Hepatitis B virus genotype B is associated with better response to thymosin alpha1 therapy than genotype C

Safety and efficacy of Thymosin α1 in the treatment of hepatitis B virus-related acute-on-chronic liver failure: a randomized controlled trial

BACKGROUND/PURPOSE OF THE STUDY

Mortality from hepatitis B virus (HBV)-related acute-on-chronic liver failure (ACLF) is high. Severe infection is the most important complication that affects the outcomes of ACLF patients. Thymosin α1 (Tα1) can improve immune imbalance and this study aimed to investigate the safety and efficacy of Tα1 treatment for HBV-related ACLF.

METHODS

From 2017 to 2019, 120 patients with HBV-related ACLF were enrolled in this open-label, randomized, and controlled clinical trial (ClinicalTrial ID: NCT03082885). The control group (N = 58) was treated with standard medical therapy (SMT) only. The experimental group (N = 56) was subcutaneously injected with 1.6 mg of Tα1 once a day for the first week and then twice a week from week 2 to week 12.

RESULTS

The 90-day cumulated liver transplantation free survival rate of the Tα1 group was 75.0% (95% confidence interval 63.2-86.8%) versus 53.4% (95% confidence interval 39.7-67.1%) for the SMT group (p = 0.030). No significant difference was found in the survival using competitive risk analysis. The incidences of new infection and hepatic encephalopathy in the Tα1 group were much lower than those in the SMT group (32.1% vs 58.6%, p = 0.005; 8.9% vs 24.1%, p = 0.029, respectively). Mortality from severe infection in the SMT group was higher than in the Tα1 group (24.1% vs 8.9%, p = 0.029).

CONCLUSION

Tα1 is safe for patients with HBV-related ACLF and significantly improves the 90-day liver transplantation-free survival rate. There may be a subgroup which may benefit from Tα1 therapy by the mechanism of preventing infection.

Specific in vitro binding of a new (99m)Tc-radiolabeled derivative of the C-terminal decapeptide of prothymosin alpha on human neutrophils

Prothymosin alpha (ProTα) is a conserved mammalian polypeptide with intracellular functions associated with cell proliferation and apoptosis and an extracellular role associated with immunopotentiation. The N-terminal fragment [1-28], which is identical with the immunostimulating peptide thymosin α1 (Tα1), was earlier considered as the immunoactive region of the polypeptide; however, recent data suggest that ProTα may exert a discrete immunomodulating action through its central or C-terminal region, via targeting Toll-like receptor- 4 (TLR4). In this work, a derivative of the C-terminal fragment ProTα[100-109] (ProTα-D1) that can be radiolabeled with (99m)Tc was developed. The biological activity of the non-radioactive (185/187)rhenium-complex of this derivative ([(185/187)Re]ProTα-D1, structurally similar with [(99m)Tc]ProTα-D1) was verified through suitable in vitro bioassays on human neutrophils. Subsequent cell-binding studies revealed specific, time-dependent and saturable binding of [(99m)Tc]ProTα-D1 on neutrophils, which was inhibited by intact ProTα and ProTα[100-109], as well as by a "prototype" TLR4-ligand (lipopolysaccharide from Escherichia coli). Overall, our results support the existence of ProTα-binding sites on human neutrophils, recognizing [(99m)Tc]ProTα-D1, which might involve TLR4. [(99m)Tc]ProTα-D1 may be a useful tool for conducting further in vitro and in vivo studies, aiming to elucidate the extracellular mode of action of ProTα and, eventually, develop ProTα-based immunotherapeutics.

Micro-evolution of the hepatitis B virus genome in hepatitis B e-antigen-positive carriers: comparison of genotypes B and C at various immune stages

BACKGROUND AND AIM

Patients with hepatitis B virus (HBV) genotype B infection experience hepatitis B e-antigen (HBeAg) seroconversion at an earlier stage than do patients with genotype C infection. Therefore, this study investigated whether the differential phenotypes are related to HBV genomic evolution.

METHODS

Thirty-three HBeAg-positive patients with a mean follow-up of 3.1 years were enrolled: 16 at the immune tolerance stage (group I) and 17 at the immune clearance stage (group II). The evolution rates of paired viral genomes at enrollment and at the final follow-up in the full-length genome (μf), nonoverlapping regions (synonymous [μs] and nonsynonymous [μa]), and overlapping regions (μ) were calculated. The evolution rates were then compared according to serum alanine aminotransferase (ALT) levels and HBV genotype.

