Experts from the CDC have raised concerns about the emergence of resistance to baloxavir, emphasizing the need for ongoing global surveillance of resistant strains.

The CENTERSTONE trial involved 1,457 influenza-positive index patients and 2,681 household contacts across 15 countries from 2019 to 2024.

Participants were randomly assigned to receive either baloxavir or a placebo within 48 hours of symptom onset, with the primary goal of assessing transmission by day five.

Data from the trial indicated that patients treated with baloxavir experienced a marked decrease in viral shedding, a key factor in the spread of influenza.

Given that approximately one-third of influenza virus transmission occurs within households, these findings are particularly relevant for public health.

Influenza poses a significant health burden, infecting about one billion people globally each year and leading to millions of hospitalizations and up to 650,000 deaths.

Seasonal influenza causes approximately two days of absenteeism for 75% of working adults, impacting productivity even when symptoms are present.

While vaccines are the primary method for controlling influenza, antiviral drugs like baloxavir are important, especially in pandemic scenarios and among unvaccinated individuals.

Positive results from the Phase III CENTERSTONE trial of Xofluza (baloxavir marboxil) were recently published in the New England Journal of Medicine.

The trial achieved its primary endpoint, demonstrating a 32% reduction in influenza transmission among untreated household members compared to the placebo group.

The trial indicated that Xofluza was well tolerated, with no new safety issues reported, as adverse events occurred in 4.6% of baloxavir patients versus 7.0% in the placebo group.

During the study, 7.2% of patients in the baloxavir group developed drug-resistant viruses, but none were found in their household contacts, indicating limited spread of resistance.