Entecavir

This article examines the use of Entecavir, a potent antiviral medication, in clinical trials for the treatment of chronic hepatitis B. Entecavir has shown promise in suppressing hepatitis B virus (HBV) replication and improving liver function in patients with chronic HBV infection. We’ll explore various studies investigating Entecavir’s efficacy, safety, and potential combinations with other treatments.

Table of Contents

What is Entecavir?

Entecavir is a medication used to treat chronic hepatitis B virus (HBV) infection. It belongs to a class of drugs called nucleoside analogues, which work by interfering with the virus’s ability to replicate. Entecavir is also known by its brand names Baraclude and BMS-200475[1][2].

What Conditions Does Entecavir Treat?

Entecavir is primarily used to treat chronic hepatitis B, a viral infection that affects the liver. This condition can lead to serious liver problems if left untreated, including cirrhosis (scarring of the liver) and liver cancer[3]. Entecavir is effective in treating both HBeAg-positive and HBeAg-negative chronic hepatitis B patients. HBeAg (Hepatitis B e Antigen) is a protein produced by the hepatitis B virus, and its presence or absence in the blood can indicate different stages of the infection[4].

How Entecavir Works

Entecavir works by inhibiting the replication of the hepatitis B virus. It does this by interfering with the viral DNA polymerase, an enzyme that the virus needs to make copies of itself. By reducing the amount of virus in the body, Entecavir helps to decrease liver inflammation and improve liver function[5].

Dosage and Administration

Entecavir is typically taken as a tablet by mouth. The usual dosage is 0.5 mg or 1 mg once daily, depending on the patient’s specific condition and previous treatment history. It’s important to take Entecavir exactly as prescribed by your doctor[6]. The duration of treatment can vary, but it often continues for several months or even years, as determined by your healthcare provider.

Effectiveness of Entecavir

Clinical trials have shown that Entecavir is highly effective in treating chronic hepatitis B. It can significantly reduce the levels of HBV DNA in the blood, which is a measure of the amount of virus present. Many patients achieve undetectable levels of HBV DNA after treatment with Entecavir[5]. Other markers of effectiveness include:

  • ALT normalization: ALT (Alanine Aminotransferase) is a liver enzyme that can indicate liver damage when elevated. Entecavir treatment often leads to normalization of ALT levels[1].
  • HBeAg loss and seroconversion: In HBeAg-positive patients, Entecavir can lead to the loss of HBeAg and the development of antibodies against it (seroconversion), which is a sign of improved immune control over the virus[2].
  • HBsAg loss: In some cases, treatment can lead to the loss of HBsAg (Hepatitis B surface Antigen), which is considered a functional cure for hepatitis B[5].

Side Effects and Safety

Entecavir is generally well-tolerated, but like all medications, it can cause side effects. Common side effects may include headache, fatigue, dizziness, and nausea. More serious side effects are rare but can include lactic acidosis (a buildup of lactic acid in the body) and severe liver problems[1]. It’s important to note that stopping Entecavir suddenly can cause a flare-up of hepatitis B. Therefore, you should never stop taking this medication without consulting your doctor[7].

Entecavir in Combination Therapy

Some studies have explored the use of Entecavir in combination with other antiviral medications. For example, a study compared the combination of Entecavir and Tenofovir (another antiviral drug) to Entecavir alone. While both treatments were effective, the combination therapy showed some potential benefits in certain patient groups[5].

Special Considerations

Entecavir may be used in specific situations beyond standard chronic hepatitis B treatment:

  • Hepatitis B reactivation prevention: In patients with a history of hepatitis B who are undergoing chemotherapy for cancer, Entecavir may be used to prevent reactivation of the virus. This is particularly important in colorectal cancer patients who are inactive hepatitis B carriers[8].
  • Tuberculosis treatment: In patients with both tuberculosis and hepatitis B, Entecavir may be used to reduce the risk of hepatitis flares during anti-tuberculosis treatment[7].
Always inform your healthcare provider about all your medical conditions and medications to ensure the safe and effective use of Entecavir.

