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interferon alfa 2b (Rx)Brand and Other Names:Intron A, Interferon alfa-2b

 
 
 

Dosing & Uses

AdultPediatric

Dosage Forms & Strengths

injectable solution

  • 6 million International Units/mL (3.8mL vial)
  • 10 million International Units/mL (3.2mL vial)

multidose pen; 6 doses each

  • 22.5 million International Units/1.5mL
  • 37.5 million International Units/1.5mL
  • 75 million International Units/1.5mL

powder for injection

  • 10 million International Units/vial
  • 18 million International Units/vial
  • 50 million International Units/vial
more...

Hairy Cell Leukemia

2 million Units/m² IM/SC 3 times/wk for up to 6 mo 

If severe adverse reaction (ADR) develop: reduce dose by 50% or temporarily withhold, THEN

Resume at 50% after ADRs abate: 1 million Units/m² IM/SC 3 times/wk

If severe ADRs persist discontinue permanently

Discontinue Intron A for progressive disease or failure to respond after 6 mo of treatment

Malignant Melanoma

Induction 20 million Units/m² IV over 20 min, 5 days/wk for 4 wk 

Maintenance dose: 10 million Units/m² SC 3 times/wk for 48 wk

Withhold treatment if ANC <500/mm³ or ALT/AST >5 times upper limit of normal (ULN); re-start at 50% previous dose

Permanently discontinue if the following is observed

  • Toxicity does not abate after withholding
  • Severe ADRs recur in patients receiving reduced doses
  • ANC <250/mm³ or ALT/AST >10x ULN

Follicular Lymphoma

5 million units 3 times/week for up to 18 mo in conjunction with anthracycline-containing combination chemotherapy in patients >18 years old

See Mfr's prescribing packet for additional chemo dosing information

Condylomata Acuminata

1 million units injected into each lesion 3 times/week qODay for 3week

May repeat course if unsatisfactory results 12-16 wk after initial treatment

Max 5 lesions/single course of treatment

Do not use the 18 or 50 million Units powder for injection

Do not use the 18 million Units multidose Intron A solution for injection

Do not use multidose pens

AIDS-related Kaposi's Sarcoma

30 million Units/m² IM/SC 3 times/wk for 16 wk 

Dose reduction frequently required: See Mfr's PI

Chronic Hepatitis C

3 million units IM/SC 3 times/wk for16 wk

If ALT normalized after 16 wk, continue treatment for 18-24 mo

If ALT not normalized or high levels of HCV RNA after 16 wk, consider discontinuing treatment

Acute Hepatitis C

5 million Units SC/IM qd for 4 wk, then 3 times/wk for 20 wk

If severe adverse reactions develop reduce dose by 50% or temporarily withhold until adverse reactions abate

If intolerance persists discontinue permanently

Chronic Hepatitis B

30-35 million Units SC/IM per wk, either as 5 million Units qDay or 10 millon Units 3 times/wk for 16 wk

Reduce 50%: WBC <1.5 x 10^9/L; Granulocyte <0.75 x 10^9/L; platelets <50 x 10^9/L

Discontinue permanently: WBC < 1.0 x 10^9/L; Granulocyte <0.5 x 10^9/L; platelet < 25 x 10^9/L

If severe adverse reactions develop reduce dose by 50% or temporarily withhold until adverse reaction abate

If intolerance persists discontinue permanently

Other Information

Monitor: LFTs, CBC, platelets, Hgb, Electrolytes, TSH

See also combo with ribavirin

Dosage Forms & Strengths

injectable solution

  • 6 million International Units/mL (3.8mL vial)
  • 10 million International Units/mL (3.2mL vial)

multidose pen; 6 doses each

  • 22.5 million International Units/1.5mL
  • 37.5 million International Units/1.5mL
  • 75 million International Units/1.5mL

powder for injection

  • 10 million International Units/vial
  • 18 million International Units/vial
  • 50 million International Units/vial
more...

