Peginterferon Alfa-2B Dosage

Usual Adult Dose for Chronic Hepatitis C

Combination Therapy: 1.5 mcg/kg subcutaneously once a week

Duration of therapy:
Treatment with peginterferon alfa-2b/ribavirin of interferon alpha-naive patients:

• Genotype 1: 48 weeks
• Genotype 2 and 3: 24 weeks

Retreatment with peginterferon alfa-2b/ribavirin of prior treatment failures: 48 weeks, regardless of HCV genotype

Monotherapy: 1 mcg/kg subcutaneously once a week
Duration of therapy: 1 year

Comments:

• This drug should be used with ribavirin and, if appropriate, an approved HCV NS3/4A protease inhibitor as part of a combination regimen (preferred); combination therapy provides substantially better response rates than monotherapy.
• Ribavirin (capsules or oral solution) dose is 800 to 1400 mg orally per day in 2 divided doses (with food), depending on weight; the manufacturer product information should be consulted.
• The manufacturer product information for the specific HCV NS3/4A protease inhibitor should be consulted for information regarding dosing regimen and administration of the protease inhibitor in combination with peginterferon alfa-2b/ribavirin.
• Patients with previous nonresponse, previous pegylated interferon treatment, significant bridging fibrosis or cirrhosis, and/or genotype 1 infection are less likely to benefit from retreatment after a failing course of therapy.

Use: For the treatment of chronic hepatitis C (CHC) in patients with compensated liver disease

• In combination with ribavirin and an approved HCV NS3/4A protease inhibitor: Indicated in patients with HCV genotype 1 infection
• In combination with ribavirin: Indicated in patients with genotypes other than 1 or in patients with genotype 1 infection where use of an HCV NS3/4A protease inhibitor is not warranted based on tolerability, contraindications, or other clinical factors
• Monotherapy: Indicated in previously untreated patients only; should only be used if there are contraindications to or significant intolerance of ribavirin

Usual Adult Dose for Malignant Melanoma

6 mcg/kg subcutaneously once a week for 8 doses, followed by 3 mcg/kg subcutaneously once a week for up to 5 years

Comments:

• Premedication with 500 to 1000 mg of oral acetaminophen is recommended 30 minutes prior to the first dose and as needed for subsequent doses.

Use: For the adjuvant treatment of melanoma with microscopic or gross nodal involvement within 84 days of definitive surgical resection including complete lymphadenectomy

Usual Pediatric Dose for Chronic Hepatitis C

3 years or older: 60 mcg/m2 subcutaneously once a week

Duration of therapy:

• Genotype 1: 48 weeks
• Genotype 2 and 3: 24 weeks

Comments:

• For use with ribavirin
• Ribavirin (capsules or oral solution) dose is 15 mg/kg orally per day in 2 divided doses (with food); the manufacturer product information should be consulted.
• Patients who reach their 18th birthday while receiving peginterferon alfa-2b/ribavirin should remain on the pediatric dosing regimen.

Use: In combination with ribavirin, for the treatment of CHC in patients with compensated liver disease

Renal Dose Adjustments

Chronic Hepatitis C Patients:
Combination therapy:

• CrCl less than 50 mL/min: Not recommended.

Monotherapy:

• CrCl 30 to 50 mL/min: Dose should be reduced by 25%.
• CrCl 10 to 29 mL/min: Dose should be reduced by 50%.

• If renal function decreases during therapy: Therapy should be discontinued.

Melanoma Patients:

• CrCl 30 to 50 mL/min/1.73 m2: 4.5 mcg/kg subcutaneously once a week for 8 weeks, followed by 2.25 mcg/kg subcutaneously once a week for up to 5 years
• CrCl less than 30 mL/min/1.73 m2: 3 mcg/kg subcutaneously once a week for 8 weeks, followed by 1.5 mcg/kg subcutaneously once a week for up to 5 years

Liver Dose Adjustments

Moderate or severe liver dysfunction in patients treated for viral hepatitis, hepatic decompensation (Child-Pugh B or C [score greater than 6]): Contraindicated

If severe (grade 3) hepatic injury or hepatic decompensation occurs during therapy: Therapy should be discontinued.

Dose Adjustments

CHRONIC HEPATITIS C PATIENTS:
If a serious side effect develops during therapy, the dose of peginterferon alfa-2b and ribavirin should be modified or discontinued until the side effect abates or decreases in severity. If persistent or recurrent serious side effects develop despite adequate dose adjustment, therapy should be discontinued.

Adults:
Combination Therapy: Dose reduction is accomplished in a 2-step process from the original starting dose of 1.5 mcg/kg/week, to 1 mcg/kg/week, then to 0.5 mcg/kg/week, if needed.

Monotherapy: Dose reduction is accomplished by reducing the original starting dose of 1 mcg/kg/week to 0.5 mcg/kg/week.