RESULTS

The overall μf evolution rate was lower in group I than in group II (1.4 × 10(-5)  ± 3.3 × 10(-5) vs 1.2 × 10(-3)  ± 1.2 × 10(-3) nucleotide substitution/site/year, P < 0.001). We observed similar results for the μs, μa, and μ evolution rates. All evolution parameters were comparable between genotypes B and C. We determined a positive correlation between μa/y and the area under the average ALT time curve in genotype B (R(2)  = 0.6935, P < 0.0001), but not in genotype C (R(2)  = 0.1606, P = 0.124).

CONCLUSION

The evolution rate of the HBV genome is higher at the immune clearance stage than at the immune tolerance stage. Host immune selection might play a role in triggering evolution of genotype B.

Distribution and diversity of hepatitis B virus genotypes in Yunnan, China

Hepatitis B virus (HBV) is one of the most prevalent pathogens in the world, and infection with this virus is a serious threat for public health. Yunnan is considered as an important endemic center for blood-borne viruses such as human immunodeficiency virus and hepatitis C virus, in China. However, the distribution and diversity of HBV subgenotypes remain unclear in Yunnan province. In the current study, HBV positive samples were collected from different prefectures of Yunnan province and their molecular epidemiological characters were determined. Phylogenetic analysis on the pre-S/S gene (865 bps) showed the prevalence of four HBV genotypes, including genotype B (24 cases, 33.3%), genotype C (45 cases, 62.5%), genotype I (two cases, 2.78%) and C/D recombinants (one case, 1.39%). The most prevalent genotypes B and C could be sub classified into subgenotype B2 and C1, C2, C5, and C7, respectively. Clusters of subgenotype B2 and C2 consisted of strains from China and other East Asian countries, while subgenotype C1, C5, and C7 and genotype I formed a cluster together with strains from Southeast Asia. Using Bayesian inference from phylogenetic, HBV genotypes B and C were estimated to have originated in 1860s and 1910s with an evolutionary rate of 3.26 and 8.01 × 10(-4) substitutions/site/year, respectively. These findings indicate that the distribution of HBV genotypes in Yunnan was influenced by strains from the rest of China and the neighboring countries.

Efficacy of thymosin α-1 plus peginterferon α-2a combination therapy compared with peginterferon α-2a monotherapy in HBeAg-positive chronic hepatitis B: a prospective, multicenter, randomized, open-label study

OBJECTIVE

Thymosin α-1 plus interferon α-2a offers superior efficacy over interferon α-2a alone in patients with chronic hepatitis B. The aim was to compare the antiviral efficacy of thymosin α-1 plus peginterferon α-2a and peginterferon α-2a alone in HBeAg-positive chronic hepatitis B patients.

MATERIALS AND METHODS

HBeAg-positive CHB patients were enrolled in this prospective, randomized, open-label study. Fifty-one patients were assigned to either combination (26 patients; 180 μg of peginterferon α-2a weekly for 48 weeks and 1.6 mg of thymosin α-1 twice a week for the first 12 weeks) or monotherapy (25 patients; 180 μg of peginterferon α-2a weekly for 48 weeks) groups.

RESULTS

The rates of the combined response, defined as HBeAg seroconversion, HBV DNA suppression, and normalization of serum ALT, were 4/26 (15.4%) and 3/25 (12.0%) for the combination group and the monotherapy group at the end of treatment (p = 0.725), and 6/26 (23.1%) and 5/25 (20.0%) at the end of follow-up (p = 0.789), respectively. Based on multiple logistic regression analysis, a >2 log₁₀ IU/mL reduction of HBV DNA at week 12 was identified as an independent predictor for combined response (OR, 9.72; 95% CI, 1.33-71.06; p = 0.025) at the end of follow-up. A lower pretreatment HBV DNA level (≤ 7 log(10) IU/mL) was another predictor for combined response (OR, 9.64; 95% CI, 1.23-75.32; p = 0.031). No significant differences in adverse events were observed.

CONCLUSIONS

The short-term addition of thymosin α-1 was not superior to peginterferon α-2a alone in HBeAg-positive CHB patients on the basis of antiviral efficacy.

