The Italian Medicines Agency (AIFA) lifted a temporary hold on the use of Novartis seasonal influenza vaccines in Italy last week, after additional Novartis data and an AIFA independent assessment affirmed the vaccines’ safety and efficacy, said Novartis in a Nov. 9, 2012 press release.

The vaccines were pulled from use in Italy on Oct. 24, 2012, following Novartis’ report of higher than usual levels of protein aggregates observed in one batch of seasonal influenza vaccine, which was not released for use. The aggregates are formed by proteins essential to the vaccine, can naturally occur in very small quantities, and typically dissolve when shaken.

Italy’s action led to similar precautionary holds in other countries. Health Canada voluntarily suspended distribution of the vaccines in Canada, but released the products the following week after reviewing safety information, according to an Oct. 31, 2012 press release from Health Canada. The agency noted that clumping of the kind observed is common in vaccines and has had no observed impact on safety or effectiveness.

Distribution also resumed in Switzerland on Oct. 31 and in Singapore on Nov. 2. The products are not marketed in the US. Within the EU, Italy is the regulatory reference country for the products, and Novartis plans to work with other countries to lift remaining precautionary measures and resume supply as soon as possible.

“Novartis welcomes this positive development with the Italian authorities. Patient safety is our highest priority and we have always remained confident in the quality of our vaccines,” said Andrin Oswald, division head of Novartis Vaccines and Diagnostics, in the press release. “The safety and efficacy of Agrippal and Fluad are supported by extensive clinical and surveillance data, including more than one million doses administered this season.”