Entecavir

Entecavir is an antiviral drug against the hepatitis B virus [see Microbiology (12.4) ] .

• Entecavir tablets are indicated for the treatment of chronic hepatitis B virus infection in adults and pediatric patients 2 years of age and older with evidence of active viral replication and either evidence of persistent elevations in serum aminotransferases (ALT or AST) or histologically active disease. Entecavir tablets are a hepatitis B virus nucleoside analogue reverse transcriptase inhibitor indicated for the treatment of chronic hepatitis B virus infection in adults and children at least 2 years of age with evidence of active viral replication and either evidence of persistent elevations in serum aminotransferases (ALT or AST) or histologically active disease.ICD-10: B18.1

• None. None.contraindicated

Nucleoside-inhibitor-treatment-naïve with compensated liver disease (greater than or equal to 16 years old): 0.5 mg once daily. ( 2.2 ) Nucleoside-inhibitor-treatment-naïve and lamivudine-experienced pediatric patients at least 2 years of age and weighing at least 10 kg: dosing is based on weight. ( 2.3 ) Lamivudine-refractory or known lamivudine or telbivudine resistance substitutions (greater than or equal to 16 years old): 1 mg once daily. ( 2.2 ) Decompensated liver disease (adults): 1 mg once daily. ( 2.2 ) Renal impairment: Dosage adjustment is recommended if creatinine clearance is less than 50 mL/min. ( 2.4 ) Entecavir tablets should be administered on an empty stomach. ( 2.1 ) 2.1 Timing of Administration Entecavir tablets should be administered on an empty stomach (at least 2 hours after a meal and 2 hours before the next meal). 2.2 Recommended Dosage in Adults Compensated Liver Disease The recommended dose of entecavir tablets for chronic hepatitis B virus infection in nucleoside-inhibitor-treatment-naïve adults and adolescents 16 years of age and older is 0.5 mg once daily. The recommended dose of entecavir tablets in adults and adolescents (at least 16 years of age) with a history of hepatitis B viremia while receiving lamivudine or known lamivudine or telbivudine resistance substitutions rtM204I/V with or without rtL180M, rtL80I/V, or rtV173L is 1 mg once daily. Decompensated Liver Disease The recommended dose of entecavir tablets for chronic hepatitis B virus infection in adults with decompensated liver disease is 1 mg once daily.

Severe acute exacerbations of hepatitis B virus infection after discontinuation: Monitor hepatic function closely for at least several months. (5.1, 6.1) Co-infection with HIV: Entecavir is not recommended unless the patient is also receiving HAART. (5.2) Lactic acidosis and severe hepatomegaly with steatosis: If suspected, treatment should be suspended. (5.3) 5.1 Severe Acute Exacerbations of Hepatitis B Severe acute exacerbations of hepatitis B have been reported in patients who have discontinued anti-hepatitis B therapy, including entecavir [see Adverse Reactions (6.1) ] . Hepatic function should be monitored closely with both clinical and laboratory follow-up for at least several months in patients who discontinue anti-hepatitis B therapy. If appropriate, initiation of anti-hepatitis B therapy may be warranted. 5.2 Patients Co-infected with HIV and HBV Entecavir has not been evaluated in HIV/HBV co-infected patients who were not simultaneously receiving effective HIV treatment. Limited clinical experience suggests there is a potential for the development of resistance to HIV nucleoside reverse transcriptase inhibitors if entecavir is used to treat chronic hepatitis B virus infection in patients with HIV infection that is not being treated [see Microbiology (12.4) ] . Therefore, therapy with entecavir is not recommended for HIV/HBV co-infected patients who are not also receiving HAART. Before initiating entecavir therapy, HIV antibody testing should be offered to all patients.

