People may soon have another option when treating the flu. And, this new single-dose medicine could work in just 24 hours.

There has not been a new FDA-approved flu medication for many years.

This is important since rare sporadic instances of oseltamivir-resistant and peramivir-resistant influenza A(H1N1)pdm09 viruses and oseltamivir-resistant influenza A(H3N2) viruses have been detected worldwide, said the Centers for Disease Prevention and Control (CDC) in the February Week 5 update.

The CDC recommends antiviral treatment as early as possible for people with confirmed or suspected influenza.

A Japanese pharmaceutical manufacturer completed a phase 3 clinical trial in January 2018, for a medication that is reported to kill the flu virus, within one day.

This late-stage clinical trial on Japanese and American flu patients found that for the people who took, a single dose of Baloxavir marboxil (S-033447) for treatment of influenza A and B, eliminated the flu virus ‘shedding’ in just 24 hours.

That is a much quicker response time than Tamiflu (oseltamivir), a leading flu medicine.

But, this medication will not be available this year in the USA.

Which means, the best defense against influenza remains vaccination.

Baloxavir marboxil, known clinically as S-033447, and produced by Shionogi & Co., Ltd., is a novel small molecule inhibitor of cap-dependent endonuclease that is essential for influenza virus transcription and replication.

This clinical study was a phase 3, multicenter, randomized, double-blind study of a single dose S-033188 Baloxavir Marboxil, compared with placebo or Oseltamivir 75 mg, twice daily for 5 days.

The median time to cessation of viral shedding was 24 hours in patients treated with S-033188, compared to 72 hours in those treated with oseltamivir and 96 hours for placebo.

During October 2017, Shionogi & Co., Ltd. announced the clinical results of the S-033188 Phase 3 study at IDWeek™ in San Diego. This presentation’s highlights included the following:

Significant improvement in time to alleviation of symptoms (TTAS) compared with placebo. S-033188 demonstrated superiority to placebo in TTAS; the median TTAS was 53.7 hours in the S-033188 group, compared to 80.2 hours in the placebo group (p<0.0001).

TTAS was similar between S-033188 and oseltamivir groups.

Significant improvement compared with placebo or oseltamivir for important virological endpoints. The percentage of patients determined to be positive for influenza virus titer was significantly lower in the S-033188 group compared to the oseltamivir group at one, two and four days from the start of treatment.

In addition, the time to cessation of viral shedding was significantly decreased in the S-033188 compared with the oseltamivir group.

The researchers involved in this clinical trial were paid by the manufacturer, Shionogi & Co.

No pricing or USA released date was disclosed.

Additional CDC information on recommendations for treatment and chemoprophylaxis of influenza virus infection with antiviral agents is available here.