A view on regulatory aspects of live viral vaccine safety.

Regulatory requirements on live viral vaccines take into consideration their value in the improvement of public health in countries that have used them in large vaccination campaigns. However, since they have also been involved in clinical accidents, a careful assessment of their safety is necessary to establish the risk-benefit balance. From this point of view, live recombinant vaccines represent a new category of products and their future use in the field should be preceded by scientific debate concerning their safety and potency.