The recent first global approval of baloxavir marboxil has been reviewed in detail in the First Global Approval report in Adis’ journal Drugs, based on the development milestones tracked in AdisInsight..
Japan was first country to approve baloxavir marboxil (XOFLUZA™) in February 2018, under Sakigake fast track review. The agent is being jointly developed by Shionogi and Roche and was approved for the treatment of influenza types A and B in paediatric and adult patients. Baloxavir Marboxil is dispensed as a convenient oral tablet; it is a cap-dependent endonuclease inhibitor that blocks influenza virus proliferation by inhibiting the initiation of mRNA synthesis.
The recommended single oral dose of baloxavir marboxil, taken as soon as possible after the first onset of symptoms, is expected to improve compliance. It is believed that the improved compliance and the novel mechanism of action will prevent resistance development, which is a growing concern regarding other already-marketed antiviral agents used to treat influenza outbreaks. 
According to one source, Daniel O’Day, head of Pharma Unit, Roche, explained that “…it’s one pill once, versus a course of therapy, so particularly for pandemic planning, this could be an advantage. You don’t have the potential resistance that comes with not completing your course of therapy.”
In the CAPSTONE-1 phase III trial the period of viral shedding (i.e. the contagious period) was significantly shorter with baloxavir marboxil (median time to shedding cessation = 24h) than with osteltamivir, or placebo (72 and 96 hours, respectively).
Baloxavir marboxil is also under phase III development in the US and Canada. 
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