After suspending the use of 1.63 million doses of the Moderna COVID-19 vaccine over contamination concerns last week, Japan is now recalling those doses, Moderna Inc. and its Japanese partner, Takeda Pharmaceutical Co. Ltd. said Wednesday.
Last week, some vials of the vaccine were found to be contaminated with stainless steel.
Japanese officials said Wednesday that they did not think the stainless steel particles posed a health risk, while Moderna said the contamination was probably caused by pieces of metal rubbing together in the machinery that puts stops on the vials.
"Stainless steel is routinely used in heart valves, joint replacements and metal sutures and staples. As such, it is not expected that injection of the particles identified in these lots in Japan would result in increased medical risk," Takeda and Moderna said in a joint statement.
According to Taro Kono, the Japanese minister overseeing vaccinations, around 500,000 people received shots from the suspended Moderna batches.
The focus on the contaminated doses was heightened after two men died within days of receiving second doses from the contaminated batches.
While their deaths are still being investigated, Moderna and Takeda said there was no evidence the vaccine played a role in their deaths.
"The relationship is currently considered to be coincidental," the companies said in the statement.
(Some information in this report comes from Reuters.)