Positive phase III results show Xofluza (baloxavir marboxil) significantly reduces the transmission of influenza viruses – Genentech/Roche

Genentech, a member of the Roche Group , announced t positive topline results of the Phase III CENTERSTONE study of Xofluza (baloxavir marboxil), an antiviral, showing a reduction in the transmission of influenza viruses. The study met its primary endpoint, demonstrating that a single, oral dose of Xofluza taken by people infected with influenza significantly reduced the likelihood of others in their household contracting the virus. Xofluza was well tolerated with no new safety signals identified.

CENTERSTONE is the first global Phase III study to show a transmission reduction benefit with an antiviral used in the treatment of a respiratory viral illness. This new data may add to the benefits of Xofluza which is currently approved for treating symptoms and preventing infection following virus exposure. The topline results will be presented at the 2024 OPTIONS XII for the Control of Influenza Congress (September 29 – October 2, Brisbane, Australia).

“Building on Xofluza’s established efficacy in treating and preventing influenza after exposure, this new evidence of transmission reduction represents an important advance that could help improve health outcomes at an individual and community level,” said Levi Garraway, M.D., Ph.D., chief medical officer and head of Global Product Development. “We look forward to discussing these data with regulatory authorities and public health organizations for influenza pandemic preparedness to bring these benefits to patients.”

Influenza is one of the most common yet serious infectious diseases representing a significant burden to public health. In the U.S., since 2010, seasonal influenza has infected up to 41 million people and has caused thousands of hospitalizations and 51,000 deaths annually. With the co-circulation and burden of multiple respiratory viruses (including COVID-19) infecting individuals within and outside of the winter season, it is more important than ever that influenza is not underestimated. For effective control of both seasonal and pandemic influenza, early diagnosis and treatment is critical.

The CENTERSTONE study has been partially supported with federal funds from the U.S. Department of Health and Human Services; Administration for Strategic Preparedness and Response; Biomedical Advanced Research and Development Authority, under Other Transaction Agreement number: HHSO100201800036C.

About CENTERSTONE

The CENTERSTONE study [NCT03969212] was a global Phase III trial investigating the efficacy of single-dose Xofluza, taken within 48 hours of symptoms onset, to reduce the onward transmission of influenza within households. The study ran across 272 sites across the globe, with over 4,000 participants, and involved otherwise healthy patients from five to 64 years who had been diagnosed with influenza via a Polymerase Chain Reaction (PCR) or rapid influenza diagnostic test, known as index patients (IPs) and those within their household (known as household contacts, HHCs). The primary endpoint was the proportion of HHCs who tested positive for influenza within five days after the IP had been treated with either Xofluza or placebo. The secondary endpoint looked at the proportion of HHCs who tested positive for influenza by Day five and developed influenza symptoms. The design of this randomized, placebo-controlled trial was developed with inputs from the U.S. Food and Drug Administration and leading experts in influenza.

Xofluza was discovered by Shionogi & Co., Ltd. and is being further developed and commercialized globally in collaboration with the Roche Group (which includes Genentech in the U.S.) and Shionogi & Co., Ltd. Under the terms of this agreement, Roche holds worldwide rights to Xofluza excluding Japan and Taiwan, which will be retained exclusively by Shionogi & Co., Ltd.