Last reviewed 2026-04-20 · How we verify

TECOVIRIMAT MONOHYDRATE

Tecovirimat is an antiviral drug that targets the variola (smallpox) virus.

Tecovirimat monohydrate is a marketed antiviral drug specifically designed to treat human smallpox disease, positioning it as a critical therapeutic in biodefense and public health preparedness. Its key strength lies in its targeted mechanism against the variola virus, providing a unique solution in the event of a smallpox outbreak or bioterrorism incident. The primary risk is the expiration of its key composition patent in 2028, which could lead to increased competition from generic versions.

At a glance

Mechanism of action

Tecovirimat works by specifically inhibiting the variola virus, which causes smallpox. This antiviral activity helps to prevent the virus from replicating and spreading within the body.

Approved indications

• Treatment of Human Smallpox Disease

Common side effects

• Headache
• Nausea
• Abdominal pain
• Vomiting
• Infusion Site Pain
• Infusion Site Swelling
• Infusion Site Erythema
• Infusion Site Extravasation
• Headache

Drug interactions

• Repaglinide
• Midazolam
• Calcium acetate
• Lanthanum carbonate
• Sevelamer carbonate
• Sucroferric oxyhydroxide

Key clinical trials

• Tecovirimat in Non-hospitalized Patients With Monkeypox (PHASE3)
• Assessment of the Efficacy and Safety of Tecovirimat in Patients With Monkeypox Virus Disease (PHASE3)
• Phase I Trial of an Investigational Small Pox Medication (PHASE1)

Primary sources

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