Chronic Hepatitis B

3 million Units/m² IM/SC 3 times/wk for 1 wk; increase to 6 million U/m² 3 times/wk SC for 16-24 wk; not to exceed 10 million Units/dose 3 times/wk 

Dose adjustments: See manufacturer's package insert

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Interactions

Interaction Checker

interferon alfa 2b and

No Results

     
     activity indicator 
    No Interactions Found
    Interactions Found

    Contraindicated

      Serious - Use Alternative

        Significant - Monitor Closely

          Minor

            Sort by :  
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            Adverse Effects

            >10%

            Fatigue (8-96%)

            Fever (34-94%)

            Neutropenia (92%)

            Flu-like syndrome (79%)

            Myalgia (28-75%)

            Anorexia (1-69%)

            Leukopenia (68%)

            Nausea (17-66%)

            Transaminases increased (13-63%)

            Weakness (63%)

            Headache (21-62%)

            Chills (54%)

            Diarrhea (2-45%)

            Rigors (42%)

            Depression (up to 40% of pts), suicidal ideation/ attempts, suicide

            Alopecia (38%)

            Dyspnea (34%)

            Somnolence (33%)

            Vomiting (2-32%)

            Anemia (32%)

            Cough (31%)

            Pharyngitis (31%)

            Chest pain (28%)

            Xerostomia (28%)

            Rash (25%)

            Dizziness (24%)

            Taste alteration (24%)

            Abdominal pain (1-23%)

            Irritability (22%)

            Sinusitis (21%)

            Skeletal pain (21%)

            Diaphoresisi (1-21%)

            Paresthesias (1-21%)

            Arthralgia/back pain (19%)

            Pain (18%)

            Moniliasis (17%)

            Thrombocytopenia (15%)

            Amnesia (14%)

            Constipation (14%)

            Gingivitis (14%)

            Impaired concentration (14%)

            Malaise (14%)

            Weight loss (1-13%)

            Amenorrhea (12%)

            BUN increased (12%)

            Confusion (12%)

            Insomnia (12%)

            Iruritus (11%)

            1-10%

            Bronchitis (10%)

            Dry skin (10%)

            Edema (10%)

            Hypoestheisa (10%)

            Loose stools (10%)

            Nasal congestion (10%)

            Polyuria (10%)

            Anxiety (9%)

            Hypertension (9%)

            Dermatitis (8%)

            Dyspepsia (8%)

            Vertigo (8%)

            Agitation (7%)

            Infection (7%)

            SCr increased (6%)

            Herpes virus infections (5%)

            UTI (5%)

            <1%

            Acute hypersensitivity reactions; exacerbation of preexisting psoriasis & sarcoidosis

            Myelosuppression, thyroid dysfunction, hepatotox., pulmonary infiltrates, retinal hemorrhage

            Severe cytopenias incl aplastic anemia

            Autoimmune dz, DM/hyperglycemia (rare)

            Posmarketing reports

            Pulmonary fibrosis

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            Warnings

            Black Box Warnings

            Alfa interferons cause or aggravate fatal or life-threatening neuropsychiatric, autoimmune, ischemic, and infectious disorders

            The risk of serious depression, with suicidal ideation and completed suicides, and other serious neuropsychiatric disorders are increased with alpha interferons

            Discontinue drug if persistently severe or worsening signs or symptoms of the above conditions are present; disorders typically resolve after stopping therapy

            These disorders may not resolve after the drug is discontinued

            Monitored closely with periodic clinical and laboratory evaluations

            Combination therapy with ribavirin

            • Ribavirin may cause birth defects and/or fetal death
            • Extreme care must be taken to avoid pregnancy in women taking peginterferon alfa-2a and in female partners of men taking peginterferon alfa-2a
            • Ribavirin causes hemolytic anemia; associated anemia may result in worsening of cardiac disease
            • Because ribavirin is genotoxic and mutagenic, consider it a potential carcinogen

            Contraindications

            Hypersensitivity

            Autoimmune hepatitis

            Decompensated liver disease (Child-Pugh >6 [class B and C])