The following adverse reactions are discussed in other sections of the labeling: Exacerbations of hepatitis after discontinuation of treatment [see Boxed Warning , Warnings and Precautions (5.1) ] . Lactic acidosis and severe hepatomegaly with steatosis [see Boxed Warning , Warnings and Precautions (5.3) ] . In adults, the most common adverse reactions (≥3%, all severity grades) are headache, fatigue, dizziness, and nausea. The adverse reactions observed in pediatric patients were consistent with those observed in adults. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Amneal Pharmaceuticals at 1-877-835-5472 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch . 6.1 Clinical Trial Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. Clinical Trial Experience in Adults Compensated Liver Disease Assessment of adverse reactions is based on four studies (AI463014, AI463022, AI463026, and AI463027) in which 1,720 subjects with chronic hepatitis B virus infection and compensated liver disease received double-blind treatment with entecavir 0.5 mg/day (n=679), entecavir 1 mg/day (n=183), or lamivudine (n=858) for up to 2 years.

Liver transplant recipients: Limited data on safety and efficacy are available. (8.8) 8.1 Pregnancy Pregnancy Exposure Registry There is a pregnancy exposure registry that monitors pregnancy outcomes in women exposed to entecavir during pregnancy. Healthcare providers are encouraged to register patients by calling the Antiretroviral Pregnancy Registry (APR) at 1-800-258-4263. Risk Summary Prospective pregnancy data from the APR are not sufficient to adequately assess the risk of birth defects, miscarriage or adverse maternal or fetal outcomes. Entecavir use during pregnancy has been evaluated in a limited number of individuals reported to the APR and the number of exposures to entecavir is insufficient to make a risk assessment compared to a reference population. The estimated background rate for major birth defects is 2.7% in the U.S. reference population of the Metropolitan Atlanta Congenital Defects Program (MACDP). The rate of miscarriage is not reported in the APR. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. In the U.S. general population, the estimated background risk of miscarriage in clinically recognized pregnancies is 15% to 20%. In animal reproduction studies, no adverse developmental effects were observed with entecavir at clinically relevant exposures.

Metabolism

The single- and multiple-dose pharmacokinetics of entecavir were evaluated in healthy subjects and subjects with chronic hepatitis B virus infection. Absorption Following oral administration in healthy subjects, entecavir peak plasma concentrations occurred between 0.5 and 1.5 hours.

There is limited experience of entecavir overdosage reported in patients. Healthy subjects who received single entecavir doses up to 40 mg or multiple doses up to 20 mg/day for up to 14 days had no increase in or unexpected adverse events. If overdose occurs, the patient must be monitored for evidence of toxicity, and standard supportive treatment applied as necessary. Following a single 1 mg dose of entecavir, a 4-hour hemodialysis session removed approximately 13% of the entecavir dose.

• Mar 29, 2005NDANDA021798Bristol Myers Squibb
• Mar 29, 2005NDANDA021797Bristol Myers Squibb
• Aug 21, 2015ANDAANDA205740Hetero Labs Ltd V
• Aug 26, 2015ANDAANDA206217Aurobindo Pharma
• Nov 12, 2015ANDAANDA206652Amneal Pharms
• Dec 6, 2016ANDAANDA206872Cipla
• Jun 23, 2017ANDAANDA206745Zydus Pharms
• Oct 10, 2017ANDAANDA208782Prinston Inc

1. 1Death5444.8%
2. 2Off Label Use5154.5%
3. 3Drug Ineffective4363.8%
4. 4Drug Resistance4033.5%
5. 5Diarrhoea3713.3%
6. 6Fatigue3563.1%
7. 7Pyrexia3543.1%
8. 8Hepatitis B3282.9%
9. 9Nausea3192.8%
10. 10Platelet Count Decreased2942.6%
11. 11Pneumonia2942.6%
12. 12Anaemia2312.0%
13. 13Hepatic Failure2292.0%
14. 14Renal Impairment2252.0%
15. 15White Blood Cell Count Decreased2211.9%

The 10 most recently updated of 327 ClinicalTrials.gov registrations naming Entecavir as an intervention. Registration is not evidence of efficacy or safety — reference crosswalk only.

