation. During DAA treatment, participants on TFV-based ART had a higher eGFR decline than those on TFV-free ART (slope coefficient difference: -0.82 ml/min/1.73 m² /month [95% CI: -1.21 to -0.43]; p < 0.001), whereas the eGFR changes did not differ between groups (slope coefficient difference: 0.13 ml/min/1.73 m² /month [95% CI: -0.32 to 0.58]; p = 0.42) after discontinuing DAAs. Participants on TFV TDF-based ART had a higher eGFR decline than those on TFV alafenamide fumarate (TAF)-based ART (slope coefficient difference: -0.31 ml/min/1.73 m² /month [95% CI: -0.50 to -0.12]; p = 0.01). After discontinuing DAAs, the eGFR changes did not differ between groups (slope coefficient difference: 0.06 ml/min/1.73 m² /month [95% CI: -0.98 to 1.10]; p = 0.91). In conclusion, HIV/HCV-coinfected patients on TFV-based ART had a slight eGFR decline compared to those on TFV-free ART during SOF-based DAA therapy. A similar trend between TDF-based and TAF-based ART was also observed. Because the differences of eGFR changes are limited, the physicians should not discourage the use of SOF-based DAAs in HIV-positive patients on TFV-based ART.

PrEParing for Preexposure Prophylaxis

BACKGROUND

In 2012 the Food and Drug Administration (FDA) approved Truvada (emtricitabine [FTC] 200 mg/tenofovir disoproxil fumarate [TDF] 300 mg) for preexposure prophylaxis (PrEP) against HIV. There was a substantial decline in new HIV diagnoses which has since stabilized.

OBJECTIVE

The plateau is thought to be because preventative efforts are not reaching high-risk groups. About 1.2 million adults in the United States could benefit from PrEP but only 80,000 individuals are taking it. This article aims to increase provider awareness of PrEP so primary care providers feel confident discussing risk reduction options, initiating, and monitoring PrEP.

METHODS

A case based approached is used to achieve the objective.

RESULTS

Target populations, baseline labs, follow up labs and monitoring parameters, and side effects of medication will be reviewed. Patient counseling with regards to dosing, administration, side effects and adverse events will be discussed.

CONCLUSIONS

HIV prevention is an integral public health goal. PrEP is a way to achiveeve continued reduction in HIV incidence. PCPs should be offering PrEP to at risk individuals.

IMPLICATIONS FOR NURSING

Many nurse practitioners work as primary care providers, this article hopes to increase the confidence of PCPs in prescribing PrEP to those who would benefit from it.

Safety, efficacy, and pharmacokinetics of pradefovir for the treatment of chronic hepatitis B infection

BACKGROUND & AIMS

Pradefovir is a liver targeted novel prodrug of adefovir (PMEA) developed to provide higher antiviral activity with reduced systemic toxicities. This study evaluated the tolerability, pharmacokinetics, and antiviral activity of pradefovir in patients with chronic hepatitis B (CHB) virus infection.

METHODS

Non-cirrhotic, treatment-naïve subjects with CHB were divided into five groups (10 patients each) and randomized within each group in a ratio of 6:2:2 to receive an ascending dose of 30, 60, 75, 90, or 120 mg pradefovir, 10 mg adefovir dipivoxil (ADV), or 300 mg tenofovir disoproxil fumarate (TDF) once a day for 28 days.

RESULTS

A total of 51 subjects were randomized and 49 subjects completed the study. The groups were well matched and included 39 males, of whom 71% were hepatitis B e-antigen-negative with a mean hepatitis B virus (HBV) DNA level of 6.4-7.16 log10 IU/mL. No subject experienced a serious adverse event or nephrotoxicity. The most frequently reported adverse event was asymptomatic reduction in blood cholinesterase levels in the pradefovir group which recovered without any treatment about 13 ± 7 days after drug discontinuation. This adverse event was not observed in the ADV and TDF groups. The mean changes in serum HBV DNA were -2.78, -2.77, -3.08, -3.18, -3.44, -2.34, and -3.07 log10 IU/mL at 30, 60, 75, 90, and 120 mg pradefovir, 10 mg ADV and 300 mg TDF, respectively, with plateau levels reached with 60 mg pradefovir. Pradefovir and its metabolite PMEA showed linear pharmacokinetics proportional to the dose. The half-life of PMEA in the pradefovir group was 11.47-17.63 h.

CONCLUSIONS

Short-term use of pradefovir was well tolerated. A decline in HBV DNA levels was superior to TDF at higher doses of pradefovir. 30-60 mg pradefovir is recommended for CHB treatment.

CLINICAL TRIAL NUMBER

CTR20150224.