Japan's health ministry Tuesday approved the use of a COVID-19 vaccine developed by U.S. biotechnology firm Novavax Inc., with deliveries of the drug to local governments expected to start in late May, and shots might also begin that month.
The approval by the Ministry of Health, Labor and Welfare marks the fourth vaccine to be greenlit for use in Japan and will be produced domestically by medical giant Takeda Pharmaceutical Co., which has been given the technology to manufacture the drug.
Novavax's vaccine will be the first protein-based one, intended for patients who could not use existing vaccines due to risks such as allergies.
"We have purchased the shots to increase the stability and diversity of the vaccine supply," health minister Shigeyuki Goto said at a press conference after the government had secured 150 million doses.
The vaccine can be administered to people aged 18 or older in two shots spaced three weeks apart. It can also be used as a booster shot after six months.
Whether the vaccine can be used for mixing and matching booster shots will be decided by an internal subcommittee in the near future, the health ministry said.
Overseas clinical trials conducted before the Omicron variant became widespread showed that the vaccine was around 90 percent effective in preventing the onset of symptoms after the first and second shots were administered.
After the third dose, it was also shown to improve the value of neutralizing antibodies that prevent the virus from entering cells in the body.
Although weaker against the Omicron variant, the vaccine also has "a certain effect" on the mutant strain, the health ministry said.
In clinical trials conducted in the United States and elsewhere, 44.5 percent of patients who have received two shots reported side effects such as headaches, 38.9 percent said they felt fatigued, and 48.1 percent said they experienced muscle soreness.
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