Interferon-α

Administration

• Type: Antiviral, antineoplastic
• Dosage Forms:
• Routes of Administration: Injection
• Common Trade Names:

Adult Dosing

• Variable depending on indication and formulation (interferon-α₂A, -α₂B, -αn3, -alfacon, peginterferon α-2a, peginterferon α-2b)
• Used to treat:
  • Chronic hepatitis B, chronic hepatitis C
  • Polycythemia vera, essential thrombocytopenia
  • Condyloma acuminatum (refractory/recurrent)
  • Kaposi's sarcoma, Malignant melanoma (adjunct)
  • Carcinoid tumor
  • Multiple myeloma, hairy cell leukemia, follicular lymphoma, chronic myelogenous leukemia (Philadelphia chromosome positive)
  • Metastatic renal cell carcinoma

Pediatric Dosing

• Variable depending on indication and formulation (interferon-α₂A, -α₂B, -αn1, -αn3, -alfacon)
• Used to treat:
  • chronic myelogenous leukemia (Philadelphia chromosome positive)
  • Chronic hepatitis B, chronic hepatitis C
  • Papillomatosis (adjunct)

Special Populations

• Pregnancy Rating: C. When used with ribavirin, may lead to fetal defects or fetal death
• Lactation risk: Infant risk cannot be ruled out
• Renal dosing: IFN-α₂B and pegylated IFN-α₂B contraindicated if CrCl <50
• Hepatic dosing: contraindicated in decompensated liver disease

Contraindications

• Allergy to class/drug or inactive ingredients: may contain benzyl peroxide, bovine/ovine Ig, mouse IgG, polymyxin B, neomycin, egg protein
• Autoimmune hepatitis
• Decompensated liver disease
• Hemoglobinopathies (e.g. thalassemia major, sickle cell) when used with ribavirin
• Pregnancy or men with pregnant female partners (in combination with ribavirin)

Adverse Reactions

Serious

• Dysrhythmia, hypotension, cardiomyopathy, MI
• Raynaud's disease, vasculitis
• Diabetes, hypertriglyceridemia, decreased body growth
• GI bleed, ischemic colitis
• Pancreatitis
• Anemia, aplastic anemia, thrombocytopenia, lymphocytopenia, neutropenia
• TTP
• Hepatotoxicity
• Autoimmune disease, lupus
• Rhabdomyolysis, myositis
• Stroke, cerebral hemorrhage, coma, encephalopathy
• Seizure
• Visual loss, optic neuritis, retinal hemorrhage, retinal artery/vein thrombosis
• Suicidal ideation/behavior, depression, psychotic disorder, agressive behavior
• Obliterative bronchiolitis, pneumonitis, pneumothorax, PE, pulmonary hypertension, sarcoidosis
• Erythroderma, Stevens-Johnson syndrome
• Infection

Common

• Alopecia
• Dermatitis, pruritus, dry skin, injection site reaction
• Weight loss
• Nausea/vomiting, abdominal pain, diarrhea, anorexia,
• Neutropenia
• Elevated AST/SGOT
• Thyroid dysfunction
• Musculoskeletal pain
• Asthenia, dizziness, fatigue, paresthesias
• Headache
• Depression, anxiety
• Cough dyspnea
• Edema
• Fever, influenza-like illness

Pharmacology

• Half-life: 2 to 160h
• Metabolism: Hepatic, renal (IFN-α₂A)
• Excretion: Renal

Mechanism of Action

• Interferons induce various cell activities, such as antiviral activity, suppression of cell proliferation, augmentation of macrophage activity and other immunomodulating effects.

See Also

• Antiviral
• Hepatitis B, Hepatitis C