Asian-Pacific consensus statement on the management of chronic hepatitis B: a 2012 update

Large volume of new data on the natural history and treatment of chronic hepatitis B virus (HBV) infection have become available since 2008. These include further studies in asymptomatic subjects with chronic HBV infection and community-based cohorts, the role of HBV genotype/naturally occurring HBV mutations, the application of non-invasive assessment of hepatic fibrosis and quantitation of HBV surface antigen and new drug or new strategies towards more effective therapy. To update HBV management guidelines, relevant new data were reviewed and assessed by experts from the region, and the significance of the reported findings was discussed and debated. The earlier "Asian-Pacific consensus statement on the management of chronic hepatitis B" was revised accordingly. The key terms used in the statement were also defined. The new guidelines include general management, indications for fibrosis assessment, time to start or stop drug therapy, choice of drug to initiate therapy, when and how to monitor the patients during and after stopping drug therapy. Recommendations on the therapy of patients in special circumstances, including women in childbearing age, patients with antiviral drug resistance, concurrent viral infection, hepatic decompensation, patients receiving immune suppression or chemotherapy and patients in the setting of liver transplantation and hepatocellular carcinoma, are also included.

Antiviral therapy in patients with concomitant chronic hepatitis B and autoimmune diseases

Chronic hepatitis B with concomitant autoimmune diseases is clinically common, and most of these patients need antiviral treatment. Each type of anti-HBV agent, such as nucleos(t)ide analogues and interferon-α, has its own unique advantages and disadvantages. Before selecting optimal antiviral therapy, we should evaluate these patients adequately to avoid iatrogenic injuries. For example, which autoimmune disease is the patients suffering from? How serious is the disease?

Potential Role of Thymosin-alpha1 Adjuvant Therapy for Glioblastoma

Glioblastomas are high-grade, malignant CNS neoplasms that are nearly always fatal within 12 months of diagnosis. Immunotherapy using proinflammatory cytokines such as IL-2 or IL-12 may prolong survival with glioblastoma. Thymosin-α1 (Talpha1) is a thymic hormone and immunemodulator that increase IL-2 production and T-cell proliferation. We examined potential therapeutic effects of Talpha1 in experimental in vivo glioblastoma, and characterized Talpha1's anti-tumor effects in vitro. Rar 9L cells (10⁴) were implanted into the right frontal lobe of adult Long Evans rats that were subsequently treated with vehicle, BCNU, Talpha1, or Talpha1+BCNU from postoperative day 6. Talpha1+BCNU significantly lowered tumor burdens, and increased cure rates. In vitro experiments demonstrated that Talpha1 had no direct effect on viability or mitochondrial function, and instead, it increased expression of pro-apoptosis genes, including FasL, FasR and TNFα-R1 (65.89%, 44.08%, and 22.18%, resp.), and increased 9L cell sensitivity to oxidative stress. Moreover, Talpha1 enhanced 9L cell sensitivity to both Granzyme B- and BCNU-mediated killing. The findings suggest that Talpha1 enhances BCNUmediated eradication of glioblastoma in vivo, and that Talpha1 mediates its effects by activating pro-apoptosis mechanisms, rendering neoplastic cells more sensitive to oxidative stress and immune-mediated killing by Granzyme B and chemotherapeutic agents.

Asian-Pacific consensus statement on the management of chronic hepatitis B: a 2008 update

Large amounts of new data on the natural history and treatment of chronic hepatitis B virus (HBV) infection have become available since 2005. These include long-term follow-up studies in large community-based cohorts or asymptomatic subjects with chronic HBV infection, further studies on the role of HBV genotype/naturally occurring HBV mutations, treatment of drug resistance and new therapies. In addition, Pegylated interferon alpha2a, entecavir and telbivudine have been approved globally. To update HBV management guidelines, relevant new data were reviewed and assessed by experts from the region, and the significance of the reported findings were discussed and debated. The earlier "Asian-Pacific consensus statement on the management of chronic hepatitis B" was revised accordingly. The key terms used in the statement were also defined. The new guidelines include general management, special indications for liver biopsy in patients with persistently normal alanine aminotransferase, time to start or stop drug therapy, choice of drug to initiate therapy, when and how to monitor the patients during and after stopping drug therapy. Recommendations on the therapy of patients in special circumstances, including women in childbearing age, patients with antiviral drug resistance, concurrent viral infection, hepatic decompensation, patients receiving immune-suppressive medications or chemotherapy and patients in the setting of liver transplantation, are also included.

