A large retrospective cohort analysis of real-world electronic health record data suggests that baloxavir (Xofluza) may reduce hospitalizations and emergency department (ED) visits more effectively than oseltamivir (Tamiflu) in patients treated for influenza.
The study, published in the International Journal of Infectious Diseases, compared outcomes among more than 75,000 US patients, offering new insights on the effectiveness of these two antiviral drugs.
Researchers gathered data from 69 healthcare organizations to identify influenza patients five years and older who received either oseltamivir (73,899) or baloxavir (1,592) from 2016 to 2023. After excluding patients who were treated in the ED or admitted to the hospital and controlling for baseline differences and possible confounders, the team compared outcomes for 1,592 patients in each group.
Baloxavir cut more hospitalizations in females, younger adults
Across one-, three-, and six-month follow-up periods, baloxavir was consistently associated with substantially fewer hospitalizations. At six months, 5.3% of oseltamivir users had been hospitalized, compared with just 0.8% of baloxavir users. Similar patterns emerged at one and three months.
ED visits were also more frequent among oseltamivir users, though the differences were smaller. At six months, 7.2% of oseltamivir recipients had visited the ED versus 5.0% of baloxavir recipients. Deaths were rare in both groups (0.6%).
A more granular analysis of the data showed that baloxavir significantly reduced ED visits and hospitalizations among females and patients younger than 50 years. Outcomes in adults 50 and older were more variable, though trends generally still favored baloxavir.
Real-world effectiveness aligns with earlier findings
The authors note that earlier trials have suggested that baloxavir may more rapidly reduce viral load and help resolve symptoms than oseltamivir, findings broadly consistent with previous real-world clinical trials. The new data suggest that baloxavir may meaningfully reduce health care use, an important consideration during high-severity flu seasons.
The study’s limitations include its retrospective design, smaller number of baloxavir users, limited racial diversity, and absence of patient-reported outcomes. The authors call for additional research across diverse populations and note the need to incorporate patient-reported outcomes and cost-effectiveness analyses.