Based on Depression Severity (DSM-IV):

• Mild: No adjustment recommended.
• Moderate: Initial management (4 to 8 weeks) includes reducing the original starting dose to 1 mcg/kg/week, then to 0.5 mcg/kg/week, if needed, for patients on combination therapy or to 0.5 mcg/kg/week for patients on monotherapy. If symptoms improve and are stable for 4 weeks, recommendations are to continue reduced dosing or return to normal dose.
• Severe: Peginterferon alfa-2b/ribavirin should be permanently discontinued.

Based on Laboratory Parameters:
The original starting dose should be reduced (to 1 mcg/kg/week, then to 0.5 mcg/kg/week, if needed, for patients on combination therapy or to 0.5 mcg/kg/week for patients on monotherapy) if:

• WBC 1 x 10(9)/L to less than 1.5 x 10(9)/L
• Neutrophils 0.5 x 10(9)/L to less than 0.75 x 10(9)/L
• Platelets 25 x 10(9)/L to less than 50 x 10(9)/L

In patients without history of cardiac disease, ribavirin daily dose should be reduced (first dose reduction - by 200 mg/day [or by 400 mg/day if original dose 1400 mg/day]; second dose reduction [if needed] - by an additional 200 mg/day) if:

• Hemoglobin (Hgb) 8.5 to less than 10 g/dL

In patients with history of cardiac disease, peginterferon alfa-2b dose should be reduced by 50% and ribavirin dose should be reduced by 200 mg/day if:

• At least 2 g/dL decrease in Hgb during any 4 week period during therapy

Peginterferon alfa-2b/ribavirin should be discontinued if:

• WBC less than 1 x 10(9)/L
• Neutrophils less than 0.5 x 10(9)/L
• Platelets less than 25 x 10(9)/L
• Hgb less than 8.5 g/dL
• Hgb less than 12 g/dL after 4 weeks of dose reduction (in patients with history of cardiac disease)

Discontinuation of Therapy:

• In HCV genotype 1, interferon alfa-naive patients receiving this drug (alone or with ribavirin) should discontinue therapy if there is not at least a 2 log10 drop or loss of HCV-RNA at 12 weeks of therapy, or if HCV-RNA levels remain detectable after 24 weeks of therapy.
• Regardless of genotype, previously treated patients who have detectable HCV-RNA at Week 12 or 24, are highly unlikely to achieve sustained virologic response and discontinuation of therapy is recommended.
• The manufacturer product information for the specific HCV NS3/4A protease inhibitor should be consulted for information regarding discontinuation based on treatment futility.

Pediatrics:
Dose reduction is accomplished in a 2-step process from the original starting dose of 60 mcg/m2/week, to 40 mcg/m2/week, then to 20 mcg/m2/week, if needed.

Based on Depression Severity:

• Mild: No adjustment recommended.
• Moderate: Initial management (4 to 8 weeks) includes reducing the original starting dose to 40 mcg/m2/week, then to 20 mcg/m2/week, if needed. If symptoms improve and are stable for 4 weeks, recommendations are to continue reduced dosing or return to normal dose.
• Severe: Peginterferon alfa-2b/ribavirin should be permanently discontinued.

Based on Laboratory Parameters:
The original starting dose should be reduced (to 40 mcg/m2/week, then to 20 mcg/m2/week, if needed) if:

• WBC 1 x 10(9)/L to less than 1.5 x 10(9)/L
• Neutrophils 0.5 x 10(9)/L to less than 0.75 x 10(9)/L
• Platelets 50 x 10(9)/L to less than 70 x 10(9)/L

In patients without history of cardiac disease, ribavirin daily dose should be reduced (first dose reduction - to 12 mg/kg/day; second dose reduction - to 8 mg/kg/day) if:

• Hgb 8.5 to less than 10 g/dL

Pediatric patients who have preexisting cardiac conditions should have weekly evaluations and hematology testing if:

• At least 2 g/dL decrease in Hgb during any 4 week period during therapy

Peginterferon alfa-2b/ribavirin should be discontinued if:

• WBC less than 1 x 10(9)/L
• Neutrophils less than 0.5 x 10(9)/L
• Platelets less than 50 x 10(9)/L
• Creatinine greater than 2 mg/dL
• Hgb less than 8.5 g/dL
• Hgb less than 12 g/dL after 4 weeks of dose reduction (in patients with history of cardiac disease)

Discontinuation of Therapy:

• Pediatric patients receiving peginterferon alfa-2b/ribavirin (excluding those with HCV genotype 2 and 3) should discontinue therapy at 12 weeks if their HCV-RNA dropped less than 2 log10 at 12 weeks of therapy compared to pretreatment or at 24 weeks if they have detectable HCV-RNA at 24 weeks of therapy.

