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

Sustained antiviral effects and clearance of hepatitis surface antigen after combination therapy with entecavir and pegylated interferon in chronic hepatitis B

BACKGROUND

Although the efficacy of combination therapy with lamivudine or tenofovir and pegylated interferon (PEG-IFN) has been reported in patients with chronic hepatitis B (CHB), the long-term effect of the combination based on the observation of clinical course remains to be clarified. We previously reported the efficacy of combination therapy with entecavir (ETV) and PEG-IFN. Here, we investigated the long-term effect of this combination in patients with CHB.

METHODS

We administered both ETV and PEG-IFN-α2a or -2b simultaneously to 26 patients with HBV genotype C infection. Treatment was continued for 48 weeks followed by 24 weeks of observation period; we examined the virological and biochemical responses. We also analysed characteristics related to the post-treatment relapse. Finally, we investigated the long-term therapeutic effects.

RESULTS

Average reduction of intra-hepatic cccDNA level was 1.2 log copies/μg at the completion of administration. Pretreatment hepatitis B surface antigen (HBsAg) level with more than 3.5 log U/ml was identified as a predictive factor for relapse. Furthermore, the cumulative rates of HBsAg-negative patients at 1, 3 and 5 years after the completion of administration were 3.8, 8.4 and 15%, respectively (mean follow-up period: 4.8 years).

CONCLUSIONS

Baseline HBsAg level with more than 3.5 log U/ml is a useful predictor for relapse 24 weeks after the completion of administration in patients treated with combination therapy. Combination with ETV and PEG-IFN could be an option for treatment of CHB patients especially in those with baseline HBsAg levels of less than 3.5 log U/ml.

A multicenter study of entecavir vs. tenofovir on prognosis of treatment-naïve chronic hepatitis B in South Korea

BACKGROUND & AIMS

It is currently unclear which antiviral agent, entecavir (ETV) or tenofovir disoproxil fumarate (TDF), is superior for improving prognosis in patients with chronic hepatitis B (CHB). Here, we assessed the ability of these 2 antivirals to prevent liver-disease progression in treatment-naïve patients with CHB.

METHODS

From 2012 to 2014, treatment-naïve patients with CHB who received ETV or TDF as a first-line antiviral agent were recruited from 4 academic teaching hospitals. Patients with decompensated cirrhosis or hepatocellular carcinoma (HCC) at enrollment were excluded. Cumulative probabilities of HCC and death or orthotopic liver transplant (OLT) were assessed.

RESULTS

In total, 2,897 patients (1,484 and 1,413 in the ETV and TDF groups, respectively) were recruited. The annual HCC incidence was not statistically different between the ETV and TDF groups (1.92 vs. 1.69 per 100 person-years [PY], respectively; adjusted hazard ratio [HR] 0.975 [p = 0.852] by multivariate analysis). Propensity score (PS)-matched and inverse probability of treatment weighting (ITPW) analyses yielded similar patterns of results (HR 1.021 [p = 0.884] and 0.998 [p = 0.988], respectively). The annual incidence of death or OLT was not statistically different between the ETV and TDF groups (0.52 vs. 0.53 per 100 PY, respectively; adjusted HR 1.202 [p = 0.451]). PS-matched and ITPW analyses yielded similar patterns of results (HR 1.248 [p = 0.385] and 1.239 [p = 0.360], respectively). These findings were consistently reproduced in patients with compensated cirrhosis (all p >0.05).

CONCLUSIONS

The overall prognosis in terms of HCC and death or OLT was not statistically different between the ETV and TDF groups. Further studies are needed to validate our results.

LAY SUMMARY

It is currently unclear which antiviral agent, entecavir or tenofovir disoproxil fumarate, is superior for improving prognosis in patients with chronic hepatitis B virus infection. In this analysis we found that there was no difference in terms of overall prognosis, including risk of hepatocellular carcinoma, death, or the need for a liver transplant, in patients receiving either antiviral.

Antiviral treatment for treatment-naïve chronic hepatitis B: systematic review and network meta-analysis of randomized controlled trials

BACKGROUND

Chronic hepatitis B (CHB) infection poses a significant burden to public health worldwide. Most cases are clinically silent until late in the disease course. The main goal of current therapy is to improve survival and quality of life by preventing disease progression to cirrhosis and liver failure, and consequently hepatocellular carcinoma development. The objective of this review is to provide a contemporary and comprehensive evaluation of the effectiveness of treatment options.

