JAPAN – Japan has suspended the use of 1.63 million doses of Moderna Inc’s COVID-19 vaccine, more than a week after the domestic distributor received reports of contaminants in some vials.
Both Japan and Moderna said no safety or efficacy issues had been identified and the suspension was just a precaution.
“Moderna confirms having been notified of cases of particulate matter being seen in drug product vials of its COVID-19 vaccine,” the U.S. vaccine maker said in a statement, adding it put the lot in question and two adjacent lots on hold.
“The company is investigating the reports and remains committed to working expeditiously with its partner, Takeda, and regulators to address this,” it added, referring to Japan’s Takeda Pharmaceutical, which distributes the vaccine in the country.
Moderna said the contamination could be due to a manufacturing issue in one of the production lines at its contract manufacturing site in Spain.
A spokesperson for the company added that the affected production batch, plus two more batches held back out of caution because they were processed before and after the affected batches, were meant for distribution only in Japan.
Spanish pharma company Rovi, which bottles or “fills and finishes” Moderna vaccines for markets other than the United States, said it is investigating possible contamination of Moderna doses and the issue appeared to be limited to a few batches bound for Japan.
The suspension is a fresh setback for Moderna, whose partners had production delays last month that disrupted supplies to countries including South Korea.
Japan’s defense ministry, which operates a mass vaccination site in Osaka, said shots from the lot in question, which contains 565,400 doses, had been used in the western prefecture between August 6 and August 20, but it did not say how many people were affected.
The decision to suspend use of the Moderna shots comes at an awkward time for Prime Minister Yoshihide Suga, whose government was criticized over a slow rollout in the vaccine campaign earlier in the year.
Japan is battling its worst wave of infections, driven by the Delta variant, with new daily infections exceeding 25,000 this month for the first time.
It has inoculated 54% of its population with at least one dose and fully vaccinated 43%, according to a Reuters vaccine tracker.