FDA Expands Use of Oseltamivir to Infants

Mark Crane


December 21, 2012

The US Food and Drug Administration (FDA) today expanded the approved use of oseltamivir (Tamiflu, Genentech) to treat children as young as 2 weeks old who have shown symptoms of influenza for no longer than 2 days.

The drug is not approved to prevent flu infection in this population. In addition, the safety and efficacy of oseltamivir to treat flu infection have not been established in children younger than 2 weeks old.

Although there is a fixed-dosing regimen for patients aged 1 year and older according to weight categories, the dosing for children younger than 1 year must be calculated for each patient according to the child's exact weight, the FDA said in a press release. These children should receive 3 mg/kg twice daily for 5 days. These smaller doses will require a different dispenser than what is currently co-packaged with oseltamivir.

"Pharmacists must provide the proper dispenser when filling a prescription so parents can measure and administer the correct dose to their children," Edward Cox, MD, MPH, director of the Office of Antimicrobial Products in the FDA's Center for Drug Evaluation and Research, said in the press release. "Parents and pediatricians must make sure children receive only the amount of Tamiflu appropriate for their weight."

Oseltamivir was approved in 1999 to treat adults infected with influenza who have shown symptoms for no longer than 2 days. It is the only product approved to treat flu infection in children younger than 1 year. According to the Centers for Disease Control and Prevention (CDC), children younger than 2 years are at higher risk of developing complications from the flu, with the highest rates of hospitalization in those younger than 6 months.

Oseltamivir is not a substitute for early, annual influenza vaccination, as recommended by the CDC's Advisory Committee on Immunization Practices, the FDA said. The CDC recommends that all persons aged 6 months and older receive an annual flu vaccine.

The FDA expanded the approved use of oseltamivir in children younger than 1 year on the basis of extrapolation of data from previous study results in adults and older children, and additional supporting safety and pharmacokinetic studies sponsored by both the National Institutes of Health and Roche Group, oseltamivir's manufacturer.

The most common adverse effects reported with oseltamivir use in this age group include vomiting and diarrhea. Although not seen in the new studies, rare cases of severe rash, skin reactions, hallucinations, delirium, and abnormal behavior have been reported.

Last month, the British Medical Journal alleged that Roche is deliberately hiding clinical trial data about the efficacy of oseltamivir in patients with influenza and that it concealed neurologic and psychiatric adverse events associated with the drug.

In a media statement, Roche denied withholding clinical data and said it has made "full clinical study data available to health authorities around the world."

Tamiflu is distributed in the United States by South San Francisco–based Genentech, a member of the Roche Group.