Comparison of fibrosis regression of entecavir alone or combined with pegylated interferon alpha2a in patients with chronic hepatitis B

Liver fibrosis showed a two-phase regression rate during long-term anti-HBV therapy by three-time biopsies assessments

BACKGROUND

Evidence has proven that liver fibrosis or even cirrhosis can be reversed by anti-HBV treatment. However, the difference of fibrosis regression rates in short-term and long-term antiviral therapy remain unclear. Therefore, we aimed to identify the dynamic changes in fibrosis regression rate in patients with three-time liver biopsies during 5 years antiviral therapy.

METHODS

CHB patients with three times of liver biopsies (baseline, after 1.5-year and 5-year antiviral therapy) from a prospective cohort were enrolled. All patients were biopsy-proved Ishak stage ≥ 3 at baseline (n = 92). Fibrosis regression was defined as Ishak stage decreased ≥ 1 or predominantly regressive categorized by P-I-R score.

RESULTS

Totals of 65.2% (60/92) and 80.4% (74/92) patients attained fibrosis regression after 1.5-year and 5-year therapy, respectively. Median HBV DNA level declined from 6.5 log IU/ml (baseline) to 0 log IU/ml (1.5 years and 5 years, P < 0.001). The mean level of Ishak fibrosis stage in all patients decreased from stage 4.1 (baseline) to 3.7 (1.5 years) then 3.2 (5 years). Fibrosis regression rates were 0.27 stage/year between baseline to year 1.5 and 0.14 stage/year between year 1.5 and year 5. Furthermore, for patients who attained fibrosis regression after 5-year antiviral therapy, the two-phase regression rates were 0.39 stage/year (0 year-1.5 years) and 0.20 stage/year (1.5 years-5 years). This two-phase feature of regression rate was further confirmed by fully-quantification assessment of liver fibrosis based on SHG/TPEF.

CONCLUSION

During the 5 years of long-term antiviral treatment, liver fibrosis rapidly regresses in the first 1.5 years before slowing down in the following 3.5 years.

Sevelamer reverses liver fibrosis by deactivation of hepatic stellate cells

Liver fibrosis is a chronic liver disease characterized by a progressive wound healing response caused by chronic liver injury. Currently, there are no approved clinical treatments for liver fibrosis. Sevelamer is used clinically to treat hyperphosphatemia and has shown potential therapeutic effects on liver diseases. However, there have been few studies evaluating the therapeutic effects of sevelamer on liver fibrosis, and the specific mechanisms are still unclear. In this study, we investigated the antifibrotic effects of sevelamer-induced low inorganic phosphate (Pi) stress in vitro and in vivo and analyzed the detailed mechanisms. We found that low Pi stress could inhibit the proliferation of activated hepatic stellate cells (HSCs) by promoting apoptosis, effectively suppressing the migration and epithelial-mesenchymal transition (EMT) of hepatic stellate cells. Additionally, low Pi stress significantly increased the antioxidant stress response. It is worth noting that low Pi stress indirectly inhibited the activation and migration of HSCs by suppressing transforming growth factor β (TGF-β) expression in macrophages. In a rat model of liver fibrosis, oral administration of sevelamer significantly decreased blood phosphorus levels, improved liver function, reduced liver inflammation, and increased the antioxidant stress response in the liver. Our study revealed that the key mechanism by which sevelamer inhibited liver fibrosis involved binding to gastrointestinal phosphate, resulting in a decrease in blood phosphorus levels, the downregulation of TGF-β expression in macrophages, and the inhibition of HSC migration and fibrosis-related protein expression. Therefore, our results suggest that sevelamer-induced low Pi stress can attenuate hepatic stellate cell activation and inhibit the progression of liver fibrosis, making it a potential option for the treatment of liver fibrosis and other refractory chronic liver diseases.

Regression of Liver Fibrosis in Patients on Hepatitis B Therapy Is Associated With Decreased Liver-Related Events

BACKGROUND & AIMS

Liver fibrosis in patients with chronic hepatitis B can regress with successful antiviral therapy. However, the long-term clinical benefits of fibrosis regression have not been fully elucidated. This study investigated the association between biopsy-proven fibrosis regression by predominantly progressive, indeterminate, and predominantly regressive (P-I-R) score and liver-related events (LREs) in chronic hepatitis B patients.

METHODS

Patients with on-treatment liver biopsy and significant fibrosis/cirrhosis (Ishak stage ≥3) were included in this analysis. Fibrosis regression was evaluated according to the P-I-R score of the Beijing Classification. LREs were defined as decompensations, hepatocellular carcinoma, liver transplantation, or death. The Cox proportional hazards model was used to determine associations of fibrosis regression with LREs.

RESULTS

A total of 733 patients with Ishak stages 3/4 (n = 456; 62.2%) and cirrhosis (Ishak stages 5/6; n = 277; 37.8%) by on-treatment liver biopsy were enrolled. According to the P-I-R score, fibrosis regression, indeterminate, and progression were observed in 314 (42.8%), 230 (31.4%), and 189 (25.8%) patients, respectively. The 7-year cumulative incidence of LREs was 4.1%, 8.7%, and 18.1% in regression, indeterminate, and progression, respectively (log-rank, P < .001). Compared with patients with fibrosis progression, those with fibrosis regression had a lower risk of LREs (adjusted hazard ratio, 0.40; 95% CI, 0.16-0.99; P = .047), followed by the indeterminate group (adjusted hazard ratio, 0.86; 95% CI, 0.40-1.85; P = .691). Notably, this favorable association also was observed in patients with cirrhosis or low platelet counts (<150 × 109/L).

