The common vaccine-making process of blending flu virus strains appears to have been a factor in the nearly 10% adverse reaction rate to CSL's Fluvax among children last year. Intermingling of the strains after they were blended yielded "a surprise interaction" between the new flu strains required by the World Health Organization, according to a report on Fox Chicago.
"Studies indicate that the interaction between the strains used in the 2010 vaccine contributed to the reactions, but we are still working to understand the how and why," according to a CSL spokeswoman.
CSL Managing Director Brian McNamee said last month the company had replied to the FDA's objections and met with agency reps. "They are satisfied with our progress," he said, according to the Sydney Morning Herald, "but we accept this is a journey and we have to continue to update our systems and procedures." He added that CSL has been working "to improve our management systems from a compliance perspective. We are bringing in new systems and new staff."
- see the Fox story
- here's the Herald story
- and here's the FDA warning letter