Cap-snatching endonuclease inhibitor

Influenza Antiviral



Annually, influenza affects up to 50 million individuals and causes about 290 to 650 thousand respiratory deaths.

Despite the availability of the flu vaccine, vaccination rates, especially in developed countries, remain sub-optimal. Vaccination rate varies by country, from 27% in the Germany to 47% in the US. Additionally, US CDC report estimated the vaccine effectiveness about 50% for seasonal flu during 2004~2018. All these factors make influenza high on the list of indications with high unmet medical need.

Current influenza treatments such as oseltamivir must be taken within 48 hours of onset of symptoms. Not with standing its effectiveness, Oseltamivir has been downgraded in the World Health Organization’s list of essential medicines since there was no evidence of reducing complications, hospital admissions, or mortality.
  • Indications in Development
  • Influenza A
  • Influenza B
  • Avian Influenza H7N9


  • Act on cap-snatching mechanism and block influenza virus replication and transmission.
  • Inhibit influenza viruses A, B and avian influenza virus H7N9 effectively.
  • Effective even given in 72 hours after the onset of symptoms.
  • With potential of single dose treatment for influenza infection.
  • More safe than other drugs in same class


Tamiflu’s 2019 full-year sales of USD 388 million were flat compared with 2018, its U.S. sales plummeted 75% to merely USD 44.3 million.

The market size of influenza antiviral in China has doubled in recent years. The sales of Oseltamivir had surpassed RMB 6 billion in 2019 and is projected to exceed RMB 10 billion in 2020.

WHO downgraded oseltamivir on drug list in terms of less cost effectiveness in 2017.

In 2018, Baloxavir Marboxil for the treatment of influenza A and B launched in Japan and the US.


  • Submitted pre-IND meeting to China NMPA in 2019 and filed IND in 2020.
  • IND filings to major influenza antiviral markets such as China, US, Japan and Korea from 2020.
  • Acquired first patent in the U.S. in 2020.
  • Received TG-1000 Clinical Trial Authorization in the U.S. and mainland China.
  • Completed phase I study and initiated phase II trial.