What is the efficacy comparison between Xofluza (Baloxavir) and Tamiflu (Oseltamivir)?

From the Guidelines

Xofluza (baloxavir marboxil) and Tamiflu (oseltamivir) have similar efficacy in reducing the duration of flu symptoms, but Xofluza has a faster reduction in viral load and may be more beneficial for high-risk patients or those who cannot adhere to a multi-day regimen, as shown in recent studies 1.

Key Differences Between Xofluza and Tamiflu

• Xofluza is a single-dose medication, while Tamiflu requires twice-daily dosing for 5 days
• Xofluza works by inhibiting the cap-dependent endonuclease enzyme, while Tamiflu blocks the neuraminidase enzyme
• Xofluza has a faster reduction in viral load, typically within 24 hours, compared to 72 hours with Tamiflu ### Efficacy and Safety
• Both medications are most effective when started within 48 hours of symptom onset
• Side effect profiles differ slightly, with Tamiflu more commonly causing nausea and vomiting, while Xofluza has fewer gastrointestinal side effects
• Resistance patterns also differ between the two medications, with some influenza strains showing resistance to one but not the other ### Recommendations
• Xofluza may be particularly beneficial for high-risk patients, such as those with underlying medical conditions or who are severely immunocompromised
• Tamiflu may be more suitable for patients who can adhere to a multi-day regimen and have no underlying medical conditions that may interact with the medication
• Clinical judgment and consideration of individual patient factors, such as disease severity and local influenza activity, are important in making treatment decisions 1, 2

From the FDA Drug Label

The primary endpoint of both trials, time to alleviation of symptoms, was defined as the time when all seven symptoms (cough, sore throat, nasal congestion, headache, feverishness, myalgia, and fatigue) had been assessed by the subject as none or mild for a duration of at least 21. 5 hours. In Trial T0831, there was no difference in the time to alleviation of symptoms between subjects (age ≥ 20 years) who received XOFLUZA (54 hours) and those who received oseltamivir (54 hours) In Trial T0832, ... There was no statistically significant difference in the median time to improvement of influenza symptoms in the subjects who received XOFLUZA (73 hours) and those who received oseltamivir (81 hours)

The efficacy comparison between Xofluza (Baloxavir) and Tamiflu (Oseltamivir) shows no statistically significant difference in the time to alleviation or improvement of influenza symptoms in two trials, Trial T0831 and Trial T0832, with median times to alleviation or improvement of symptoms being similar between the two treatments 3.

• Key findings: + No difference in time to alleviation of symptoms between Xofluza and oseltamivir in Trial T0831 + No statistically significant difference in median time to improvement of influenza symptoms between Xofluza and oseltamivir in Trial T0832
• Main conclusion: Xofluza and oseltamivir have similar efficacy in the treatment of acute uncomplicated influenza 3.

From the Research

Efficacy Comparison

• The efficacy of Xofluza (Baloxavir) and Tamiflu (Oseltamivir) has been compared in several studies 4, 5, 6, 7, 8.
• Baloxavir has been shown to be as effective as oseltamivir in improving influenza symptoms in otherwise healthy adolescents and adults, as well as in those at high risk of influenza complications 4, 7.
• Baloxavir has also been found to reduce influenza viral load more rapidly than oseltamivir 4, 5, 7.
• A study published in 2020 found that single-dose baloxavir had superior efficacy to placebo and similar efficacy to oseltamivir for ameliorating influenza symptoms in high-risk outpatients 6.
• A real-world study published in 2024 found that baloxavir marboxil was superior to oseltamivir in alleviating influenza symptoms in outpatients with uncomplicated influenza, particularly when given within 12-48 hours after symptom onset 8.

Time to Alleviation of Symptoms

• The median time to alleviation of influenza symptoms was shorter in the baloxavir group compared to the oseltamivir group in several studies 6, 7, 8.
• A study published in 2020 found that the median time to alleviation of symptoms was 73.2 hours with baloxavir, compared to 81.0 hours with oseltamivir 6.
• A real-world study published in 2024 found that the median time to alleviation of all influenza symptoms was 28.0 hours with baloxavir marboxil, compared to 48.0 hours with oseltamivir 8.

Safety

• Baloxavir has been found to be well tolerated, with similar adverse event rates compared to oseltamivir 4, 5, 6, 7, 8.
• A study published in 2020 found that adverse events were reported in 25% of baloxavir recipients, compared to 30% of placebo recipients and 28% of oseltamivir recipients 6.
• A real-world study published in 2024 found that there was no significant difference in the rate of adverse events between the baloxavir marboxil and oseltamivir groups 8.