Japan on Thursday suspended the use of 1.63 million doses shipped to 863 vaccination centres nationwide, more than a week after the domestic distributor, Takeda Pharmaceutical, received reports of contaminants in some vials
Moderna will increase its deliveries to 1.33 million doses a week in July from 733,000 previously expected, raising the figure to 2.57 million a week in August and 2.95 million a week in September, the ministry said.
Moderna said an initial analysis of a study in adolescents aged 12-17 years showed an efficacy rate of 96% for its vaccine.
The company has also been working on a new version that could extend the time the vaccine can be stored in refrigerator temperatures, making it easier to distribute, especially in lower-income countries.
The trial, backed by the National Institutes of Health (NIH), is designed to determine if the vaccine, mRNA-1273, can prevent coronavirus infection, limit virus in the nose, and reduce transmission from vaccinated individuals to their close contacts.
The Prevent COVID U study, funded by the National Institute of Allergy and Infectious Diseases (NIAID), will monitor about 12,000 young adults across 20 universities over a five-month period.