Sanofi-Aventis’ vaccines subsidiary, Sanofi Pasteur, has failed to sort out quality control issues at a plant manufacturing its influenza vaccine Fluzone in the USA, according to the Food and Drug Administration.

The news immediately sparked fears that the USA could face a flu vaccine shortage in the 2006/7 season, as Sanofi Pasteur supplies around 50% of the USA’s total requirement for flu vaccine. However, Sanofi-Aventis insisted it would still be able to supply the 50 million doses it has been contracted to produce.

In 2004, a similar problem at Chiron’s manufacturing facility in Liverpool, UK, forced it to suspend supply of its Fluvirin vaccine, which was due to account for around 50% of US supplies. Other manufacturers including Sanofi-Aventis scrabbled to meet demand and this effort, coupled with a mild season, prevented any major shortages.

The problems at Chiron, now part of Novartis, opened the door for Sanofi to increase to market share but also allowed other companies, notably GlaxoSmithKline whose Fluarix product was recently approved in the USA, to start building positions in the US flu vaccine marketplace.

As with Chiron’s facility, the main compliance issue at Sanofi Pasteur’s plant in Swiftwater, Pennsylvania, relates to the risk of contamination in the sterile processing areas of the facility.

In a warning letter posted on the FDA’s website, the agency’s enforcement director, David Elder, said Sanofi Pasteur had been unable to ensure that its early-stage production materials were adequately segregated from materials used in late-stage sterile processing. There were also failures in adhering to sterile procedures and in quality control’s oversight of the process, said the letter.

The agency first looked at the problem after being alerted of sterility failures in some batches of Fluzone at the end of March. This led to an inspection of the plant in April and notice of compliance problems that the company has since failed to put right.

“At this time, the deficiencies noted in the inspection of Sanofi Pasteur’s Swiftwater manufacturing facility are not expected to significantly affect the availability of Fluzone for the 2006-7 flu season, but we continue to review the progress made by the company,” said the FDA. The plant will continue to make vaccine in the meantime.

Licenses cancer drug in $360m deal

Meanwhile, Sanofi-Aventis said it had licensed rights to an oral anticancer agent, S-1, from Japan’s Taiho Pharmaceutical. The drug consists of a prodrug of the widely-used cancer agent 5-FU, called tegafur, that is combined with two enzyme inhibitors to increase the amount of 5-FU released by the product but dampen down its gastrointestinal toxicity. S-1 has been on the market in Japan since 1999.

Sanofi-Aventis gets development and marketing rights to the product outside Japan and certain other Asian countries, in return for upfront and milestone payments valued at up to $360 million.