The US Food and Drug Administration (FDA) has expanded the indication for baloxavir marboxil tablets (Xofluza, Genentech) to include people at high risk of developing influenza-related complications.
The new indication regards patients with conditions such as asthma, chronic lung disease, diabetes, heart disease, or morbid obesity and for adults aged 65 years or older.
The FDA first approved baloxavir marboxil 1 year ago for the treatment of acute uncomplicated influenza in people aged 12 years or older who have been symptomatic for no more than 48 hours, as reported by Medscape Medical News.
The antiviral is given as a single oral dose.
"With the flu season rapidly approaching, we can now offer Xofluza as the first and only FDA-approved treatment option indicated specifically for those at high risk of flu complications," Levi Garraway, MD, PhD, Genentech chief medical officer and head of global product development, said in a company statement.
"People with chronic conditions such as asthma, heart disease and diabetes are at higher risk of developing serious complications from the flu, so it is critical that these patients speak with their healthcare providers about possible treatment at the first signs and symptoms of the disease," said Garraway.
Unlike neuraminidase inhibitors, such as oseltamivir (Tamiflu, Genentech), which inhibit the action of neuraminidase (an enzyme that frees viruses from the infected cells' surface), baloxavir marboxil prevents replication by inhibiting cap-dependent endonuclease activity of the viral polymerase.
The expanded indication for baloxavir marboxil was granted on the basis of results from the phase 3 CAPSTONE-2 study, which included people aged 12 years or older who met Centers for Disease Control and Prevention criteria for being at high risk for flu complications.
The study evaluated baloxavir marboxil 40 mg or 80 mg, given as a single dose, in comparison with oseltamivir 75 mg given twice daily for 5 days or placebo.
Baloxavir marboxil significantly reduced the time to improvement of flu symptoms compared to placebo (median time: 73 hours vs 102 hours; P < .001). Efficacy with respect to duration of symptoms was similar between baloxavir marboxil and oseltamivir (median time 73 hours vs 81 hours).
In people infected with influenza type B virus, the median time to improvement of flu symptoms was shorter with baloxavir marboxil compared to placebo (75 hours vs 101 hours).
Adverse events that were reported in at least 1% of adult and adolescent patients treated with baloxavir marboxil included diarrhea (3%), bronchitis (3%), nausea (2%), sinusitis (2%), and headache (1%).
Baloxavir marboxil is currently being studied in children younger than 1 year and in people hospitalized with severe flu, the company said. The potential of the antiviral to reduce transmission of the flu from an infected person to healthy people is under investigation.
Full prescribing information is available online.
Cite this: FDA Expands Xofluza Indication to People at High-Risk for Flu Complications - Medscape - Oct 17, 2019.