METHODS

We performed a systematic review of peer-reviewed literature for randomized controlled trials involving treatment-naïve CHB adult population who received antiviral therapy. The endpoints were virologic response (VR), normalization of alanine aminotransferase (ALT norm), HBeAg loss, HBeAg seroconversion, and HBsAg loss for the HBeAg-positive population; and VR and ALT norm for the HBeAg-negative population. Network meta-analysis (NMA) was performed to synthesize evidence on the efficacy of treatment.

RESULTS

Forty-two publications were selected. Twenty-three evaluated HBeAg-positive population, 13 evaluated HBeAg-negative population, and six evaluated both. We applied NMA to the efficacy outcomes of the two populations separately. Treatment strategies were ranked by the probability of achieving outcomes, and pairwise comparisons calculated from NMA were reported in odds ratios (OR). For HBeAg-positive population, tenofovir disoproxil fumarate (TDF) and tenofovir alafenamide (TAF) were the best for VR; OR vs adefovir = 14.29, 95% CI 7.69-25 and 12.5, 95% CI 4.35-33.33 respectively. TAF was the best for achieving ALT norm (OR vs placebo = 12.5, 95% CI 4.55-33.33), HBeAg loss, and seroconversion (OR vs entecavir/TDF combination = 3.03, 95% CI 1.04-8.84 and 3.33, 95% CI 1.16-10 respectively). In the HBeAg-negative population, TDF and TAF were the best for VR (OR vs adefovir = 9.79, 95% CI 2.38-42.7 and 11.71, 95% CI 1.03-150.48 respectively). Telbivudine and TAF were the best for ALT norm. Certain nucleos(t)ide combinations also had high probability of achieving positive outcomes.

CONCLUSIONS

Our results are consonant with current clinical guidelines and other evidence reviews. For both HBeAg-positive and HBeAg-negative populations, TDF and TAF are the most effective agents for virologic suppression, and TAF is effective across all outcomes.

Switching from entecavir to tenofovir alafenamide versus maintaining entecavir for chronic hepatitis B

Tenofovir alafenamide (TAF) is a newly developed prodrug of tenofovir (TFV). We divided 48 chronic hepatitis B patients who had taken entecavir (ETV) for ≥2 years into two groups: the ETV continuation (n = 24) and the TAF switching (n = 24) groups, and compared the antiviral effects and safety until 48 weeks after the start of the study. There were no significant differences in the alterations in the serum levels of HBs antigen (HBsAg) level between the ETV continuation and the TAF switching groups at 24 or 48 weeks. We also examined the effect of baseline HBsAg level on the decrease of HBsAg during the treatment; in the TAF switching group, the decrease of HBsAg level at 48 weeks was more significant in patients with low baseline HBsAg (<800 IU/mL) than those with high baseline HBsAg ( >800 IU/mL) (change of HBsAg; - 0.029 vs - 0.132 for high and low baseline HBsAg, respectively, P = .007). Also, the effect on renal function was found to be comparable between the TAF switch group and the ETV continuation group. In this study, switching from ETV to TAF may represent higher efficacy for a decrease of HBsAg than a continuation of ETV among the patients with low baseline HBsAg level.

Switching to tenofovir disoproxil fumarate vs continuing treatment in patients with chronic hepatitis B who maintain long-term virological response to entecavir therapy: A randomized trial

No controlled trial in patients with chronic hepatitis B virus (HBV) infection on long-term entecavir (ETV) treatment, comparing switching to tenofovir disoproxil fumarate (TDF) with continuing the therapy, has been reported. Twenty-seven nucleos(t)ide-naïve patients with chronic HBV who underwent ETV therapy for ≥5 years and maintained virological response were included and randomized into two groups: one group continued ETV, and the other switched to TDF, in a 1:2 ratio. The primary endpoint was changed from baseline in serum hepatitis B surface antigen (HBsAg) level at week 48. The baseline characteristics were not different between nineteen patients in the TDF group and eight patients in the ETV group. Mean decreases in HBsAg level at week 48 were 0.023 and 0.042 log₁₀  IU/mL in the TDF and ETV groups, respectively (P = 0.94). The mean drops in hepatitis B core-related antigens were also not different between the TDF and ETV groups at week 48 (P = 0.80). HBV DNA was sustainedly <2.1 log ₁₀  copies/mL in all patients throughout the study period. In contrast, the mean aminotransferase levels were significantly higher in the TDF group than in the ETV group at weeks 12, 24, and 36, although being within the reference range. Estimated glomerular filtration rate was lower in the TDF group than in the ETV group at weeks 24 (P = 0.016) and 48 (P = 0.003). In conclusion, we could not find the effect on reducing HBsAg level by switching to TDF in chronic hepatitis B patients with maintained virological response to ETV for ≥5 years.