What is the dose of Baloxavir (Xofluza)?

From the Guidelines

Baloxavir should be dosed as a single oral dose, with the dose depending on the patient's weight: 2 mg/kg for individuals less than 20 kg, 40 mg for those weighing 20-80 kg, and 80 mg for those weighing more than 80 kg, as recommended in the 2024 study published in Pediatrics 1. The dosing of baloxavir is based on the patient's weight, and it is essential to follow the recommended dosing guidelines to ensure maximum effectiveness.

• For individuals less than 20 kg, the dose is 2 mg/kg as a single dose.
• For those weighing 20-80 kg, the dose is 40 mg as a single dose.
• For those weighing more than 80 kg, the dose is 80 mg as a single dose. It is crucial to note that baloxavir should be taken within 48 hours of symptom onset for maximum effectiveness, as it works by inhibiting the cap-dependent endonuclease enzyme needed for viral replication, as stated in the study 1. Some key points to consider when administering baloxavir include:
• The medication should be taken with or without food.
• It should not be taken with products containing calcium, iron, magnesium, selenium, or zinc, as these can reduce absorption, as mentioned in the study 1.
• Patients should be advised that even after taking baloxavir, they can still transmit influenza to others and should continue appropriate infection control measures. The study published in Pediatrics in 2024 provides the most recent and highest-quality evidence for the dosing of baloxavir, and it is essential to follow these guidelines to ensure the best possible outcomes for patients 1.

From the FDA Drug Label

2.2 Recommended Dosage Treatment of Acute Uncomplicated Influenza or Post-Exposure Prophylaxis in Adults, and Pediatric Patients (5 Years of Age and Older) XOFLUZA should be taken as a single dose as soon as possible and within 48 hours of influenza symptom onset for treatment of acute uncomplicated influenza or following contact with an individual who has influenza The recommended dosage of XOFLUZA in patients 5 years of age or older is a single weight-based dose displayed in Tables 1 and 2 Table 1 Recommended XOFLUZA Tablet Dosage in Adults and Pediatric Patients 5 Years of Age and Older Patient Body Weight (kg) | Recommended Single Oral Dose (Tablets) 20 kg to less than 80 kg | One 40 mg tablet At least 80 kg | One 80 mg tablet Table 2 Recommended XOFLUZA for Oral Suspension Dosage in Adults and Pediatric Patients 5 Years of Age and Older Patient Body Weight (kg) | Recommended Single Oral Dose*, † (For Oral Suspension) Less than 20 kg | 2 mg/kg taken as a single dose 20 kg to less than 80 kg | 40 mg (20 mL) taken as a single dose At least 80 kg | 80 mg (40 mL‡) taken as a single dose

The recommended dosage of Baloxavir is a single weight-based dose. For patients weighing 20 kg to less than 80 kg, the recommended dose is one 40 mg tablet or 40 mg (20 mL) of oral suspension. For patients weighing at least 80 kg, the recommended dose is one 80 mg tablet or 80 mg (40 mL) of oral suspension. For patients weighing less than 20 kg, the recommended dose is 2 mg/kg of oral suspension 2.

From the Research

Baloxavir Dose Information

• The dose of baloxavir marboxil (BXM) is administered orally as a single-dose of 40 mg or 80 mg, depending on body weight 3.
• No dosage adjustment is needed in patients with mild-to-moderate hepatic or renal impairment 3.
• In clinical trials, single-dose baloxavir was given as 40 mg or 80 mg, depending on the patient's weight, and was found to be effective in alleviating influenza symptoms 4.
• The efficacy and safety of baloxavir have been compared to other antivirals, such as neuraminidase inhibitors, in network meta-analyses, which suggest that baloxavir has a comparable safety profile and may have better efficacy results in some cases 5, 6.

Administration and Efficacy

• Baloxavir is approved by the Food and Drug Administration for the treatment of acute uncomplicated influenza in adults and adolescents 12 years of age and older who weigh at least 40 kg 3.
• Clinical trials have demonstrated that baloxavir is associated with a significantly shorter time to alleviation of influenza symptoms compared with placebo when taken within 48 hours of symptom onset 3, 4.
• The time to alleviation of symptoms was similar with baloxavir and oseltamivir in some studies 3, 4.
• Baloxavir has been shown to be effective in reducing viral load and alleviating influenza symptoms in patients with uncomplicated influenza 4, 6.

Special Considerations

• In immunocompromised patients, such as those who have undergone hematopoietic stem cell transplant, combination therapy with zanamivir and baloxavir may be effective in controlling persistent influenza and coronavirus infections 7.
• The use of baloxavir in combination with other antivirals may be a potential strategy for achieving influenza eradication in immunocompromised patients 7.