Recommended Dose of Peginterferon alfa-2b (Fondared)
The recommended dose of Peginterferon alfa-2b (Fondared) is 1.5 μg/kg administered subcutaneously once weekly for patients with normal renal function. 1
Dosing Based on Renal Function
- For patients with normal renal function, the standard dose of 1.5 μg/kg subcutaneously once weekly is recommended 1, 2
- For patients with moderate renal impairment (creatinine clearance 30-50 mL/min), the dose should be decreased by 25% 1
- For patients with severe renal impairment (creatinine clearance 10-29 mL/min) or on hemodialysis, the dose should be decreased by 50% 1
Treatment Duration
The duration of treatment varies based on the condition being treated:
- For HBeAg-positive chronic hepatitis B: 48 weeks of treatment is recommended 1, 3
- For HBeAg-negative chronic hepatitis B: 48 weeks of treatment is recommended 1
- For chronic hepatitis C: 48 weeks of treatment is typically recommended, though this may vary by genotype 2
Special Populations
HIV Co-infection
- In HIV/HCV co-infected patients, the same dose of peginterferon alfa-2b (1.5 μg/kg/week) can be used as recommended for HCV monoinfection 1, 4
- Treatment outcomes are generally better with peginterferon alfa-2b compared to standard interferon in HIV co-infected patients (27% vs 20% sustained virologic response) 4
Pediatric Patients
- Peginterferon alfa-2b has not been approved for treatment of chronic hepatitis B in children 1
- For hepatitis C in children, dosing should be based on body surface area calculations 5
Monitoring and Dose Adjustments
- Regular monitoring of complete blood counts and liver function tests is essential during treatment 5
- Dose modifications may be required based on laboratory abnormalities or adverse events 5
- For patients with severe renal impairment, more frequent monitoring is recommended due to increased risk of toxicity 5
Common Pitfalls and Considerations
- Peginterferon alfa-2b should be used with caution in patients with decompensated liver disease due to risk of hepatic decompensation 1
- In patients with cirrhosis, close monitoring is essential as interferon-related flares of hepatitis may precipitate hepatic decompensation 1
- When used in combination with ribavirin, be aware that ribavirin dosing may need to be adjusted separately based on renal function 1
- Extended interval dosing (such as every 48 hours) is not recommended for peginterferon alfa-2b, unlike some other anticoagulants like fondaparinux 6
Remember that peginterferon alfa-2b has largely been replaced by newer direct-acting antivirals for hepatitis C treatment in many clinical settings, but it remains an important option for certain patient populations, particularly those with hepatitis B.