Association between HBs Ag quantification and the risk of hepatocellular carcinoma in patients treated with tenofovir disoproxil fumarate or entecavir

This study evaluated the clinical implications of hepatitis B surface antigen quantification (qHBs Ag) in chronic hepatitis B (CHB) patients treated with entecavir (ETV) or tenofovir disoproxil fumarate (TDF) and identified the association between qHBs Ag and the risk of hepatocellular carcinoma (HCC) in these patients.Between January 2007 and December 2018, the qHBs Ag and clinical data of 183 CHB patients who initially received ETV (n = 45, 24.6%) or TDF (n = 138, 75.4%) were analyzed.The mean follow-up period of the 183 CHB patients was 45.3 months, of which 59 (32.2%) patients showed a reduction in qHBs Ag by >50% after 1 year of antiviral treatment (ETV or TDF). The HCC development (P = .179) or qHBs Ag reduction (P = .524) were similar in the ETV and TDF groups. Patients with a ≥50% decrease in qHBs Ag had a significantly lower incidence of HCC or decompensated cirrhosis complications (P = .005). Multivariate analysis showed that a >50% reduction of qHBs Ag (hazard ratio 0.085, P = .018) and the presence of cirrhosis (hazard ratio 3.32, P = .016) were independent factors predicting the development of HCC.Patients whose qHBs Ag value decreased >50% at 1 year after antiviral treatment for CHB showed a significant decrease in HCC or decompensated cirrhosis events. A reduction in qHBs Ag could be used as a predictive factor of HCC development or critical complications in CHB patients treated with TDF or ETV.     

Validation of risk prediction scores for hepatocellular carcinoma in patients with chronic hepatitis B treated with entecavir or tenofovir

Several prediction scores for the early detection of hepatocellular carcinoma (HCC) are available. We validated the predictive accuracy of age, albumin, sex, liver cirrhosis (AASL), RESCUE‐B, PAGE‐B and modified PAGE‐B (mPAGE‐B) scores in chronic hepatitis B (CHB) patients treated with entecavir (ETV) or tenofovir disoproxil fumarate (TDF). Between 2007 and 2014, 3171 patients were recruited (1645, ETV; 1517, TDF). The predictive accuracy of each prediction score was assessed. The mean age of the study population (1977 men; 1194 women) was 48.8 years. Liver cirrhosis was present in 1040 (32.8%) patients. During follow‐up (median, 58.2 months), 280 (8.8%) patients developed HCC; these patients were significantly older; more likely to be male; had significantly higher proportions of liver cirrhosis, hypertension and diabetes; and had significantly higher values for the four risk scores than those who did not develop HCC (all P < .05). Older age (hazard ratio [HR] = 1.048), male sex (HR = 2.142), liver cirrhosis (HR = 3.144) and prolonged prothrombin time (HR = 2.589) were independently associated with an increased risk of HCC (all P < .05), whereas a higher platelet count (HR = 0.996) was independently associated with a decreased risk of HCC (P < .05). The predictive accuracy of AASL score was the highest for 3‐ and 5‐year HCC predictions (areas under the curve [AUCs] = 0.818 and 0.816, respectively), followed by RESCUE‐B, PAGE‐B and mPAGE‐B scores (AUC = 0.780‐0.815 and 0.769‐0.814, respectively). In conclusion, four HCC prediction scores were assessed in Korean CHB patients treated with ETV or TDF. The AASL score showed the highest predictive accuracy.     

替诺福韦酯治疗慢性乙型肝炎的最新进展

在众多核苷和核苷酸类药物（NAs）中,替诺福韦（TDF）以其强效、低耐药性及对多种 NAs治疗失败的慢性乙型肝炎（CHB）患者有效的特点脱颖而出,使其在临床HBV感染治疗中被广泛应用。介绍了TDF对CHB初治患者和经治患者的疗效,并分析了其对肝硬化患者治疗的效果,同时也对TDF治疗的安全性进行了评估。认为TDF耐药率低、安全性好,为目前CHB治疗的一线药物。     

No detectable resistance to tenofovir disoproxil fumarate in HBeAg+ and HBeAg− patients with chronic hepatitis B after 8 years of treatment