Asian-Pacific consensus statement on the management of chronic hepatitis B: a 2008 update

Large amounts of new data on the natural history and treatment of chronic hepatitis B virus (HBV) infection have become available since 2005. These include long-term follow-up studies in large community-based cohorts or asymptomatic subjects with chronic HBV infection, further studies on the role of HBV genotype/naturally occurring HBV mutations, treatment of drug resistance and new therapies. In addition, Pegylated interferon alpha2a, entecavir and telbivudine have been approved globally. To update HBV management guidelines, relevant new data were reviewed and assessed by experts from the region, and the significance of the reported findings were discussed and debated. The earlier "Asian-Pacific consensus statement on the management of chronic hepatitis B" was revised accordingly. The key terms used in the statement were also defined. The new guidelines include general management, special indications for liver biopsy in patients with persistently normal alanine aminotransferase, time to start or stop drug therapy, choice of drug to initiate therapy, when and how to monitor the patients during and after stopping drug therapy. Recommendations on the therapy of patients in special circumstances, including women in childbearing age, patients with antiviral drug resistance, concurrent viral infection, hepatic decompensation, patients receiving immune-suppressive medications or chemotherapy and patients in the setting of liver transplantation, are also included.

Reviews for APASL guidelines: immunomodulator therapy of chronic hepatitis B

The primary aim of immunomodulator therapy is to help the natural human immune system to mount a defense against hepatitis B virus. IFN-alpha has been used for the treatment of HBeAg-positive and HBeAg-negative chronic hepatitis B for over two decades and has been shown to be effective in suppressing HBV replication and in inducing serological response leading to long-term clinical benefits. IFN-alpha has been used in patients with well-compensated cirrhosis with comparable or better response to that in non-cirrhotic patients. IFN-alpha therapy in patients with cirrhosis has a similar side effect profile as in those without cirrhosis. However, IFN-alpha is contraindicated in patients with overt or decompensated cirrhosis. Pegylated IFN-alpha has been shown to be effective in treatment of chronic hepatitis B with sustained response rate in about one-third of the treated patients. Peg IFN-alpha treatment in non-responders to lamivudine or adefovir dipivoxil showed similar response rate to that seen in naïve patients. Thymosin alpha(1) is effective in treatment of HBeAg-positive and HBeAg-negative chronic hepatitis B with a significantly increasing virological response over time after therapy.

Genetic variability of hepatitis B virus and response to antiviral therapy

Hepatitis B virus (HBV) infection is a global health issue. Effective and individualized treatment of chronic hepatitis B to prevent progression to end-stage liver diseases and hepatocellular carcinoma is needed. HBV can be classified into eight genotypes (A-H) on the basis of genome sequence divergence. In addition, several naturally occurring HBV mutants have also been identified. The epidemiology of HBV genotypes and their implications for response to antiviral therapy have become increasingly recognized. Recent studies suggested that responses to standard interferon treatment in patients with genotype A or B are better than those with genotype C or D; however, conflicting results exist regarding the response to pegylated interferon. The influence of dose and duration on interferon-based therapy remains to be clarified. In addition to genotype, naturally occurring mutations such as precore and core promoter mutations have also attracted much attention, because they have been shown to affect the disease progression of HBV-related chronic liver disease and possibly the response to antiviral therapy. Here, we review the differences in antiviral theraputic response among HBV genotypes and discuss the role of precore or core promoter mutations in response to antiviral therapy.

Early response to lamivudine therapy in clinically non-cirrhotic chronic hepatitis B patients with decompensation

This study aimed to elucidate the rate and predictors of early (6 months) therapeutic responses to lamivudine, the rate of early mortality and the use of the model for end-stage liver disease (MELD) and Index in predicting the survival in patients with a clinical diagnosis of non-cirrhotic chronic hepatitis B with decompensation. Ninety-eight patients with lamivudine therapy were enrolled and MELD and Index scores were calculated. Surviving patients were treated with lamivudine for more than 6 months. Four (4.1%) of the 98 patients died after initiation of lamivudine therapy. After a 6-month lamivudine therapy, 80 (85.1%) patients and 71 (75.5%) patients had normal alanine aminotransferase (ALT) values and negative hepatitis B virus (HBV) DNA (<200 copies/mL), respectively, and hepatitis B e antigen (HBeAg)-negative patients had a significantly higher rate of negative HBV DNA than HBeAg-positive patients (P=0.002). The rates of HBeAg seroconversion and negative HBV DNA were 28.8 and 63.5%, respectively, and patients with HBeAg seroconversion had a significantly higher rate of negative HBV DNA (P=0.004). By multivariate analyses, older age, HBV nongenotype B infection, negative HBeAg and higher ALT levels were factors associated with negative HBV DNA, and a higher ALT level was associated with HBeAg seroconversion at month 6 after lamivudine therapy. MELD score and Index score were significantly associated with death and areas under the receiver operating characteristic curve for predicting survival were 0.936 and 0.907 respectively. We concluded that after 6-month lamivudine therapy, the patients who survived achieved favourable biochemical, virological responses and rate of HBeAg seroconversion. Both MELD and Index scoring systems are good models to predict the 6-month survival.

