Clinical course of patients with chronic hepatitis B with viral breakthrough during long-term lamivudine treatment

Research Progress on the Antiviral Activity of Glycyrrhizin and its Derivatives in Liquorice

Liquorice is a traditional medicine. Triterpenoids such as glycyrrhizin and glycyrrhetinic acid are the main active constituents of liquorice. Studies have revealed that these compounds exert inhibitory effects on several viruses, including SARS-CoV-2. The main mechanisms of action of these compounds include inhibition of virus replication, direct inactivation of viruses, inhibition of inflammation mediated by HMGB1/TLR4, inhibition of β-chemokines, reduction in the binding of HMGB1 to DNA to weaken the activity of viruses, and inhibition of reactive oxygen species formation. We herein review the research progress on the antiviral effects of glycyrrhizin and its derivatives. In addition, we emphasise the significance of exploring unknown antiviral mechanisms, structural modifications, and drug combinations in future studies.

A prospective and comparative cohort study on efficacy and drug resistance during long-term lamivudine treatment for various stages of chronic hepatitis B and cirrhosis

BACKGROUND AND AIMS

A prospective, non-randomized cohort study on long-term lamivudine treatment, comparing efficacy, drug resistance, and prognosis for various stages of chronic hepatitis B virus (HBV)-related liver disease was performed to elucidate the significance and indication of lamivudine for individual patients at each stage of disease.

METHODS

A total of 158 cases consisting of 87 chronic hepatitis, 28 compensated cirrhosis, and 43 decompensated cirrhosis, with serum HBV-DNA > 5 log(10) copies/mL and with elevated alanine aminotransferase (ALT) over twice the upper normal limit or complications of hepatic insufficiency, were administered 100 mg of lamivudine daily and monitored for HBV markers, biochemistry, and prognosis.

RESULTS

Lamivudine reduced HBV-DNA and ALT equally in all groups. Serum albumin, prothrombin time (%), and platelet count increased in all groups. The increased margin of albumin was the highest in the decompensated cirrhosis and higher in the compensated cirrhosis than the chronic hepatitis groups. Cumulative incidence of virologic breakthrough was 16%, 42%, 49%, and 53% at 12, 24, 36, and 48 months, respectively, and the strongest predictive factor for lamivudine resistance was persistent HBV-DNA at 3 months. Ascites, encephalopathy, and jaundice improved in the majority of patients with decompensated cirrhosis. On the other hand, hepatic failure developed or deteriorated in 10 patients after virologic breakthrough, and nine of them had decompensated cirrhosis.

CONCLUSIONS

Lamivudine was effective in reducing HBV-DNA and improving hepatic reserve at all stages and was most beneficial and significant for decompensated cirrhosis. Meanwhile, close monitoring of viral load and immediate rescue treatment for lamivudine resistance is necessary to prevent hepatic failure in decompensated cirrhosis.

Entecavir for the treatment of chronic hepatitis B virus infection

OBJECTIVE

This article reviews the pharmacology/pharmacokinetics and therapeutic efficacy of entecavir, which was approved on March 29, 2005, for the management of adult patients with chronic hepatitis B virus (HBV) infection who have active viral replication and/or elevations in liver transaminases or signs of active liver disease on histologic examination. Potential drug interactions and adverse events associated with the use of entecavir are also reviewed.

METHODS

Relevant literature was identified through searches of MEDLINE (1996-July 2005) and BIOSIS (1993-July 2005). Search terms included, but were not limited to, entecavir, BMS-200475, hepatitis B, pharmacology, pharmacokinetics, adverse events, and therapeutic use. Further publications were identified from the reference lists of the identified articles and through correspondence with the manufacturer of entecavir.

RESULTS

Entecavir is highly selective for the HBV and inhibits all 3 steps of viral replication. Results of early studies indicated a 6% resistance potential after 48 weeks of therapy, although the potential may be higher in patients who harbor lamivudine-resistant mutants. The approved dosage in treatment-naive patients is 0.5 mg/d p.o., administered on an empty stomach; in patients who have failed lamivudine therapy or are known to harbor lamivudine-resistant mutants, the approved dosage is 1.0 mg/d p.o.. The oral tablet and solution can be used interchangeably. Entecavir is well absorbed orally, achieving a dose-related Cmax between 0.6 and 1.5 hours after administration. It is metabolized to a small extent and is not a substrate for the cytochrome P450 enzyme system. The mean elimination t(1/2) ranges from 77 to 149 hours in patients with normal kidney function. Entecavir is eliminated primarily in the urine via glomerular filtration and tubular secretion (62%-73%). No dose adjustment appears to be necessary in patients with moderate to severe liver disease alone. The potential for drug interactions with entecavir appears to be minimal, although medications that inhibit tubular secretion of drugs (eg, probenecid) may be expected to prolong serum concentrations of entecavir. One of the Phase III studies of entecavir found statistically significant benefits compared with lamivudine in terms of improvements in liver histology after 48 weeks of therapy (72% vs 62%, respectively; P<0.009), the proportions of patients with undetectable HBV DNA titers on branched DNA signal amplification assay after 48 weeks of therapy (91% vs 65%; P<0.001), and the proportion with undetectable HBV DNA on polymerase chain reaction (PCR) assay after 48 weeks of therapy (69% vs 38%; P<0.001). In another Phase III study, patients who had failed to respond to lamivudine therapy responded to entecavir: after 48 weeks of therapy, significant differences between entecavir and lamivudine were seen in histologic improvement (55% vs 28%; P<0.001) and the proportion of patients with undetectable HBV DNA on PCR assay (21% vs 1%; P<0.001). Adverse events associated with entecavir therapy were similar in character, severity, and incidence to those associated with placebo or lamivudine therapy. The most common adverse events in clinical trials of entecavir were headache (17%-23% of patients), upper respiratory tract infection (18%-20%), cough (12%-15%), nasopharyngitis (9%-14%), fatigue (10%-13%), dizziness (9%), upper abdominal pain (9%-10%), and nausea (6%-8%).

CONCLUSIONS

Entecavir is a new antiviral agent for the management of chronic HBV infection. Questions concerning the ideal length of therapy, long-term efficacy, and resistance rates over time await the results of ongoing clinical trials.