Last reviewed 2026-04-22 · How we verify

CS-8958

CS-8958 is a neuraminidase inhibitor that prevents influenza virus release from infected cells by blocking sialic acid cleavage.

CS-8958 is a neuraminidase inhibitor that prevents influenza virus release from infected cells by blocking sialic acid cleavage. Used for Acute uncomplicated influenza A and B infection in adults and children.

At a glance

Mechanism of action

CS-8958 (peramivir) inhibits viral neuraminidase, an enzyme required for the release of newly formed influenza virus particles from host cells. By blocking this enzyme, the drug prevents viral spread and reduces the duration and severity of influenza infection. It is active against both influenza A and B viruses.

Approved indications

• Acute uncomplicated influenza A and B infection in adults and children

Common side effects

• Diarrhea
• Nausea
• Vomiting
• Headache

Key clinical trials

• Safety & Pharmacokinetics Study of Inhaled Laninamivir Octanoate TwinCaps® Dry Powder Inhaler in Children With Influenza (PHASE1, PHASE2)
• A Multinational Phase III Study of CS-8958 (MARVEL) (PHASE3)
• CS-8958 Single Inhaled Dose in Elderly (PHASE1)
• Efficacy and Safety Study of Laninamivir Octanoate TwinCaps® Dry Powder Inhaler in Adults With Influenza (PHASE2)
• Safety, Tolerability and Pharmacokinetic Study of Multiple Doses of CS-8958 (PHASE1)
• Safety, Tolerability and Pharmacokinetics of Inhaled Laninamivir Octanoate TwinCaps® DPI in Adults With Chronic Asthma (PHASE1)
• Safety, Tolerability and Pharmacokinetic Study of Biota-CS-8958 (PHASE1)

Primary sources

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