Interferon alfa-1b

Summary

Interferon alfa-1b is a recombinant type I interferon with antiviral, antiproliferative, and immunomodulatory properties. It is approved primarily in certain Asian markets (notably Japan and China) for indications including chronic hepatitis B, chronic hepatitis C, and certain malignancies. It is structurally related to other interferon alfa subtypes but is a distinct molecular species.

Mechanism of Action

Binds to the type I interferon receptor (IFNAR1/IFNAR2) on cell surfaces, activating the JAK-STAT signaling pathway (JAK1/TYK2), leading to transcription of interferon-stimulated genes (ISGs) that mediate antiviral, antiproliferative, and immunomodulatory effects.

Routes of Administration

Goals & Uses

• Chronic Hepatitis C treatmentAntiviralHigh
• Chronic Hepatitis B treatmentAntiviralHigh
• Condylomata acuminataAntiviral / DermatologyModerate
• Hairy cell leukemiaOncologyModerate
• Chronic myelogenous leukemia (CML)OncologyModerate

Contraindications

• Severe psychiatric disorders (e.g., severe depression, psychosis)PsychiatricHigh
• PregnancyPopulationHighPotential fetal risk or insufficient safety data
• Severe renal or cardiac insufficiencyOrgan ImpairmentModerate
• Autoimmune hepatitisHepatic / AutoimmuneHigh
• Decompensated liver diseaseHepatic ImpairmentHigh
• Hypersensitivity to interferon alfa or any componentImmunologicHigh

Adverse Effects

• Flu-like syndrome (fever, chills, myalgia, headache)SystemicCommon
• Neuropsychiatric effects (depression, irritability, suicidal ideation)PsychiatricCommon
• Injection site reactionsLocalCommon
• Elevated liver enzymes / hepatotoxicityHepaticUncommon
• Myelosuppression (neutropenia, thrombocytopenia, anemia)HematologicCommon
• Thyroid dysfunction (hypo- or hyperthyroidism)EndocrineUncommon

Drug Interactions

• Immunosuppressants (e.g., corticosteroids)Moderate
• Zidovudine (AZT)Moderate
• Theophylline / AminophyllineModerate
• RibavirinLow
• ClozapineHigh

Population Constraints

• Renal impairmentOrgan ImpairmentRelative
• Pediatric patientsAgeRelative
• Patients with pre-existing psychiatric illnessPsychiatricRelative
• Patients with autoimmune diseaseAutoimmuneRelative
• Elderly patients (≥65 years)Age RelatedRelative

Regulatory Status

• European UnionUnapprovedNot independently approved by the EMA as a distinct product.
• United StatesUnapprovedInterferon alfa-1b is not independently approved by the FDA; alfa-2a and alfa-2b are approved in the US.
• United KingdomUnknownNo independent MHRA approval identified for interferon alfa-1b specifically.

Approved in Japan (as Sumiferon) and China for chronic viral hepatitis and some oncologic indications. Not independently approved by the US FDA or EMA as a distinct product; other interferon alfa products (alfa-2a, alfa-2b) are approved in Western markets.

Evidence & Sources

No sources recorded yet.