Wyeth (WYE. N) said that the deadline set for the review of its advanced vaccine, Prevnar 13, to prevent pneumococcal meningitis in infants and toddlers, has been extended by three months by the Food and Drug Administration, following the submission of additional data on the vaccine's formulation.

Wyeth's vaccine Prevnar 13, which is to be acquired by Pfizer(PFE. N), was decided to be reviewed on a priority basis within a span of six months instead of the standard
10 month review period.

Prevnar 13 is the most path breaking vaccine of the Wyeth series of experiments on drugs. It is even considered as being useful for future use in adults which could further boost the sales of this already hotselling vaccine. Wyeth is expecting to get approval to market Prevnar 13 for adults by 2010.

Prevnar 13 is formulated to provide prevention against 13 serotypes of streptococcus pneumoniae that can lead to a wide range of infections in infants and toddlers. The original vaccine, Prevnar was launched in 2000 and it protects from seven serotypes which covers about 80 percent of the potential infections. The new advanced vaccine will surpass the existing vaccine and 92 of the potential infections will be covered.

The delay in the review of Prevnar13 did not change the shares of WYE. N much whereas the shares of PFE. N remained unaffected.