Updated: 'Rubber contaminants' halt use of Moderna vaccine doses in Japan

Osaka, Japan – Takeda Pharmaceutical Co. Ltd has halted the supply of over half a million doses of the Moderna Covid-19 vaccine in Japan due to a contamination issue. 

In a 26 Aug statement, distributor Takeda said multiple vaccination centres in its home country had reported incidents of foreign matter being found in "unpunctured vials" of the vaccine

Moderna, it added, is currently conducting an "urgent investigation" into the foreign matter - being reported in Japanese media as rubber particles.

To date, there have been no reports of safety problems in relation to the batches, sourced from a supplier in Spain, according to Takeda.

Madrid-based Laboratorios Farmacéuticos ROVI SA (ROVI) said that it is currently investigating the matter, adding that “the origin of this manufacturing incident may be in one of ROVI’s manufacturing lines.” 

The company added that “detection of this particulate matter refers to certain vials of one product lot distributed exclusively in Japan,” and that it is working with Moderna and Takeda to determine the cause of the incident.

“ROVI is working in order to provide with all the information and assistance that may be needed to progress with the investigation,” the statement from CEO Juan López-Belmonte Encina concluded. 

In July 2020, ROVI announced an agreement for it to carry out large-scale, commercial fill-finish manufacturing of a Moderna mRNA COVID-19 vaccine at its facility in Madrid, for supply to markets outside of the US.  

The contract involved the procurement of a new production line and equipment for compounding, filling, automatic visual inspection and labeling to support production of hundreds of millions of vials containing vaccine doses.

While details of the contaminant partcles have yet to be confirmed, one focus for the investigations is likely to be on the rubber stoppers.

Typically made of butyl or halobutyl rubber, these components are essential to ensuring the safety and integrity of glass medicine vials.