An estimated 40,000 Army personnel based in the U.S. contract the virus each year, and Takeda conducted the phase 2b at a Navy training facility. Takeda framed the agreement as a way to enable it to focus on vaccines against dengue, COVID-19, pandemic influenza and Zika. Regulatory submissions for the dengue vaccine began earlier this year. The creation of HilleVax comes two years after Takeda teamed up with Frazier to found another biotech. In the earlier deal, the partners created Phathom Pharmaceuticals to develop vonoprazan and other treatments for gastrointestinal diseases and disorders. Both spin outs gave Takeda a way to advance candidates, and potentially profit from their success, without committing internal resources.