CONCLUSIONS

Antiviral therapy-induced liver fibrosis regression assessed by P-I-R score is associated with reduced LREs. This shows the utility of histologic fibrosis regression assessed by on-treatment P-I-R score as a surrogate endpoint for clinical events in patients with hepatitis B virus-related fibrosis or early cirrhosis.

The utility of P-I-R classification in predicting the on-treatment histological and clinical outcomes of patients with hepatitis B and advanced liver fibrosis

BACKGROUND AND AIMS

The predominantly progressive, indeterminate, and predominantly regressive (P-I-R) classification extends beyond staging and provides information on dynamic changes of liver fibrosis. However, the prognostic implication of P-I-R classification is not elucidated. Therefore, in the present research, we investigated the utility of P-I-R classification in predicting the on-treatment clinical outcomes.

APPROACH AND RESULTS

In an extension study on a randomized controlled trial, we originally enrolled 1000 patients with chronic hepatitis B and biopsy-proven histological significant fibrosis, and treated them for more than 7 years with entecavir-based therapy. Among the 727 patients with a second biopsy at treatment week 72, we compared P-I-R classification and Ishak score changes in 646 patients with adequate liver sections for the histological evaluation. Progressive, indeterminate, and regressive cases were observed in 70%, 17%, and 13% of patients before treatments and 20%, 14%, and 64% after 72-week treatment, respectively, which could further differentiate the histological outcomes of patients with stable Ishak scores. The 7-year cumulative incidence of HCC was 1.5% for the regressive cases, 4.3% for the indeterminate cases, and 22.8% for the progressive cases ( p <0.001). After adjusting for age, treatment regimen, platelet counts, cirrhosis, Ishak fibrosis score changes, and Laennec staging, the posttreatment progressive had a HR of 17.77 (vs. posttreatment regressive; 95% CI: 5.55-56.88) for the incidence of liver-related events (decompensation, HCC, and death/liver transplantation).

CONCLUSIONS

The P-I-R classification can be a meaningful complement to the Ishak fibrosis score not only in evaluating the histological changes but also in predicting the clinical outcomes.

Treatment of liver fibrosis: Past, current, and future

Liver fibrosis accompanies the progression of chronic liver diseases independent of etiologies, such as hepatitis viral infection, alcohol consumption, and metabolic-associated fatty liver disease. It is commonly associated with liver injury, inflammation, and cell death. Liver fibrosis is characterized by abnormal accumulation of extracellular matrix components that are expressed by liver myofibroblasts such as collagens and alpha-smooth actin proteins. Activated hepatic stellate cells contribute to the major population of myofibroblasts. Many treatments for liver fibrosis have been investigated in clinical trials, including dietary supplementation (e.g., vitamin C), biological treatment (e.g., simtuzumab), drug (e.g., pegbelfermin and natural herbs), genetic regulation (e.g., non-coding RNAs), and transplantation of stem cells (e.g., hematopoietic stem cells). However, none of these treatments has been approved by Food and Drug Administration. The treatment efficacy can be evaluated by histological staining methods, imaging methods, and serum biomarkers, as well as fibrosis scoring systems, such as fibrosis-4 index, aspartate aminotransferase to platelet ratio, and non-alcoholic fatty liver disease fibrosis score. Furthermore, the reverse of liver fibrosis is slowly and frequently impossible for advanced fibrosis or cirrhosis. To avoid the life-threatening stage of liver fibrosis, anti-fibrotic treatments, especially for combined behavior prevention, biological treatment, drugs or herb medicines, and dietary regulation are needed. This review summarizes the past studies and current and future treatments for liver fibrosis.

The association between hepatocarcinogenesis and intracellular alterations due to hepatitis B virus infection

Chronic hepatitis B virus (HBV) infection is a worldwide health problem leading to severe liver dysfunction, including liver cirrhosis and hepatocellular carcinoma. Although current antiviral therapies for chronic HBV infection have been improved and can lead to a strong suppression of viral replication, it is difficult to completely eliminate the virus with these therapies once chronic HBV infection is established in the host. Furthermore, chronic HBV infection alters intracellular metabolism and signalling pathways, resulting in the activation of carcinogenesis in the liver. HBV produces four viral proteins: hepatitis B surface-, hepatitis B core-, hepatitis B x protein, and polymerase; each plays an important role in HBV replication and the intracellular signalling pathways associated with hepatocarcinogenesis. In vitro and in vivo experimental models for analyzing HBV infection and replication have been established, and gene expression analyses using microarrays or next-generation sequencing have also been developed. Thus, it is possible to clarify the molecular mechanisms for intracellular alterations, such as endoplasmic reticulum stress, oxidative stress, and epigenetic modifications. In this review, the impact of HBV viral proteins and intracellular alterations in HBV-associated hepatocarcinogenesis are discussed.