Roche's Super Flu Drug Xofluza Demonstrates Significant Risk Reduction in Influenza Infection in Phase III Preventive Trial

June 07, 2019 /BioValleyBIOON/ -- Swiss pharmaceutical giant Roche recently announced that the Phase III clinical study BLOCKSTONE, evaluating the prophylactic treatment of influenza with the drug Xofluza (baloxavir marboxil), had met its primary endpoint. The results showed that, among healthy subjects with family members suffering from influenza, prophylactic treatment with Xofluza significantly reduced the risk of developing influenza compared to placebo.

BLOCKSTONE is a randomized, placebo-controlled, Phase III post-exposure prophylaxis study conducted by Shionogi during the 2018–2019 influenza season in Japan, enrolling healthy subjects (adults and children) whose family members tested positive for influenza via rapid influenza diagnostic testsDiagnosisThe test confirmed influenza infection (i.e., the “index patient”). In the study, participants were randomly assigned to receive a single dose of Xofluza (dose based on body weight) or placebo as a preventive measure against influenza. The primary endpoint of the study was to evaluate the proportion of participants who tested positive for influenza virus, had fever, and experienced one or more respiratory symptoms during the observation period from Day 1 to Day 10.

The results demonstrated that a single oral dose of Xofluza had a significant prophylactic effect against influenza infection in healthy subjects with household members diagnosed with influenza. Specifically, the proportion of subjects who developed influenza infection was significantly lower in the Xofluza group than in the placebo group (proportion of subjects developing viral influenza infection, fever, and other influenza-like symptoms during the 10-day observation period: 1.9% vs. 13.6%, p < 0.0001). The incidence of adverse events was 22.2% in the Xofluza group and 20.5% in the placebo group. No serious adverse events were reported in the Xofluza group during the study.

The detailed data of this study will be presented at future medical conferences.Meetingpublished. Sandra Horning, Chief Medical Officer and Global Head of Product Development at Roche, stated, “This positive Phase III study adds to the robust existing clinical data for Xofluza and confirms for the first time that single-dose treatment with Xofluza reduces the likelihood of developing influenza among other healthy subjects living in households with influenza-infected family members. Preventing influenza virus infection in healthy individuals can alleviate the disease burden on society as a whole, and we look forward to sharing these data with regulatory authorities worldwide.”

Xofluza is the first and only single-dose oral medication approved for the treatment of influenza, as well as the first novel anti-influenza drug with a new mechanism of action in nearly 20 years. Xofluza is also the only anti-influenza drug with a novel mechanism of action that has demonstrated efficacy in both otherwise healthy patients with influenza (CAPSTONE-1 study) and individuals at high risk for influenza-related complications (CAPSTONE-2 study).

Currently, Xofluza has been approved in Japan for the treatment of influenza A and B in children, adolescents, and adults, and in the United States for the treatment of acute, uncomplicated influenza in individuals aged 12 years and older. Furthermore, the United StatesFDARecently, a supplemental New Drug Application (sNDA) for Xofluza was accepted as a single-dose oral therapy for the treatment of individuals at high risk of influenza complications, including adults aged 65 years or older, or those withAsthma, patients with chronic lung disease, morbid obesity, or heart disease—for these individuals, influenza can be particularly severe or fatal.FDAA decision on whether to approve this indication is expected to be made on November 4, 2019.

Influenza is one of the most common yet serious infectious diseases, posing a significant threat to public health. Globally, annual epidemics result in 3 to 5 million cases of severe illness, millions of hospitalizations, and up to 650,000 deaths.

Xofluza is a first-in-class, single-dose oral medication with a novel anti-influenza mechanism of action distinct from other antiviral drugs on the market. As an endonuclease inhibitor, Xofluza is designed to inhibit the cap-dependent endonuclease in influenza viruses, an enzyme essential for viral replication. Xofluza is intended to combat influenza A and B viruses, including oseltamivir-resistant strains andAvian InfluenzaStrains (H7N9, H5N1). Tamiflu, developed by Gilead and globally commercialized by Roche, is a widely used oral anti-influenza medication. It typically requires multi-day consecutive administration, twice daily, with onset of action usually occurring within 72 hours.

Xofluza can eliminate the influenza virus within 24 hours, although some symptoms may persist for a longer duration. Xofluza requires only a single oral dose and is suitable for both adults and children, offering significant convenience and leading to a substantial improvement in patient adherence.

Xofluza was discovered by the Japanese pharmaceutical company Shionogi and is being jointly developed globally by Roche and Shionogi. Under the agreement, Roche holds global rights to the drug in all regions except Japan and Taiwan, China. (Bioon.com)

Original Source:Phase III study showed Xofluza (baloxavir marboxil) is effective at preventing influenza infection