Aspect Details
Primary Use Treatment of chronic hepatitis B virus (HBV) infection
Mechanism of Action Inhibits HBV replication by targeting viral DNA polymerase
Efficacy High rates of HBV DNA suppression (up to 96% in some trials)
Safety Profile Generally well-tolerated with few serious adverse events reported
Dosage Typically 0.5 mg or 1.0 mg once daily, depending on patient factors
Treatment Duration Varies, but often 48-96 weeks in clinical trials; some patients may require longer treatment
Combination Therapies Studied with Tenofovir, Resveratrol, and other antivirals
Special Populations Investigated in treatment-naïve patients, those with suboptimal response to other antivirals, and as prophylaxis in certain scenarios

Ongoing Clinical Trials on Entecavir

  • Study on the Effects and Safety of Ianalumab in Adults with Lupus Nephritis Who Completed Previous Treatment

    Recruiting

    1 1 1 1
    Investigated diseases:
    Czechia France Hungary Romania Spain
  • Study on the Effectiveness and Safety of Ianalumab for Patients with Diffuse Cutaneous Systemic Sclerosis

    Recruiting

    1 1
    Austria Belgium France Germany Greece Hungary +4
  • Study on Long-Term Safety of Ianalumab for Patients with Systemic Lupus Erythematosus

    Recruiting

    1 1 1
    Bulgaria Czechia France Germany Hungary Italy +5
  • Study on the Effects and Safety of Bulevirtide, Peginterferon Alfa-2a, and Entecavir in Patients with Chronic Hepatitis D

    Recruiting

    1 1 1 1
    Sweden
  • Study of ianalumab for adults with primary immune thrombocytopenia or warm-antibody autoimmune hemolytic anemia who previously responded to ianalumab

    Not yet recruiting

    1 1 1
    Belgium Bulgaria Czechia France Germany Hungary +3
  • Phase 3 study of ianalumab plus standard drug combination in adults and adolescents with systemic lupus erythematosus

    Not recruiting

    1 1 1
    Bulgaria Czechia Hungary Poland Portugal Slovakia +1
  • A Study of Ianalumab and Eltrombopag for Patients with Primary Immune Thrombocytopenia Who Did Not Respond Well to or Relapsed After Steroid Treatment

    Not recruiting

    1 1 1
    Austria Belgium Czechia France Germany Hungary +5
  • Study on the Effects of Ianalumab in Patients with Sjögren’s Syndrome

    Not recruiting

    1 1 1
    Investigated diseases:
    France
  • Study on Stopping Tenofovir Alafenamide, Tenofovir Disoproxil, and Entecavir in Patients with Chronic Hepatitis B

    Not recruiting

    1 1 1
    Investigated diseases:
    Belgium
  • Study on the Effects of Ianalumab with Standard Therapy for Patients with Active Lupus Nephritis

    Not recruiting

    1 1 1
    Investigated diseases:
    Czechia Estonia France Germany Hungary Italy +3

Glossary

  • Hepatitis B virus (HBV): A viral infection that attacks the liver and can cause both acute and chronic disease. It is transmitted through contact with blood or other body fluids of an infected person.
  • Entecavir: An antiviral medication used to treat chronic hepatitis B. It works by stopping the hepatitis B virus from multiplying in the body.
  • HBV DNA: The genetic material of the hepatitis B virus. Measuring HBV DNA levels in the blood helps to determine the amount of virus present and monitor treatment effectiveness.
  • HBeAg: Hepatitis B e antigen, a protein produced by the hepatitis B virus. Its presence in the blood indicates that the virus is actively replicating.
  • ALT (Alanine aminotransferase): An enzyme found primarily in the liver. Elevated levels in the blood can indicate liver damage or inflammation.
  • Seroconversion: The development of detectable antibodies in the blood that are directed against an infectious agent, such as the hepatitis B virus.
  • Virologic breakthrough: An increase in viral load (usually HBV DNA) of at least 1 log10 (10-fold) above the lowest level achieved during treatment.
  • cccDNA: Covalently closed circular DNA, a form of the hepatitis B virus genome that persists in the nucleus of infected liver cells and serves as a template for viral replication.

References

  1. https://clinicaltrials.gov/study/NCT00718887
  2. https://clinicaltrials.gov/study/NCT01037062
  3. https://clinicaltrials.gov/study/NCT01711567
  4. https://clinicaltrials.gov/study/NCT02523547
  5. https://clinicaltrials.gov/study/NCT00410072
  6. https://clinicaltrials.gov/study/NCT00975091
  7. https://clinicaltrials.gov/study/NCT01724723
  8. https://clinicaltrials.gov/study/NCT02777814