Moderna Inc and it’s Japanese distribution company, Takeda Pharmaceutical Co Ltd on Wednesday said they are working with Japanese authorities to recall three batches of Covid-19 vaccine after an investigation found stainless steel contaminants in some vials.
Previously, Japanese authorities had suspended the use of batches of Moderna shots containing 1.63 million doses and a further 1 million doses respectively due to contamination reports. According to the Japanese health ministry, two men aged 38 and 30 died in August within days of receiving their second Moderna doses from the suspended batches.
Japan’s health ministry said on Wednesday, based on information from the company’s investigation, that it did not believe the particles of stainless steel pose any additional health risk. Moderna said the stainless steel contamination probably occurred during production.
Moderna conducted their investigation with Takeda and Rovi at the manufacturing plant where the contamination occurred and said in a joint statement with Takeda that the most probable cause of contamination was related to friction between the two pieces of metal in the machinery that puts stoppers on the vials. The material was confirmed to be stainless steel.
Their joint statement also said,
“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”.
About 500,000 people have received the shots from the suspended Moderna batches according to Japan’s vaccine minister Taro Kono but Moderna said it cannot confirm how many doses were distributed from the batches.