Last reviewed 2026-04-22 · How we verify

Pegyinterferon-alfa-2a

Pegyinterferon-alfa-2a is a pegylated form of interferon-alfa that activates innate immune responses to suppress viral replication and inhibit cell proliferation.

Pegyinterferon-alfa-2a is a pegylated form of interferon-alfa that activates innate immune responses to suppress viral replication and inhibit cell proliferation. Used for Chronic hepatitis C, Chronic hepatitis B, Certain hematologic malignancies.

At a glance

Mechanism of action

The drug consists of interferon-alfa-2a conjugated to polyethylene glycol (PEG), which extends its half-life and reduces immunogenicity. It binds to interferon-alfa receptors on cell surfaces, triggering JAK-STAT signaling pathways that induce antiviral and antiproliferative gene expression. This mechanism makes it effective against chronic viral infections and certain malignancies.

Approved indications

• Chronic hepatitis C
• Chronic hepatitis B
• Certain hematologic malignancies

Common side effects

• Flu-like symptoms (fever, fatigue, myalgia)
• Headache
• Neutropenia
• Thrombocytopenia
• Depression/mood changes
• Injection site reactions
• Anemia

Key clinical trials

• An Open-label Trial of 48-week Peginterferon Alfa-2a (PEGASYS) to Assess the Sustained Response of Chronic Hepatitis B Patients With HBeAg Seroconversion on Nucleot(s)Ide Analogue Therapy (PHASE4)

Primary sources

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Competitive intelligence

For the full competitive landscape — auto-detected comparators, recent regulatory actions across the set, upcoming PDUFA, patent timeline, sponsor landscape:

• Pegyinterferon-alfa-2a CI brief — competitive landscape report
• Pegyinterferon-alfa-2a updates RSS · CI watch RSS
• Chinese University of Hong Kong portfolio CI