The vaccine is designed to prevent diphtheria, pertussis or whooping cough, polio, tetanus and Haemophilus influenzae type b. It is sold in nine countries including Canada. A spokesperson for Sanofi said that the delay was nothing to do with the vaccine itself, and said that it was a technical matter.
The FDA had asked Sanofi earlier in the year about the way it is conducting analysis in its new lab in the US, after moving production from Canada.