‘Human Error’ Caused Contamination Of 1.63M Moderna COVID Vaccine Doses In Japan

Following the suspension of 1.63 million doses of Moderna’s (MRNA) COVID vaccine in Japan due to metal contamination, Takeda Pharmaceutical, the import and distribution arm of the shot in Japan for Moderna, said the contaminants were caused by “human error.”

Takeda, along with Moderna, said in a report obtained by Reuters that the contamination issue was caused by “incorrect assembly and was due to human error specific to visually misjudging the required 1 mm gap between the star-wheel and the stopper" of the machinery that is used to put the tops of the vaccine on the vials.

Back in August, Japanese officials suspended the 1.63 million doses of the Moderna vaccine after metal fragments were noticed in the vials. An investigation was conducted by Moderna and Takeda as well as with the Spanish manufacturer of the vaccine Rovi, where the contamination occurred in the Japanese shots.

According to the report, a total of five sequential lots of the Moderna vaccine produced by Rovi from June 27 to July 3 were investigated. Three lots shipped to Japan and were then recalled after the metal particles were discovered to be stainless steel in 39 vials, Reuters reported.

A fourth lot failed inspection on July 2, and a fifth lot was held back by Rovi, with lots 4 and 5 reported to Moderna, Takeda, and Japan’s health ministry, Reuters said. But the first three lots were released because they “had passed inspection and were not considered to be impacted,” the report indicated.

The report also said that incorrect set-up “led to the issue persisting throughout the series of five batches,” which was corrected through improved operating procedures and a new precision tool to prevent the issue from recurring.

Moderna, Takeda, and Japanese health officials have said that the metal contaminants did not pose any health risks.

As many as 180,000 people may have been inoculated with the contaminated doses of the Moderna COVID vaccines before the metal contamination was discovered and recalled, Kyodo News reported in August.

As of Friday at 11:40 a.m. EST, shares of Moderna were trading at $338.05, down $46.81 or 12.16%.