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Tecovirimat Monohydrate

Tecovirimat SIGA · ATC code J05AX24

Also known as: Tekovirimat

Key facts
Active substance
Tecovirimat Monohydrate
Drug class
Enisamium iodide
ATC code
J05AX24
Authorisation
centrally authorised across the EU (EMA)
Dosage forms
Tecovirimat SIGA 200 mg hard capsules
Marketing authorisation holder
SIGA Technologies Netherlands B.V.
Information as of
2026-10-29

Key facts

Tecovirimat (Tecovirimat SIGA, as monohydrate) is an oral antiviral against orthopoxviruses used for smallpox, cowpox and complications after smallpox vaccination.

What it is used for

  • Treatment of smallpox and cowpox in adults and children weighing at least 13 kg.
  • Treatment of complications due to vaccinia virus replication following smallpox vaccination in adults and children weighing at least 13 kg.
  • Use in accordance with official recommendations.

Dosing

  • Start as soon as possible after diagnosis; treatment lasts 14 days, taken within 30 minutes after a moderate- or high-fat meal.
  • 13 kg to less than 25 kg: 200 mg (one capsule) every 12 hours; 25 kg to less than 40 kg: 400 mg every 12 hours; 40 kg to less than 120 kg: 600 mg every 12 hours; 120 kg and above: 600 mg every 8 hours.
  • Vomiting within 30 minutes: repeat the dose immediately; later, no extra dose.
  • No dose adjustment in the elderly or in renal or hepatic impairment. Not for children under 13 kg.
  • Capsules may be opened and mixed with approximately 30 mL of liquid or soft food.

Contraindications

  • Hypersensitivity to the active substance or any excipient.

Important warnings

  • With repaglinide, mild to moderate hypoglycaemia may occur – monitor blood glucose.
  • May reduce the effectiveness of midazolam.
  • Caution in severe renal or hepatic impairment (limited data).
  • Not evaluated in immunocompromised individuals; efficacy may be reduced.
  • Contains lactose.

Side effects

  • Most frequent: headache (12.3%) and nausea (4.5%).
  • Also common: dizziness, upper abdominal pain, abdominal discomfort, diarrhoea, vomiting.
  • Uncommon include blood count changes, elevated liver tests, anxiety, depression, insomnia, palpitations.

Interactions

  • Phosphate binders may slightly increase tecovirimat exposure (calcium acetate: AUC up 16%) – monitor for adverse effects.
  • Monitor with repaglinide (hypoglycaemia) and midazolam (reduced effect).
  • In animal studies, co-administration with live smallpox vaccine may reduce the vaccine response.

Pregnancy and breastfeeding

  • Not recommended during pregnancy; breast-feeding should be discontinued during treatment.

Summary of the official product information, written with AI on 2026-10-29. Every number was checked automatically against the original text. Not reviewed by a physician – the full official text is authoritative.

Full official text →

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For patients

Package leaflet, verbatim

This product has no separate US patient information.

Authorisation and brand names by country

Medicines with exactly this active-substance composition, as listed in the national registers – alphabetical and without ranking. Whether a product is currently available is not shown here.

EU – centrally authorised (all member states)

Source: European Medicines Agency (EMA), product information

Medelix receives no money from pharmaceutical companies. Brand names are listed alphabetically and without ranking.

Other substances in the same group

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Sources

  1. European Medicines Agency. Tecovirimat SIGA – EPAR, Product Information. 2026-10-29. https://www.ema.europa.eu/en/documents/product-information/tecovirimat-siga-epar-product-information_en.pdf
  2. Wikidata (CC0): ATC J05AX.

Editorial: Medelix editorial team · last updated 2026-10-29 · How these pages are made · Report an error

Source: European Medicines Agency (EMA), product information. Not advertising, not a treatment recommendation. For questions about your own treatment, ask your doctor or pharmacist.