            Contraindications for combination therapy with ribavirin:

            • Pregnant women and men whose female partners are pregnant.
            • Hemoglobinopathies (e.g., thalassemia major, sickle-cell anemia)
            • Creatinine clearance less than 50 mL/min

            Cautions

            Life-threatening or fatal neuropsychiatric events, including suicide, suicidal and homicidal ideation, depression, relapse of drug addiction/overdose, and aggressive behavior sometimes directed towards others reported in patients with and without a previous psychiatric disorder during therapy and follow-up; psychoses, hallucinations, bipolar disorders, and mania have been observed in patients treated with interferon alpha should be used with caution in patients with a history of psychiatric disorders; discontinue if severe depression develops

            If psychiatric symptoms persist or worsen, or suicidal or homicidal ideation or aggressive behavior towards others identified, discontinue therapy and follow patient closely, with psychiatric intervention as appropriate; narcotics, hypnotics, or sedatives may be used concurrently with caution and patients should be closely monitored until adverse effects resolved

            Dyspnea, pulmonary infiltrates, pneumonia, bronchiolitis obliterans, interstitial pneumonitis, pulmonary hypertension, and sarcoidosis, some resulting in respiratory failure or patient deaths, may be induced or aggravated by therapy; recurrence of respiratory failure has been observed with interferon rechallenge; monitor

            Development or exacerbation of autoimmune disorders (e.g., thyroiditis, thrombotic thrombocytopenic purpura, idiopathic thrombocytopenic purpura, rheumatoid arthritis, interstitial nephritis, systemic lupus erythematosus, and psoriasis) observed; use with caution in patients with autoimmune disorders

            Caution in pre-existing cardiac abnormalities &/or advanced cancer Ischemic and hemorrhagic cerebrovascular events reported

            Pancreatitis and ulcerative or hemorrhagic/iscemic colitis may occur

            Severe decreases in neutrophil or platelet counts reported

            Hepatitis C (CHC) patients with cirrhosis may be at risk of hepatic decompensation and death when treated with alpha interferons, including peginterferon alpha 2b; cirrhotic CHC patients co-infected with HIV receiving highly active antiretroviral therapy (HAART) and alpha interferons with or without ribavirin appear to be at increased risk for development of hepatic decompensation compared to patients not receiving HAART; monitor clinical status and hepatic function during treatment and discontinue immediately if decompensation (Child-Pugh score greater than 6) observed

            Monitor patients with impaired renal function, for signs and symptoms of interferon toxicity, including increases in serum creatinine; adjust dose or discontinue therapy accordingly

            Serious, acute hypersensitivity reactions and cutaneous eruptions reported

            Dental/periodontal disorders reported with combination therapy Hypertriglyceridemia may result in pancreatitis (e.g., triglycerides greater than 1000 mg/dL)

            Weight loss and growth inhibition reported during combination therapy in pediatric patients

            Long-term growth inhibition (height) reported in some patients

            Peripheral neuropathy observed when used in combination with telbivudine

            Risk of visual impairment and retinal disorders; discontinue if ophthalmologic problems develop

            Use with caution in patients with endocrine disorder: thyroid disease; DM prone to ketoacidosis

            Pre-existing cardiac abnormalities &/or advanced cancer

            AIDS-related Kaposi's Sarcoma: do not use in patients w/ rapidly progressive disease

            Discontinue if acute hypersensitivity occurs

            Risk of exacerbation of preexisting psoriasis & sarcoidosis; risk of developing new sarcoidosis

            Patients should be well hydrated during initial treatment

            If platelets <50,000/mm³, do not administer IM (may admin SC)

            Do not use the 18 million IU or 50 million IU powder for injection or the18 million IU multidose vial for condylomata acuminata

            Increases risk of hepatic decompensation and death in patients with cirrhosis; any patient developing liver function abnormalities during treatment should be monitored closely and if appropriate, treatment should be discontinued

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            Pregnancy & Lactation

            Pregnancy Category: C

            Lactation: unknown

            Pregnancy Categories

            A:Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.

