Please view the main text area of the page by skipping the main menu.

New one-time tablet popular this flu season, but experts urge caution

TOKYO -- Japan is about to hit peak flu season, and according to the Ministry of Health, Labor and Welfare, there were an estimated 313,000 patients nationwide over the week ending Dec. 23.

With the end of the New Year holidays and the reopening of companies and schools, there is a possibility that this number with grow even further. That is why this season, the new, highly convenient medicine "Xofluza" has come onto the scene, and is becoming the top choice to treat the flu.

There are four main types of medications on the market to treat influenza. However, after beginning sales this March, Xofluza is the first available in tablet form, and only needs to be taken once. According to Osaka-based pharmaceutical company Shionogi & Co., which developed the medicine, Xofluza accounted for 65 percent of its sales of anti-flu medicine from April to September this year.

Conventional flu treatments prevent the spread of the virus outside the cells in the body. However, Xofluza specifically targets the multiplication of the virus itself inside of the cells. Because of this, there is also a possibility that taking the medicine reduces transmittance of the virus to other people.

"The use of Xofluza is going to increase further," said Katsura Sugihara, a pediatrician and the head of Your Clinic Ochanomizu in Tokyo's Chiyoda Ward. The demand for only one pill to treat the virus from working people has been tremendous, he said. Before, there was an inhaler-type fine powder, but "Xofluza is a pill, so it is easy to swallow, and the reliability of its absorption rate inside the body is also very high," said Sugihara. However, the use is slated for those over 10 kilograms in weight, and children who cannot swallow tablets cannot be prescribed the drug.

Xofluza has been shown to be as effective in treating the flu as Tamiflu through international joint trials on adults, but since not much time has passed since the sales of the medicine began, there is still not enough data for conclusive results. Thus, the Japan Pediatric Society is not recommending the medication as a method to treat the flu in children this season.

On the other hand, some experts worry about the development of super viruses resistant to medications. In the joint international testing of Xofluza, resistant viruses were detected in 9.7 percent of adults and 23.3 percent of the children to which the drug was given. Both of these figures are higher than when patients are given Tamiflu. In the cases where the drug resistant strains developed, it took a longer period of time for symptoms such as fever to disappear.

"I am worried about the effects of the medication on patients with serious symptoms or bad conditions," said Norio Sugaya, head of the contagious disease control center at Keiyu Hospital in Yokohama.

A representative from Shionogi, on the other hand, said the company would "like to promote the proper use (of Xofluza) through the accumulation of effectiveness and safety data."

(Japanese original by Kaori Gomi and Satoshi Takano, Medical Welfare News Department)

Also in The Mainichi

The Mainichi on social media