• The Safety and Efficacy of Sequential Treatment of Ropeginterferon Alfa-2b (P1101) and Anti-PD1 in Interferon-Naive Adults With Chronic Hepatitis B or D Infection
  Completed · Phase 1 · Interventional · 20 enrolled · PharmaEssentia
  NCT04638439updated 2026-06-10
• Entecavir Prophylaxis for Hepatitis B Reactivation for CD20 Positive B-cell Lymphoma Patients With Resolved Hepatitis B (Negative Hepatitis B Surface Antigen, Positive Hepatitis B Core Antibody)
  Active not recruiting · Phase 2 · Interventional · 84 enrolled · Sun Yat-sen University
  NCT05453435updated 2026-05-22
• Tenofovir Alafenamide Versus Entecavir for the Treatment of Chronic Hepatitis B
  Recruiting · Phase 4 · Interventional · 140 enrolled · Taichung Veterans General Hospital
  NCT03933384updated 2026-05-14
• ASC22 Combined With Peg-IFNa in Achieving Functional Cure in Patients With Chronic Hepatitis B Virus Infection
  Recruiting · Phase 4 · Interventional · 150 enrolled · The Second Affiliated Hospital of Chongqing Medical University
  NCT07573943updated 2026-05-07
• Chidamide for Maintenance Treatment of HBV-infected Diffuse DLBCL in Patients Initially Treated With R-CHOP
  Recruiting · Phase 3 · Interventional · 200 enrolled · Ou Bai, MD/PHD
  NCT07493109updated 2026-03-25
• Entecavir Resistance-Associated Mutations in Chronic HBV Patients in Turkey (STREAM Study)
  Not yet recruiting · Observational · 700 enrolled · Yaşar Bayındır, MD
  NCT07459426updated 2026-03-09
• Stopping Antiviral Treatment in Chronic Hepatitis B
  Active not recruiting · Observational · 54 enrolled · The University of Hong Kong
  NCT04431245updated 2026-02-10
• A Study to Investigate Safety, Tolerability, Pharmacokinetics, and Pharmacodynamics of RO7565020 in Healthy Participants and in Participants With Chronic Hepatitis B Virus Infection
  Terminated · Phase 1 · Interventional · 60 enrolled · Hoffmann-La Roche
  NCT05763576updated 2026-01-22
• Entecavir With or Without Pegylated Interferon α-2b in Children Aged 3-6 Years With Immune-Tolerant Chronic Hepatitis B
  Not yet recruiting · Phase 4 · Interventional · 80 enrolled · Qing-Lei Zeng
  NCT07345624updated 2026-01-16
• Entecavir With or Without Pegylated Interferon α-2b in Children Aged 3-6 Years With Immune-Active Chronic Hepatitis B
  Not yet recruiting · Phase 4 · Interventional · 60 enrolled · Qing-Lei Zeng
  NCT07345611updated 2026-01-16

Frequently asked questions

How does Entecavir work?

Entecavir is an antiviral drug against the hepatitis B virus [see Microbiology (12.4) ] .

What is Entecavir used for?

According to FDA labeling, Entecavir carries indications including: Entecavir tablets are indicated for the treatment of chronic hepatitis B virus infection in adults and pediatric patients 2 years of age and older with evidence of active viral replication and either evidence of persistent elevations in serum aminotransferases (ALT or AST) or histologically active disease. Entecavir tablets are a hepatitis B virus nucleoside analogue reverse transcriptase inhibitor indicated for the treatment of chronic hepatitis B virus infection in adults and children at least 2 years of age with evidence of active viral replication and either evidence of persistent elevations in serum aminotransferases (ALT or AST) or histologically active disease.. This is a reference summary of labeled uses, not medical advice or a treatment recommendation.

What class of drug is Entecavir?

Entecavir is classified as Nucleoside and nucleotide reverse transcriptase inhibitors, Nucleoside Reverse Transcriptase Inhibitors.

What are the brand names for Entecavir?

Entecavir is marketed under brand names including Baraclude.

What are the contraindications for Entecavir?

Entecavir labeling lists contraindications including: None. None.. Always consult the full prescribing information and a clinician.