            B:May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.

            C:Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.

            D:Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.

            X:Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.

            NA:Information not available.

            more...
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            Pharmacology

            Mechanism of Action

            Inhibits HBV replication; immunomodulatory actions; may induce gene transcription; interferes with oncogene expression, may change cell surface antigen expressoin; cytotoxic activity of macrophages increases

            Suppresses cell proliferation

            Pharmacokinetics

            Half-Life: 2-3 hr (IM/SC); 2 hr (IV)

            Peak Plasma Time: 3-12 hr (IM/SC); 30 min (IV)

            Pharmacogenomics

            Polymorphic cytokine genes (encoding IL-10, a Th2 cytokine); Th2 responses are associated with production of large amounts of antibodies

            Patients with chronic hepatitis C are 5 times more likely to have a favorable response to interferon alfa if they carried the IL-10 genetic polymorphism that results in low expression of IL-10 than if they did not

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            Administration

            IV Preparation

            General

            • Reconstitute vials with provided diluent
            • Preparation should be clear & colorless to light yellow

            IM, SC, or Intralesional Preparation

            • Inject 1 mL diluent (SWI, supplied) into drug vial
            • Swirl gently to dissolve powder
            • Withdraw appropriate dose to be injected
            • Refer to Medication Guide for detailed instructions

            IV Administration

            • Prepare immediately prior to use
            • Reconstitute w/ diluent provided
            • Inject 1 mL diluent (SWI, supplied) into drug vial
            • Swirl gently to dissolve powder
            • Withdraw appropriate dose & inject into a 100 mL bag of NS
            • Make sure final conc of Intron A is NOT <10 MIU/100 mL
            • Refer to Medication Guide for detailed instructions

            Intron A Solution for Injection not recommended for IV

            SC Administration

            SC administration is suggested for those who are at risk for bleeding or thrombocytopenic

            Rotate SC injection site

            Storage

            Refrigerate intact vials

            Powder & premixed solutions are stable at room temp for 7 d & for 30 d if refrigerated

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            Images

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            Formulary

            FormularyPatient Discounts

            To view formulary information first create a list of plans. Your list will be saved and can be edited at any time.

            Adding plans allows you to:

            • View the formulary and any restrictions for each plan.
            • Manage and view all your plans together – even plans in different states.
            • Compare formulary status to other drugs in the same class.
            • Access your plan list on any device – mobile or desktop.

            The above information is provided for general informational and educational purposes only. Individual plans may vary and formulary information changes. Contact the applicable plan provider for the most current information.

            Tier Description
            1 This drug is available at the lowest co-pay. Most commonly, these are generic drugs.
            2 This drug is available at a middle level co-pay. Most commonly, these are "preferred" (on formulary) brand drugs.
            3 This drug is available at a higher level co-pay. Most commonly, these are "non-preferred" brand drugs.
            4 This drug is available at a higher level co-pay. Most commonly, these are "non-preferred" brand drugs or specialty prescription products.
            5 This drug is available at a higher level co-pay. Most commonly, these are "non-preferred" brand drugs or specialty prescription products.
            6 This drug is available at a higher level co-pay. Most commonly, these are "non-preferred" brand drugs or specialty prescription products.
            NC NOT COVERED – Drugs that are not covered by the plan.
            Code Definition
            PA Prior Authorization
            Drugs that require prior authorization. This restriction requires that specific clinical criteria be met prior to the approval of the prescription.
            QL Quantity Limits
            Drugs that have quantity limits associated with each prescription. This restriction typically limits the quantity of the drug that will be covered.
            ST Step Therapy
            Drugs that have step therapy associated with each prescription. This restriction typically requires that certain criteria be met prior to approval for the prescription.
            OR Other Restrictions
            Drugs that have restrictions other than prior authorization, quantity limits, and step therapy associated with each prescription.
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            Select a class to view formulary status for similar drugs

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