A major hurdle in the long‐term treatment of chronic hepatitis B (CHB) patients is to maintain viral suppression in the absence of drug resistance. To date, no evidence of resistance to tenofovir disoproxil fumarate (TDF) has been observed. A cumulative evaluation of CHB patients who qualified for resistance surveillance over 8 years of TDF treatment was conducted. Patients in studies GS‐US‐174‐0102 (HBeAg?) and GS‐US‐174‐0103 (HBeAg+) were randomized 2:1 to receive TDF or adefovir dipivoxil (ADV) for 48 weeks followed by open‐label TDF through year 8. Population sequencing of HBV pol/RT was attempted for all TDF‐treated patients at baseline and, annually if viremic, at discontinuation, or with addition of emtricitabine. Overall, 88/641 (13.7%) patients qualified for sequence analysis at one or more time points. The percentage of patients qualifying for sequence analysis declined over time, from 9 to 11% in years 1‐2 to <4% over years 3‐8. Forty‐one episodes of virologic breakthrough (VB) occurred throughout the study, with most (n=29, 70%) associated with nonadherence to study medication. Fifty‐nine per cent of VB patients with an opportunity to resuppress HBV achieved HBV DNA resuppression. A minority of patients who qualified for sequencing had polymorphic (41/165, 24.8%) or conserved (17/165, 10.3%) site changes in pol/RT, with six patients developing lamivudine and/or ADV resistance‐associated mutations. No accumulation of conserved site changes was detected. The long‐term treatment of CHB with TDF monotherapy maintains effective suppression of HBV DNA through 8 years, with no evidence of TDF resistance or accumulation of conserved site changes.     

Long‐term entecavir therapy results in falls in serum hepatitis B surface antigen levels and seroclearance in nucleos(t)ide‐naïve chronic hepatitis B patients

Entecavir (ETV) is reported to result in suppression of hepatitis B virus DNA (HBV DNA) replication with minimal drug resistance. However, information on the long‐term effect of such therapy on serum hepatitis B surface antigen (HBsAg) level and elimination of HBsAg is not available. ETV therapy was started in 553 nucleos(t)ide‐naïve patients with chronic hepatitis B infection (HBeAg positive: 45%) in our hospital. Serum HBsAg levels were measured serially by the Architect assay. The median baseline HBsAg was 2180 IU/mL (0.12–243 000 IU/mL), and median follow‐up period was 3.0 years, with 529, 475, 355, 247 and 163 patients followed‐up for 1, 2, 3, 4 and 5 years, respectively. At year 5, the mean log HBsAg decline from baseline was −0.48 log IU/mL, and the cumulative HBsAg clearance rate was 3.5%. Multivariate analysis identified HBV DNA level at baseline (<3.0 log copies IU/mL, odd ratio = 10.2; 95% confidence interval = 1.87–55.5, P = 0.007) and HBsAg level (<500 IU/mL, odd ratio = 29.4; 95% confidence interval = 2.80–333, P = 0.005) as independent predictors of HBsAg seroclearance. These results indicate that although serum HBsAg level declines gradually during ETV therapy, HBsAg seroclearance remains a rare event.     

Maintained virological suppression and renal function with reduced dose tenofovir disoproxil fumarate in renally impaired chronic hepatitis B patients

Tenofovir disoproxil fumarate (TDF) effectively suppresses viral replication in chronic hepatitis B (CHB), but occasionally leads to renal impairment. We evaluated the prevalence of viral and biochemical breakthrough and renal function kinetics in renally impaired patients with CHB on reduced and on full‐dose TDF. This clinic‐based longitudinal cohort study included patients receiving full and reduced dose TDF (due to eGFR [Cockcroft‐Gault] <60 mL/min/1.73 m²). Viral and biochemical breakthroughs were assessed 1 month after starting full and reduced TDF dose until the end‐of‐follow‐up. Breakthroughs were studied in full and reduced dose TDF, and renal function (MDRD) longitudinally before and after dose reduction within patients starting on full‐dose TDF. Of 750 patients on TDF, 78 (10%) had reduced dose and 672 (90%) full dose. At the time of dose reduction, 36 (46%) patients had chronic kidney disease stage G3B. A viral breakthrough occurred in one cirrhotic dialysis‐dependent patient (dosed 300 mg weekly) which resolved without signs of decompensation, and in one patient on full dose which resolved spontaneously. One biochemical breakthrough occurred during dose reduction and resolved naturally without viral breakthrough. The MDRD improved within the first year of dose reduction (+3.0 [2.5] mL/min per year; P < .005) and remained stable thereafter. Fifty‐three (79%) patients reached an MDRD >50 mL/min during dose reduction. Low dose TDF maintains renal function and viral suppression in most renally impaired patients with CHB, even in those with advanced liver disease. This useful, yet simple strategy could be particularly viable in resource‐constrained settings.     

