For the first time in almost two decades, the US Food and Drug Administration (FDA) approved a drug to combat the flu in people over 12 years old after symptoms have started.
The approval, announced on Wednesday (Oct. 24), comes just in time for the ramping up of flu season in the northern hemisphere. In late June, it was given priority review status by the FDA, meaning regulators had to come to a consensus within six months. There have already been a handful of deaths as a result of the flu so far in the US, and last year the flu killed 80,000 individuals.
The drug, known generically as baloxavir marboxil but sold under the brand name Xofluza, was invented and is manufactured by the Japanese company Shionogi & Co. It’s a novel antiviral drug administered with just one pill after the first two days a person has symptoms of the flu. In two clinical trials of over 1,800 patients, Xofluza shortened the time people were sick (paywall) with the flu by about a day, compared to a placebo—roughly the same effect as the other antiviral on the market, Tamiflu. In the US, Xofluza will be manufactured by Genentech, which is owned by Roche, which makes Tamiflu. (There was a third type of drug for the flu, but it was discontinued after 2016 as the influenza virus developed resistance against it.)
“This is the most potent single agent that I’ve seen to date in terms of its effect on replication in acute influenza,” Frederick Hayden, an infectious disease specialist at the University of Virginia, told STAT. Hayden worked on the drug for Shionogi, but his payment went to charity.
In many cases, one pill (or dose) will suffice, though two might be required depending on a patient’s weight and the pill’s strength. Either way, Xofluza is more convenient than Tamiflu, which is given in 10 pills over the course of five days. However, both treatments require that patients see their physicians within the first day or two that they start feeling the characteristic fever chills and sore throat—which may be difficult for patients.
In Japan, where the drug was approved in February, a single pill costs $43.50; Genentech has provided a coupon for it online for as little as $30 (pdf).
The easiest way to prevent the flu is to get a flu shot. Although these vaccines are not 100% effective, it’s worth getting a shot anyway; they can prevent the symptoms of the flu from being severe.
Clarification: This story has been updated to indicate that two Xofluza pills might be required in some cases.