FASTER, PLEASE: Takeda’s Dengue Vaccine Shows Promise.

Takeda Pharmaceutical Co. TAK -0.59% released data from a large late-stage study Saturday showing that its experimental dengue vaccine was highly effective in preventing children from dengue illnesses and hospitalization overall from four types of the virus.

But the results suggested one potential concern, and the vaccine was slightly less effective overall than earlier data showed.

Effective measures to stop the spread of dengue are among the most urgent needs in global public health. Approximately 3.9 billion people in tropical regions of the world are at risk of infection with the virus, which is carried by an aggressive mosquito that teems in populated areas. An estimated 390 million people a year are infected with dengue. The World Health Organization listed dengue among 10 global health threats of concern in 2019.

But only one licensed vaccine—Dengvaxia from Sanofi SA, is available so far, and it has had safety problems. Takeda’s ongoing clinical trial of its TAK-003 vaccine, involving approximately 20,000 children between the ages of 4 and 16 in eight countries, is being closely watched.”

Effectiveness against one of the four types of dengue virus, however, is a bit subpar.