The US Food and Drug Administration (FDA) has granted approval of Xofluza (baloxavir marboxil) to Japanese pharmaceutical company Shionogi for the treatment of acute uncomplicated influenza (flu).
Said to be the first new antiviral influenza treatment in nearly 20 years, Xofluza is indicated for patients aged 12 years and above who have had symptoms for under 48 hours.
Xofluza is a first-in-class, oral, single-dose drug designed to inhibit the polymerase acidic endonuclease enzyme that is required for viral replication.
Discovered by Shionogi, the medicine is being developed in alliance with Roche Group, including Genentech in the US.
Roche chief medical officer and global product development head Sandra Horning said: “Xofluza is the first new flu medicine with a novel proposed mechanism of action approved in nearly 20 years, and we’re excited to offer a convenient treatment option that reduces flu symptoms by more than a day with a single oral dose.
“If patients see their doctors within 48 hours of symptom onset, one dose of Xofluza can significantly reduce the duration of flu symptoms.”
FDA approval is based on results from the multi-centre, randomised, double-blind, placebo-controlled Phase III CAPSTONE-1 clinical trial and a placebo-controlled Phase II study.
During the CAPSTONE-1 trial, a single Xofluza dose was compared to twice daily placebo or 75mg oseltamivir over five days in 1,436 otherwise healthy people with the flu in the US and Japan.
Findings showed that the drug significantly decreased the duration of flu symptoms compared to placebo, while its efficacy was similar to that of oseltamivir.
The most common adverse events in participants treated with Xofluza were diarrhoea, bronchitis, nausea, and sinusitis.
Xofluza will be available across the US over the coming weeks. Roche has the worldwide rights to the drug, excluding Japan and Taiwan, where Shionogi will be responsible.