Xofluza

Overview

What is Xofluza?

Xofluza, known generically as baloxavir marboxil, is an antiviral medication used for the treatment of influenza A and B. Unlike neuraminidase inhibitors such as Tamiflu, Xofluza works by inhibiting the cap-dependent endonuclease enzyme, which is essential for viral replication. This unique mechanism helps stop the flu virus from multiplying in the body. The active ingredient is baloxavir marboxil.

Global Name

• Generic name: Baloxavir marboxil
• Brand name: Xofluza

Usage

What is Xofluza used for?

Xofluza is used to:

• Treat acute uncomplicated influenza in patients 5 years of age and older who have had flu symptoms for no more than 48 hours, and who are otherwise healthy or at high risk of developing influenza-related complications.
• Reduce the risk of developing flu after exposure to someone who is infected (as post-exposure prophylaxis in patients aged 5 years or above).
  
  

How do you use Xofluza?

Formulation:

Available in both oral tablet and oral suspension formulations. However, only the tablet form is currently registered in Hong Kong.

Dosage information:
Tablet dosage based on body weight

• 40 mg for patients weighing 20 to <80 kg
• 80 mg for patients weighing ≥80 kg

Are the following suitable for getting the drug?

• Children: Suitable for children aged 5 years or older
• Adults: Suitable for adults.
• Elderlies: Suitable for elderly patients. No dose adjustment is required.

• Children: Not recommended for children under 5 years old.
• Adults: Those with severe renal or hepatic impairments.
• Elderlies: Those with severe renal or hepatic impairments.
• Pregnancy: No adequate data to inform a drug-associated risk of adverse developmental outcomes. Consult a doctor before use.
• Lactation: No data on the presence of Xofluza in human milk, the effects on the breastfed infant, or the effects on milk production. Consult a doctor before use.
• Allergies: Avoid if allergic to baloxavir marboxil or any of its components of the drug.

Warnings and Precautions:

• Hypersensitivity: Initiate appropriate treatment if anaphylaxis, angioedema, urticaria and erythema multiforme occurs or is suspected.
• Increased incidence of treatment-emergent resistance in patients less than 5 years of age. It is not known if XOFLUZA is safe and effective for the treatment and prevention of the flu in children less than 5 years of age.
• Risk of bacterial infection: XOFLUZA does not prevent bacterial infections that may happen with the flu.

Interactions and Contraindications of Xofluza: 

• Interactions: Avoid coadministration with dairy products, calcium-fortified beverages, or supplements containing polyvalent cations-containing laxatives, antacids or oral supplements (e.g., calcium, magnesium, iron, zinc, selenium).
• Conditions: Concurrent administration of antiviral drugs may inhibit viral replication of live attenuated influenza vaccine (LAIV) and thereby decrease the effectiveness of LAIV vaccination.
• Contraindications: Avoid Xofluza in patients with a history of hypersensitivity to baloxavir marboxil or any of its ingredients. 

Side Effects

Common side effects in adults and adolescents may include:

• Diarrhea (3%)
• Bronchitis (3%)
• Nausea (2%)
• Sinusitis (2%)
• Headache (1%)

• Vomiting (5%)
• Diarrhea (5%)

Serious side effects may include:

• Allergic reactions such as trouble breathing, skin rash, hives or blisters, swelling of face, throat or mouth, dizziness or lightheadedness

Pharmacist Tips

• Storage information: Store the tablets in their blister package at room temperature.
• Administration: Take Xofluza with or without food.

Availability

Where is Xofluza available in Hong Kong?

Xofluza is a prescription medication available through healthcare providers upon doctor’s prescription.

FAQs

What is Xofluza?

Xofluza (generic name: baloxavir marboxil) is an antiviral medicine. It works by blocking an enzyme that the flu virus needs to replicate.  

Is Xofluza effective?

Yes. Xofluza is effective against both influenza A and B. Clinical studies show that it can shorten the course of illness, relieve symptoms, and reduce the risk of contracting the virus. Patients aged 12 years or older can feel better with Xofluza in just over 2 days.

How do you take Xofluza?

Xofluza is taken as a single oral dose, with the amount depending on body weight. It can be taken with or without food but should not be taken at the same time with dairy products or supplements containing calcium, iron, selenium, magnesium or zinc. 

How much does Xofluza cost?

Xofluza is a prescription-only medicine, and the price varies depending on the healthcare provider.