FDA Approves Baloxavir Marboxil to Treat Influenza in Children Aged 5 to 11

The FDA approved a supplemental New Drug Application (sNDA) for baloxavir marboxil (Xofluza; Genentech), which is an acute and uncomplicated influenza (flu) treatment. Baloxavir marboxil is a single-dose oral flu medicine that is the first and only drug of its kind that has been approved for this age group.

The FDA approved baloxavir marboxil to treat healthy children aged 5 to 11 years who are symptomatic for less than 2 days with the flu. It is also approved to prevent the flu in children aged 5 to 11 years who have encountered someone with the flu. The FDA approved baloxavir marboxil following the miniSTONE-2 and BLOCKSTONE phase 3 studies.

“Today’s FDA approval provides children with a single-dose antiviral option, Xofluza, to treat influenza," said miniSTONE-2 study investigator Pedro Piedra, MD, professor of molecular virology and microbiology, pediatrics at Baylor College of Medicine, in a statement.

From 2018 to 2019, more than 6 million children contracted a strain of the flu. Further, the severity of the flu can vary from mild to deadly. From 2018-2019, the flu killed more than 100 children aged 5 to 17 years. In the press release, the CDC added that recent social distancing and mask wearing during the COVID-19 pandemic significantly reduced flu cases in children.

“Despite the ongoing COVID-19 pandemic, influenza continues to be a threat to public health, and effective influenza antivirals remain critical to alleviating the burden on healthcare systems,” Levi Garraway, MD, PhD, chief medical officer and head of Global Product Development, said in the press release. “Xofluza has proven to be an important tool in fighting and preventing influenza in adults as well as adolescents, and we are pleased to now offer households and younger children our single-dose oral treatment.”

In the miniSTONE-2 phase 3 trial, researchers compared baloxavir marboxil with oseltamivir, evaluating healthy children aged 5 to 11 years with less than 48 hours of symptoms. During the BLOCKSTONE phase 3 trial, researchers evaluated baloxavir marboxil as a preventative treatment for household members living with someone diagnosed with the flu.

As one of the largest transmitters of the flu virus, children can also play a significant role in transmission of the virus within the home, as well as beyond it.

“Historically, school-aged children have played a significant role in the community transmission of influenza. The annual influenza vaccine continues to be the most important first step to prevent illness in children, though there can still be breakthrough cases where antiviral treatment is needed,” Piedra said in the statement.

Baloxavir marboxil was shown in non-clinical studies to be effective against multiple flu strains. The FDA approved baloxavir marboxil back in 2018 to treat acute, uncomplicated flu in healthy individuals aged 12 years with less than 48 hours of symptoms. When approved in 2018, it marked the first new flu antiviral in 20 years. That same year, it was also approved as a one-dose, single tablet for individuals aged 12 years and older exposed to the flu.

Among pediatric patients, 5% reported adverse effects—of this percentage, 5% reported vomiting and 5% reported diarrhea. Researchers are now studying baloxavir marboxil in children who are aged younger than 1 year in a phase 3 development program (NCT03653364).

Reference

Genentech Announces FDA Approval of Xofluza to Treat Influenza in Children Aged Five and Older. San Francisco, CA: Genentech; Aug 11, 2022. Accessed on Aug 12, 2022. https://www.businesswire.com/news/home/20220815005009/en