First New Antiviral for Influenza in 2 Decades Approved by FDA

Officials with the FDA have approved baloxavir marboxil (Xofluza, Shionogi) for the treatment of acute uncomplicated influenza in patients aged 12 years and older who have been symptomatic for no more than 48 hours.

The approval marks the first new antiviral flu treatment with a novel mechanism of action backed by the agency in nearly 20 years, according to FDA Commissioner Scott Gottlieb, MD.

“With thousands of people getting the flu every year, and many people becoming seriously ill, having safe and effective treatment alternatives is critical. This novel drug provides an important, additional treatment option,” said Gottlieb, in a prepared statement.

The safety and efficacy of baloxavir marboxil, an antiviral drug taken as a single oral dose, was demonstrated in 2 randomized controlled clinical trials of 1,832 patients where participants were assigned to receive either Xofluza, a placebo, or another antiviral flu treatment within 48 hours of experiencing flu symptoms. In both trials, patients treated with Xofluza had a shorter time to alleviation of symptoms compared with patients who took the placebo. In the second trial, there was no difference in the time to alleviation of symptoms between subjects who received Xofluza and those who received the other flu treatment.

The most common adverse reactions in patients taking baloxavir marboxil were diarrhea and bronchitis.

Flu is a contagious respiratory illness caused by influenza viruses. When patients with the flu are treated within 48 hours of becoming sick, antiviral drugs can reduce symptoms and duration of the illness, according to the FDA.

“When treatment is started within 48 hours of becoming sick with flu symptoms, antiviral drugs can lessen symptoms and shorten the time patients feel sick,” said Debra Birnkrant, MD, director of the Division of Antiviral Products in the FDA’s Center for Drug Evaluation and Research, in a prepared statement. “Having more treatment options that work in different ways to attack the virus is important because flu viruses can become resistant to antiviral drugs.”

Xofluza was granted FDA approval under a Priority Review designation.

Despite several FDA-approved antiviral drugs to treat flu, Gottlieb said, they are not a substitute for yearly vaccination. Flu season is already well underway, and the CDC recommends getting vaccinated by the end of October.

“Seasonal flu vaccine is one of the most effective and safest ways to protect yourself, your family and your community from the flu and serious flu-related complications, which can result in hospitalizations. Yearly vaccination is the primary means of preventing and controlling flu outbreaks,” said Gottlieb, in a prepared statement.

Reference

FDA approves new drug to treat influenza [news release]. Silver Spring, MD; October 24, 2018: FDA website. http://www.pharmacytimes.com/link/225. Accessed October 24, 2018.