Epivir HBV

Epivir HBV (lamivudine) is a prescription antiviral medication specifically formulated for the treatment of chronic hepatitis B virus (HBV) infection in adults and pediatric patients. As an oral nucleoside analog reverse transcriptase inhibitor, it works by inhibiting the replication of HBV DNA, thereby reducing viral load and liver inflammation. Clinical studies demonstrate its efficacy in achieving virological suppression, normalizing ALT levels, and improving liver histology. Proper patient selection and adherence to treatment guidelines are critical for optimizing therapeutic outcomes and managing potential resistance.

Features

• Active ingredient: Lamivudine 100 mg
• Formulation: Film-coated tablets and oral solution (5 mg/mL)
• Mechanism: Nucleoside analog reverse transcriptase inhibitor
• FDA-approved for chronic hepatitis B treatment
• Bioavailability: Approximately 86% for tablets
• Half-life: 5–7 hours in adults with normal renal function

Benefits

• Achieves significant reduction in HBV DNA viral load
• Normalizes serum alanine aminotransferase (ALT) levels
• Demonstrates improvement in liver inflammation and fibrosis scores
• Offers convenient once-daily dosing regimen
• Shows favorable safety profile in clinical trials
• Available in both tablet and liquid formulations for dosing flexibility

Common use

Epivir HBV is indicated for the treatment of chronic hepatitis B virus infection in adults and pediatric patients 2 years of age and older with compensated liver disease and evidence of viral replication. It is typically prescribed for patients with elevated ALT levels and histological evidence of active liver inflammation or fibrosis. Treatment decisions should be based on comprehensive assessment including HBV DNA levels, HBeAg status, liver function tests, and histological findings when available. The medication may be used as monotherapy or in combination regimens per current treatment guidelines.

Dosage and direction

Adults: 100 mg orally once daily, with or without food.
Pediatric patients (2–17 years): 3 mg/kg once daily, up to maximum 100 mg daily.
Renal impairment dosing:

• CrCl 30–49 mL/min: 100 mg first dose, then 50 mg daily
• CrCl 15–29 mL/min: 100 mg first dose, then 25 mg daily
• CrCl 5–14 mL/min: 35 mg first dose, then 15 mg daily
• CrCl <5 mL/min: 35 mg first dose, then 10 mg daily

Treatment duration should be individualized based on virological response, HBeAg seroconversion, and treatment guidelines. Regular monitoring of HBV DNA, ALT, and serological markers is essential throughout therapy.

Precautions

• Monitor for emergence of lamivudine-resistant HBV variants during treatment
• Perform baseline and periodic assessments of renal function
• Evaluate patients for HIV co-infection prior to initiation (lower-dose lamivudine-containing products are inadequate for HIV treatment)
• Monitor for hepatic flares following discontinuation of therapy
• Exercise caution in patients with pre-existing renal impairment
• Assess for possible pancreatitis, particularly in pediatric patients
• Monitor for clinical and laboratory evidence of lactic acidosis

Contraindications

• Hypersensitivity to lamivudine or any component of the formulation
• Use in patients with untreated HIV co-infection (due to potential development of HIV resistance)
• Concurrent administration with other medications containing lamivudine or emtricitabine

Possible side effect

Common (≥10%): Headache, fatigue, nausea, diarrhea, nasopharyngitis
Less common (1–10%): Dizziness, insomnia, cough, abdominal pain, elevated amylase
Rare (<1%): Lactic acidosis, severe hepatomegaly with steatosis, pancreatitis, peripheral neuropathy
Post-marketing reports: Redistribution/accumulation of body fat, hepatic decompensation, Stevens-Johnson syndrome

Drug interaction

• Zidovudine: Increased AUC of zidovudine by approximately 39%
• Trimethoprim/sulfamethoxazole: Increases lamivudine exposure by approximately 40%
• Other nephrotoxic drugs: May require additional monitoring
• Interferon alfa: No significant pharmacokinetic interactions observed
• Ribavirin: Concomitant use may increase risk of mitochondrial toxicity

Missed dose

If a dose is missed, take it as soon as remembered unless it is almost time for the next scheduled dose. Do not double the dose to make up for a missed dose. Maintain regular dosing schedule to ensure consistent antiviral suppression. Document missed doses and discuss patterns of non-adherence with healthcare provider, as inconsistent dosing may contribute to viral resistance.

Overdose

Limited experience with overdose. There is no known antidote for lamivudine overdose. Hemodialysis removes approximately 70% of lamivudine dose over 4 hours, and peritoneal dialysis removes approximately 20% of dose over 12 hours. Treatment should consist of general supportive measures including monitoring of vital signs and observation of clinical status. Consider charcoal slurry if presented within 1 hour of ingestion.

Storage

Store at 25°C (77°F); excursions permitted to 15–30°C (59–86°F). Keep container tightly closed. Protect from moisture. Oral solution: Store at 2–8°C (36–46°F); do not freeze. Use within 30 days after first opening if stored at room temperature, or within 30 days if refrigerated. Keep out of reach of children. Discard any unused medication properly according to local regulations.

Disclaimer

This information is for educational purposes only and does not constitute medical advice. Epivir HBV is available by prescription only and should be used under the supervision of a qualified healthcare professional. Treatment decisions should be based on individual patient characteristics, current treatment guidelines, and thorough risk-benefit assessment. Patients should consult their healthcare provider for personalized medical advice and report any adverse effects promptly.

Reviews

Clinical trials demonstrate that Epivir HBV achieves HBV DNA undetectability in approximately 40-50% of HBeAg-positive patients and 60-70% of HBeAg-negative patients after one year of treatment. Long-term studies show maintained virological suppression in responders, though resistance rates approach 70% after 4 years of monotherapy. Real-world evidence supports its efficacy in achieving virological response and histological improvement, particularly when used according to established treatment guidelines. Patient-reported outcomes indicate generally good tolerability, with treatment continuation rates exceeding 80% in clinical practice.