替诺福韦酯对阿德福韦酯应答不佳患者的挽救治疗研究进展

阿德福韦酯(adefovir dipivoxil,ADV)作为常用抗HBV治疗药物,与拉米夫定(lamivudine,LAM)、替比夫定和恩替卡韦无交叉耐药,且价格相对低廉,长期以来用于初治患者和LAM耐药患者的挽救治疗。然而由于ADV耐药基因屏障较低且临床用药剂量较低,临床长期应用累积了较多ADV应答不佳患者。替诺福韦酯(tenofovir disoproxil fumarate,TDF)作为ADV应答不佳患者的挽救治疗方案之一,对ADV初治应答不佳患者和LAM耐药的ADV应答不佳患者的临床疗效略有差异。然而多项体外研究显示TDF对ADV耐药病毒株抑制作用减弱。ADV应答不佳的患者换用TDF是否会引起或加重肾损害值得临床关注。本文就TDF对ADV应答不佳患者挽救治疗的国内外研究进展作综述,为提高耐药HBV感染防治的管理提供帮助。     

Randomized prospective study showing the non‐inferiority of tenofovir to entecavir in treatment‐naïve chronic hepatitis B patients

Aim

The study aimed to evaluate the efficacy and safety of tenofovir disoproxil fumarate (TDF) and entecavir hydrate (ETV) in nucleos(t)ide analog (NA)‐naïve Japanese chronic hepatitis B (CHB) patients.

Methods

This multicenter, randomized, double‐blinded study assessing the efficacy and safety of TDF 300 mg and ETV 0.5 mg in NA‐naïve CHB subjects was carried out from November 2011 to November 2014, and funded by GlaxoSmithKline. The subjects were assigned to the TDF arm or ETV arm in a 2:1 ratio. The primary efficacy endpoint was the non‐inferiority of TDF to ETV at week 24.

Results

A total of 166 subjects (TDF arm, 110; ETV arm, 56) were enrolled. The change (mean ± SE) in serum hepatitis B virus (HBV)‐DNA levels from baseline to week 24 was ?4.63 ± 0.044 and ?4.50 ± 0.063 log₁₀ copies/mL in the TDF and ETV arms, respectively, indicating the non‐inferiority of TDF to ETV (P < 0.0001). The proportion of subjects with undetectable HBV‐DNA increased from 54 to 77% and 39 to 66% in the TDF and ETV arms with continuation of the treatment from week 24 to 48, respectively. Reduction in hepatitis B surface antigen level was greater in subjects with hepatitis B envelope antigen (+) and high alanine aminotransferase levels (≥80 IU/L). Prevalence of drug‐related adverse events at week 48 was 20% and 18% in the TDF and ETV arms, respectively.

Conclusions

The study is the first to report that TDF has non‐inferiority to ETV in treatment effectiveness (lowering of serum HBV‐DNA level) at week 24. ClinicalTrials.gov trial registration nos. NCT01480284 and GSK LOC115409.     

替诺福韦酯治疗慢性乙型肝炎的最新进展

核苷(酸)类似物抗病毒药物已广泛应用于慢性乙型肝炎的治疗,其中替诺福韦酯作为一种新型药物,以其良好的抗病毒作用及低耐药性成为目前研究的热点.本文概述了近年来替诺福韦酯的体内外研究进展及其在临床应用的前景.     