Comparison of the efficacy of thymosin alpha-1 and interferon alpha in the treatment of chronic hepatitis B: a meta-analysis

Chronic hepatitis B virus (HBV) infection is a serious problem because of its worldwide distribution and possible adverse sequelae, such as cirrhosis and hepatocellular carcinoma. Thymosin alpha-1 (Talpha1) is an immune modifier that has been shown to be effective for chronic hepatitis B (CHB) in some trials. But the trials comparing Talpha1 vs. interferon alpha (IFNalpha) treatment in CHB have been small and the results have been inconsistent. So we conducted a meta-analysis to compare the efficacy of Talpha1 and IFNalpha in the treatment of CHB. Generally, four randomized controlled trials including 199 CHB patients who received Talpha1 or IFNalpha treatment were identified through MEDLINE and EMBASE online search. Virological (for hepatitis B e antigen (HBeAg) positive patients, loss of HBV DNA and HBeAg; for HBeAg negative patients, loss of HBV DNA), biochemical (normalization of transaminases) and complete responses (fulfill criteria of biochemical and virological response simultaneously) were analyzed using the intention-to-treat method. The odds ratio (OR) was used to measure the magnitude of the efficacy. The ORs (95% confidence interval) of the virological response, biochemical response and complete response of Talpha1 over IFNalpha at the end of 6 months treatment were 0.62 (0.35, 1.10), 0.60 (0.34, 1.05) and 0.54 (0.30, 0.97), respectively. The ORs (95% confidence interval) of the virological response, biochemical response and complete response of Talpha1 over IFNalpha at the end of follow-up (6 months post-treatment) were 3.71 (2.05, 6.71), 3.12 (1.74, 5.62) and 2.69 (1.47, 4.91), respectively. These data showed that compared with IFNalpha, the benefit of Talpha1 was not immediately significant at the end of therapy, but virological, biochemical and complete response had a tendency to increase or accumulate gradually after the therapy. For three of the four trials that studied HBeAg-negative patients, the results are mostly applicable to HBeAg-negative CHB.

Genotyping and genomic sequencing in clinical practice

The global prevalence of chronic hepatitis B and its associated serious sequelae demand technologically advanced techniques of management. Nucleic acid testing (NAT) plays a key role in the diagnosis, surveillance, and treatment of chronic hepatitis B. NAT includes quantitative PCR-based HBV DNA assays, HBV genotyping, tests for mutations associated with resistance to antiviral medications, and assays to detect precore and core promoter mutations. This article reviews the uses of NAT in the diagnosis and management of chronic hepatitis B.

Role of viral factors in the natural course and therapy of chronic hepatitis B

Hepatitis B virus (HBV) infection is a global health problem that causes a wide spectrum of liver disease, including acute or fulminant hepatitis, inactive carrier state, chronic hepatitis, cirrhosis, and hepatocellular carcinoma (HCC). The pathogenesis of hepatocyte damage associated with HBV is mainly through immune-mediated mechanisms. On the basis of the virus and host interactions, the natural history of HBV carriers who are infected in early life can be divided into four dynamic phases. The frequency, extent, and severity of hepatitis flares or acute exacerbation in the second immune clearance and/or fourth reactivation phase predict liver disease progression in HBV carriers. In the past decade, hepatitis B viral factors including serum HBV DNA level, genotype, and naturally occurring mutants predictive of clinical outcomes have been identified. The higher the serum HBV DNA level after the immune clearance phase, the higher the incidence of adverse outcomes over time. In addition, high viral load, genotype C, basal core promoter mutation, and pre-S deletion correlate with increased risk of cirrhosis and HCC development. As to the treatment of chronic hepatitis B, patients with high HBV DNA level and genotype C or D infection are shown to have a worse response to interferon therapy. In conclusion, serum HBV DNA level, genotype, and naturally occurring mutants are identified to influence liver disease progression and therapy of chronic hepatitis B. More investigations are needed to clarify the molecular mechanisms of the viral factors involved in the pathogenesis of each stage of liver disease and the response to antiviral treatments.