Uses

Baloxavir marboxil is an influenza virus PA endonuclease inhibitor indicated for treatment of acute uncomplicated influenza in patients aged 5 years and older who have been symptomatic for no more than 48 hours, including those at high risk of complications. It is also indicated for post-exposure prophylaxis of influenza following contact with a confirmed influenza case.

Do not use if

Contraindicated in patients with a known history of hypersensitivity to baloxavir marboxil or any component of the formulation, including serious allergic reactions such as anaphylaxis, angioedema, urticaria, and erythema multiforme.

Side effects

In adults and adolescents, the most commonly reported adverse events include diarrhea, bronchitis, nausea, sinusitis, and headache. In children aged 5–12 years, vomiting and diarrhea are the most frequently reported events.

Warnings

Risk of hypersensitivity reactions including anaphylaxis; discontinue immediately if such reactions occur. Not recommended in children under 5 years due to increased treatment-emergent resistance. Dairy products and polyvalent cation-containing products (e.g., antacids, laxatives) may reduce efficacy and should be avoided close to dosing.

How it works

Baloxavir marboxil is a prodrug converted to baloxavir acid, which inhibits the cap-dependent endonuclease activity of the influenza virus PA protein, thereby blocking viral RNA transcription and replication. Its single-dose regimen reflects its unique mechanism distinct from neuraminidase inhibitors.

Storage

Store tablets in their blister packaging at 20°C to 25°C (68°F to 77°F); excursions permitted between 15°C and 30°C (59°F to 86°F).