替诺福韦酯治疗34例慢性乙型肝炎核苷(酸)类似物经治患者的临床分析

目的观察替诺福韦酯(TDF)对慢性乙型肝炎(CHB)核苷(酸)类似物经治患者的临床疗效。方法回顾性分析TDF治疗34例CHB核苷(酸)类似物经治患者48周的临床资料,其中原发治疗失败患者18例、抗病毒耐药患者16例。分析第12、24、48周时HBV DNA阴转率、ALT复常率和48周的HBeAg血清转换率以及不良事件发生率。两组间比较采用t检验,多组间比较采用单因素方差分析。结果第12、24、48周的HBV DNA阴转率分别为35.3%、67.6%和94.1%。治疗前及治疗第12、24、48周的ALT分别为(63.9±18.9)、(49.8±11.9)、(42.7±7.3)和(35.1±3.9)U/L,治疗前后比较,差异有统计学意义(F=36.3,P0.05),48周时ALT复常率为91.1%。第48周时HBeAg阴转率为25%,HBeAg血清转换率为20%。治疗期间,随访各时间点病毒学突破率为0,肌酸激酶(CK)超过正常上限(ULN)2倍发生率0。血肌酐(Scr)治疗前为(75.1±11.1)μmol/L,治疗48周时为(76.8±10.8)μmol/L,差异无统计学意义(t=0.578,P=0.565)。Scr超过ULN发生率0。骨密度变化发生率0,血磷低于ULN发生率0。结论对于核苷(酸)类药物应答不佳和耐药的CHB患者,TDF单药治疗能有效抑制病毒,且ALT复常率高,不良事件发生率低。     

Efficacy and safety of telbivudine and tenofovir disoproxil fumarate in preventing hepatitis B vertical transmission: A real‐life practice

Mother‐to‐child transmission (MTCT) is a major obstacle in the elimination of hepatitis B virus (HBV) infection. Telbivudine (LdT) and tenofovir disoproxil fumarate (TDF) are the two most common antiviral medicines for preventing MTCT. However, the efficacy and safety of LdT and TDF in preventing HBV vertical transmission during the second to third trimester have not been compared rigorously. Therefore, we carried out a prospective multicentre cohort study of chronic hepatitis B in mothers with HBV DNA > 10⁶ IU/mL, receiving LdT or TDF during the second to third trimester. Among the 893 mothers enrolled, 857 (LdT/TDF/untreated group (NTx) = 396/325/136) completed consecutive follow‐up with 854 infants (LdT/TDF/NTx = 395/323/136). LdT and TDF treatment resulted in a similar decrease of HBV DNA in mothers at delivery. Multivariate analysis indicated that only HBsAg titre at the baseline correlated with viral DNA decrease (P = 0.015). With intention‐to‐treat analysis, MTCT rates in the LdT, TDF and NTx group were 4.41%, 2.42% and 22.08%, respectively. An increasing vertical transmission rate was found to be closely associated with higher HBsAg titre, 5.32% and 17.65% infection rate was estimated in infants born to mothers with HBsAg > 4 and >5 log₁₀ IU/mL, respectively. No serious side effects were reported in either mothers or infants. LdT and TDF treatments were well tolerated and showed comparable efficacy in reducing MTCT. Higher risk of MTCT was shown in pregnant women with HBsAg > 4 log₁₀IU/mL.     

Renal safety of tenofovir disoproxil fumarate and entecavir with hepatitis B immunoglobulin in liver transplant patients

Potent nucleos(t)ide analogues and hepatitis B immunoglobulin combinations are recommended after liver transplantation to prevent the recurrence of hepatitis B virus (HBV). Despite its proven efficacy, the renal safety of tenofovir disoproxil fumarate (TDF) has not been well established in liver transplant recipients. We aimed to assess the impacts of TDF and entecavir (ETV) on tubular and glomerular functions. We analysed 206 liver transplant patients treated with TDF (n = 102) or ETV (n = 104) plus hepatitis B immunoglobulin. Serum creatinine, phosphate and uric acid levels were measured. Proximal tubular dysfunction was defined as the presence of hypophosphatemia (<2 mg/dL) and hypouricemia (<2 mg/dL). Glomerular dysfunction was defined as an estimated glomerular filtration rate (eGFR) of <60 mL/min/1.73 m² accompanied by a ≥25% eGFR decline from baseline. During a median follow‐up of 42.5 months, 48 patients developed proximal tubular dysfunction (30.4% and 16.3% in the TDF and ETV groups; P = .017). Serum levels of phosphate and uric acid were significantly lower in the TDF group post‐LT. TDF (OR, 2.34; 95% CI, 1.16‐4.69; P = .017) and low body mass index (OR, 2.11; 95% CI, 1.06‐4.21; P = .034) were independent risk factors for proximal tubular dysfunction. The prevalence of glomerular dysfunction was not significantly different between the two groups (TDF 51.0% and ETV 54.8%; P = .582). TDF significantly increased the risk of proximal tubular dysfunction. Although the effect of TDF on glomerular function was comparable to that of ETV, glomerular dysfunction was common after liver transplant.     

