Xofluza Baloxavir Marboxil Powder for Oral Suspension

1. Indications and Usage
XOFLUZA is indicated for the treatment of acute influenza in patients 12 weeks of age and older who have been symptomatic for no more than 48 hours.
2. Dosage and Administration
Route: Oral administration.
Recommended Dose: A single oral dose based on patient body weight.
< 20 kg: 2 mg/kg.
≥ 20 kg to < 80 kg: 40 mg.
≥ 80 kg: 80 mg.
Administration: The oral suspension should be prepared by adding 20 mL of water to the bottle and shaking gently to mix. The prepared suspension should be taken within 2 hours of preparation.
Administration with Food: Can be taken with or without food.
Concurrent Use with Metal Ions: Do not administer baloxavir marboxil concomitantly with乳制品, calcium-fortified drinks, laxatives, antacids, or oral supplements containing calcium, iron, magnesium, selenium, or zinc.
3. Mechanism of Action
Baloxavir marboxil is a prodrug of baloxavir acid, which is a selective inhibitor of the influenza virus RNA-dependent RNA polymerase subunit PA. By binding to the PA subunit of the viral polymerase complex, baloxavir acid inhibits viral transcription and replication, thereby preventing the spread of the virus.
4. Safety and Warnings
Hypersensitivity Reactions: Serious hypersensitivity reactions, including anaphylaxis, angioedema, and Stevens-Johnson syndrome, have been reported. Discontinue immediately if a serious allergic reaction occurs.
Neuropsychiatric Events: Rare cases of neuropsychiatric events have been reported in patients with influenza. Patients should be observed for abnormal behavior, and appropriate medical management should be sought if necessary.
Severe Skin and Mucous Membrane Reactions: Discontinue at the first appearance of a rash or any signs of severe skin reactions.
5. Adverse Reactions and Clinical Research
Adverse Reactions: The most common adverse reactions (incidence ≥1%) in adult and adolescent patients included diarrhea, bronchitis, nausea, sinusitis, and headache.
Clinical Research: Efficacy was established in three randomized, double-blind, placebo-controlled trials in patients with acute uncomplicated influenza. Baloxavir marboxil demonstrated a significant reduction in the time to symptom alleviation compared with placebo.
6. Drug Interactions
Metal Ions: Multivalent cations (e.g., calcium, iron, magnesium) can form chelates with baloxavir, significantly reducing its oral absorption.
Antacids and Laxatives: Products containing magnesium, aluminum, calcium, or iron may reduce the absorption of baloxavir marboxil.
CYP/UGT Enzymes: Baloxavir marboxil and baloxavir are not expected to inhibit or induce CYP or UGT family isoenzymes. No clinically significant pharmacokinetic interactions with small-molecule drugs mediated by these enzymes are expected.
7. Pharmaceutical Information
Active Ingredient: Baloxavir marboxil.
Description: The oral suspension is a white to off-white powder that, when reconstituted with water, forms a white to pale yellow suspension.
Strengths: The powder contains baloxavir marboxil equivalent to 20 mg/mL of baloxavir after reconstitution.
Storage: Store the unopened bottle at room temperature (20°C to 25°C or 68°F to 77°F).