What is the recommended dose of tenofovir (TDF) for the treatment of hepatitis B?

Recommended Dose of Tenofovir (TDF) for Hepatitis B Treatment

The recommended dose of tenofovir disoproxil fumarate (TDF) for the treatment of chronic hepatitis B in adults is 300 mg once daily taken orally without regard to food. 1

Dosing Guidelines by Age Group

Adults and Adolescents ≥12 years (≥35 kg)

• Standard dose: 300 mg once daily 1
• No dosage adjustment needed for patients with liver disease 2

Children and Adolescents (12 to <18 years)

• Dose: 8 mg/kg daily (up to maximum 300 mg) 3
• Approved for use in persons older than 12 years 3

Dosage Adjustments for Renal Impairment in Adults

Tenofovir is eliminated primarily through renal excretion, including tubular secretion, requiring dose adjustments in patients with renal dysfunction 2:

• Normal renal function: 300 mg once daily
• Creatinine clearance 30-49 mL/min: 300 mg every 48 hours
• Creatinine clearance 10-29 mL/min: 300 mg every 72-96 hours
• Hemodialysis patients: 300 mg every 7 days or after approximately 12 hours of dialysis 1

Clinical Efficacy

Tenofovir DF has demonstrated high efficacy in treating chronic hepatitis B:

• In HBeAg-positive patients: 76% achieved undetectable HBV DNA (<400 copies/mL) after 48 weeks 3
• In HBeAg-negative patients: 93% achieved undetectable HBV DNA after 48 weeks 3
• Long-term studies show sustained viral suppression rates of 97-99% after 5-8 years of treatment 3
• No resistance to tenofovir has been detected in treatment-naïve patients after up to 8 years of therapy 3

Monitoring Recommendations

• Baseline assessment: Creatinine clearance, serum phosphorus
• During treatment: Monitor renal function and serum phosphorus every 3 months in patients at risk for renal dysfunction 3
• Monitor HBV DNA levels at 12 weeks to identify primary treatment failure and at 24 weeks to confirm continued virologic suppression 3

Important Clinical Considerations

• Tenofovir should not be used with other tenofovir-containing products or adefovir (HEPSERA) 1
• Severe acute exacerbations of hepatitis B can occur upon discontinuation of therapy; hepatic function should be closely monitored if treatment is stopped 1
• Tenofovir has shown efficacy against both wild-type and lamivudine-resistant HBV 4
• The newer formulation, tenofovir alafenamide (TAF), is available at a lower dose (25 mg daily) with similar efficacy but improved renal and bone safety profile compared to TDF 5, 6

Pitfalls and Caveats

• Primary non-response to tenofovir is rare; patients who do not respond after 12-24 weeks should be evaluated for compliance 3
• Long-term use of tenofovir may be associated with renal toxicity and decreased bone mineral density, though at lower rates than previously used agents 3
• Patients with inadequate virologic response after 48 weeks of therapy may continue treatment if HBV DNA levels are declining, as response rates increase over time 3
• Abrupt discontinuation can lead to severe hepatitis flares; close monitoring is essential if treatment must be stopped 1

Tenofovir DF remains one of the first-line agents for chronic hepatitis B treatment due to its potent antiviral activity, high barrier to resistance, and favorable long-term efficacy profile.