Improvement of bone mineral density and markers of proximal renal tubular function in chronic hepatitis B patients switched from tenofovir disoproxil fumarate to tenofovir alafenamide

Tenofovir alafenamide (TAF) is a novel prodrug that reduces tenofovir plasma levels by 90% compared to tenofovir disoproxil fumarate (TDF), resulting in decreased bone mineral density (BMD) loss and renal toxicity. We aimed to study changes in BMD and markers of renal function of chronic hepatitis B (CHB) patients previously treated with TDF who were switched to TAF in as early as 12 weeks. This was a prospective single‐arm open‐label study of 75 CHB patients treated with TDF 300 mg daily who were switched to TAF 25 mg daily and followed for 24 weeks. All patients had been treated with TDF for at least 12 months and had HBV DNA <21 IU/mL at the time of switch. BMD and markers of renal function were taken on the day of switch and repeated after 12 and 24 weeks of TAF treatment. Hip and spine bone mineral density significantly increased from baseline to week 12 (+12.9% and +2.4%, respectively, P < 0.01). There were significant decreases in urinary beta‐2‐microglobulin to creatinine and retinol‐binding protein to creatinine ratios by week 12 (P < 0.01 for both). Mean estimated glomerular filtration rate (GFR) did not change. Tubular reabsorption of phosphate was decreased at week 24 (P < 0.05). In conclusion, CHB patients previously treated with TDF experienced significant improvement in bone density and some markers of renal tubular function and as early as 12 weeks after switching to TAF. Bone density changes associated with TDF may not be entirely related to renal handling of phosphate.     

Tenofovir disoproxil fumarate vs adefovir dipivoxil in Chinese patients with chronic hepatitis B after 48 weeks: a randomized controlled trial

Tenofovir disoproxil fumarate (TDF) has demonstrated long‐term efficacy and a high barrier to resistance in multiple chronic hepatitis B (CHB) populations outside of China. This study aimed to evaluate the efficacy and safety of TDF compared with adefovir dipivoxil (ADV) in Chinese patients with CHB during 48 weeks of treatment (ClinicalTrial.gov number, NCT01300234). A Phase 3, multicentred, randomized, double‐blind, controlled trial compared the efficacy and safety of TDF with ADV in Chinese patients with CHB. The primary endpoint was the proportion of patients with HBV DNA <400 copies/mL in each treatment group at Week 48, using an unpooled Z‐test for superiority. Secondary endpoints included viral suppression, serologic response, histological improvement, normalization of alanine aminotransferase (ALT) levels and the emergence of resistance mutations. A total of 509 patients, 202 hepatitis B e antigen (HBeAg)‐positive and 307 HBeAg‐negative, with HBV DNA ≥10⁵ copies/mL received either TDF 300 mg od or ADV 10 mg od. At Week 48, TDF demonstrated superior viral suppression compared with ADV in both HBeAg‐positive (76.7% vs 18.2%, P < 0.0001) and HBeAg‐negative (96.8% vs 71.2%, P < 0.0001) patients. The majority of patients in both treatment arms achieved ALT normalization (>85%). No resistance to TDF was observed. The frequency of adverse events was comparable between treatment arms (TDF 3.9% vs ADV 4.8%). In this double‐blind, randomized, clinical trial, TDF demonstrated superiority over ADV with respect to viral suppression in Chinese patients with CHB at 48 weeks of treatment and without the development of resistance.