MELANOMA PATIENTS:
This drug should be permanently discontinued for:

• Persistent or worsening severe neuropsychiatric disorders
• Grade 4 nonhematologic toxicity
• Inability to tolerate dose of 1 mcg/kg/week
• New or worsening retinopathy

This drug should be withheld if any of the following occurs:

• Absolute neutrophil count (ANC) less than 0.5 x 10(9)/L
• Platelet count less than 50 x 10(9)/L
• ECOG performance status (PS) 2 or greater
• Nonhematologic toxicity grade 3 or greater

This drug may be resumed at a reduced dose when all of the following are present:

• ANC at least 0.5 x 10(9)/L
• Platelet count at least 50 x 10(9)/L
• ECOG PS 0 to 1
• Nonhematologic toxicity has completely resolved or improved to grade 1

Dose modifications when starting dose is 6 mcg/kg/week (Doses 1 to 8):

• First dose reduction: 3 mcg/kg/week
• Second dose reduction: 2 mcg/kg/week
• Third dose reduction: 1 mcg/kg/week
• If unable to tolerate 1 mcg/kg/week: Permanently discontinue.

Dose modifications when starting dose is 3 mcg/kg/week (Doses 9 to 260):

• First dose reduction: 2 mcg/kg/week
• Second dose reduction: 1 mcg/kg/week
• If unable to tolerate 1 mcg/kg/week: Permanently discontinue.

Precautions

US BOXED WARNINGS:
CHRONIC HEPATITIS C PATIENTS:

• RISK OF SERIOUS DISORDERS: Alpha interferons may cause/aggravate fatal or life-threatening neuropsychiatric, autoimmune, ischemic, and infectious disorders. Close monitoring with periodic clinical and laboratory evaluations is recommended. Patients with persistently severe or worsening signs/symptoms of these disorders should be withdrawn from therapy. In most (but not all) cases, these disorders resolve after this drug is stopped.
• RIBAVIRIN-ASSOCIATED EFFECTS: Ribavirin may cause birth defects and fetal death. Extreme care should be taken to avoid pregnancy in female patients and female partners of male patients. Ribavirin causes hemolytic anemia. Anemia associated with ribavirin may worsen cardiac disease.

MELANOMA PATIENTS:

• DEPRESSION AND OTHER NEUROPSYCHIATRIC DISORDERS: Risk of serious depression (with suicidal ideation and completed suicides) and other serious neuropsychiatric disorders increased with alfa interferons. This drug should be permanently discontinued in patients with persistently severe or worsening signs/symptoms of depression, psychosis, or encephalopathy. These disorders may not resolve after therapy is stopped.

Safety and efficacy for treatment of CHC have not been established in patients younger than 3 years. Safety and efficacy for the adjuvant treatment of melanoma have not been established in patients younger than 18 years.

Consult WARNINGS section for additional precautions.

Dialysis

Chronic Hepatitis C Patients:
Combination therapy:

• CrCl less than 50 mL/min: Not recommended.

Monotherapy:

• Hemodialysis: Dose should be reduced by 50%.
• Peritoneal dialysis: Data not available

• If renal function decreases during therapy: Therapy should be discontinued.

Melanoma Patients:

• End-stage renal disease on dialysis: 3 mcg/kg subcutaneously once a week for 8 weeks, followed by 1.5 mcg/kg subcutaneously once a week for up to 5 years

Other Comments

Administration advice:

• Administer dose on the same day of each week and at the same time.
• May minimize the "influenza-like" symptoms associated with administration by using the drug at bedtime and/or by using antipyretics

Storage requirements:

• Prior to reconstitution, single-use prefilled pens should be stored at 2C to 8C (36F to 46F).
• Prior to reconstitution, single-use vials should be stored at 25C (77F); excursions permitted to 15C to 30C (59F to 86F).
• After reconstitution, solution should be used immediately but may be stored up to 24 hours at 2C to 8C (36F to 46F). Do not freeze. Heat should be avoided.

Reconstitution/preparation techniques:

• The manufacturer product information should be consulted.

General:

• For combination therapy: The manufacturer product information for ribavirin and the specific HCV NS3/4A protease inhibitor (if applicable) should be consulted.

Monitoring:

• Cardiovascular: ECG for patients with preexisting cardiac abnormalities (before starting combination therapy)
• Endocrine: Thyroid-stimulating hormone levels (within 4 weeks prior to start of drug, at 3 and 6 months after start, then every 6 months thereafter during therapy)
• General: Blood chemistry testing (before starting therapy and periodically thereafter); HCV-RNA (periodically during therapy); signs/symptoms of interferon toxicity, including elevated serum creatinine
• Hematologic: Hematology testing (before starting therapy and periodically thereafter)
• Hepatic: CHC Patients: Clinical status and hepatic function (during therapy); Melanoma Patients: Hepatic function with serum bilirubin, ALT, AST, alkaline phosphatase, and lactate dehydrogenase (at 2 and 8 weeks, and 2 and 3 months after starting therapy, then every 6 months during therapy)
• Metabolic: Triglyceride levels (periodically)
• Ocular: Eye examination in all patients (at baseline); visual acuity and indirect ophthalmoscopy or fundus photography in patients with preexisting retinopathy; ophthalmologic exams in patients with preexisting ophthalmologic disorders (periodically during therapy)
• Psychiatric: Signs/symptoms of depression and other psychiatric symptoms (during therapy and for at least 6 months after last dose)
• Renal: Renal function in all patients (before starting therapy); signs/symptoms of elevated serum creatinine

Patient advice:

• Keep well hydrated, especially during initial stages of therapy.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

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