What are the new influenza medications?

From the Guidelines

Baloxavir marboxil (Xofluza) is the newest FDA-approved influenza medication, offering a single-dose treatment option for uncomplicated influenza in patients 12 years and older who have been symptomatic for less than 48 hours. The standard adult dose is a one-time 40 mg oral dose for patients weighing 40-80 kg, or 80 mg for those weighing more than 80 kg. Unlike older antivirals like oseltamivir (Tamiflu) that require a 5-day course, baloxavir works through a different mechanism, inhibiting the cap-dependent endonuclease enzyme needed for viral replication. Clinical trials show it reduces symptom duration by about 24 hours and decreases viral shedding more rapidly than oseltamivir 1. Common side effects include diarrhea and bronchitis. For maximum effectiveness, treatment should be initiated within 48 hours of symptom onset. Patients should avoid taking products containing calcium, aluminum, iron, or zinc within 4 hours of baloxavir, as these can reduce absorption. While baloxavir offers convenience with its single-dose regimen, resistance can develop during treatment, so appropriate use and completing the full prescribed dose remains important.

Some key points to consider when prescribing baloxavir marboxil include:

• It is approved for use in patients 12 years and older
• The medication should be taken within 48 hours of symptom onset for maximum effectiveness
• Patients should be advised to avoid taking products containing calcium, aluminum, iron, or zinc within 4 hours of baloxavir
• Resistance can develop during treatment, so appropriate use and completing the full prescribed dose is crucial

It's also important to note that other antiviral medications, such as oseltamivir and zanamivir, are still effective and can be used to treat influenza, especially in patients who are not candidates for baloxavir marboxil 1. However, baloxavir marboxil is the newest and most convenient option, offering a single-dose treatment regimen. As with any medication, it's essential to monitor patients for potential side effects and adjust treatment as needed. By considering the latest evidence and guidelines, healthcare providers can make informed decisions about the best treatment options for their patients with influenza.

From the FDA Drug Label

RECENT MAJOR CHANGES Indications and UsageTreatment of Influenza (1.1)03/2024 The new influenza medication is baloxavir (PO), as indicated by the recent major change in its drug label for the treatment of influenza 2.

• Key points:
  • Drug Name: baloxavir (PO)
  • Indication: Treatment of Influenza
  • Date of change: 03/2024

From the Research

New Influenza Medications

• Oseltamivir is an oral neuraminidase inhibitor that has proven efficacy in reducing the duration and severity of acute influenza 3, 4, 5.
• It is effective in treating influenza in adults and children, and can also be used for prophylaxis in people who have had close contact with someone with influenza 3, 4, 5.
• Peramivir is an intravenously administered neuramidase inhibitor that has been compared to oseltamivir in terms of efficacy, with some studies suggesting that peramivir may reduce the time to alleviation of fever in patients with influenza 6.
• Oseltamivir has been shown to be effective in reducing the frequency of secondary illnesses and exacerbation of underlying conditions, and improving survival in seriously ill patients hospitalized with severe influenza 7.

Mechanism of Action

• Oseltamivir works by blocking the neuraminidase enzyme, which is crucial for influenza virion liberation from the host cell 3, 4, 5.
• Peramivir also works by inhibiting the neuraminidase enzyme, but is administered intravenously rather than orally 6.

Safety and Tolerability

• Oseltamivir is generally well tolerated, with a similar adverse event profile to placebo 3, 4, 5, 7.
• Peramivir has been shown to have a similar safety profile to oseltamivir, with no significant differences in adverse events between the two groups 6.
• Resistance to oseltamivir has been reported, but is relatively rare and has limited clinical impact 3, 7.