REFILE-Wyeth says Prevnar could ease scourges of elderly

(Corrects spelling in paragraph 6)

* Wyeth says improved Prevnar vaccine may be pneumonia breakthrough in elderly

* Says new vaccine a weapon against bloodstream infections

* Says separate new meningitis vaccine could fill protection gap

By Ransdell Pierson

NEW YORK, June 30 (Reuters) - A new form of Wyeth's WYE.N lucrative Prevnar vaccine being developed for adults could be a breakthrough product by helping prevent pneumonia and dangerous bloodstream infections among the elderly, according to top Wyeth vaccine executives.

Like the $2.5 billion-a-year product already approved for infants and toddlers, it is designed to prevent infections with a bacterium called streptococcus pneumoniae (pneumococcus) that can cause a wide array of diseases, ranging from ear infections to fatal meningitis.

"Pneumonia caused by the pneumococcal organism is one of the most significant causes of death in older individuals and its incidence begins to increase when one is roughly 50 years old, and increases rapidly thereafter" as the immune system weakens, Dr. Emilio Emini, Wyeth's head of vaccine research and development, said in an interview.

The mortality rate for adults with the form of pneumonia averages 10 percent to 20 percent even in developed countries, according to Wyeth, and can exceed 50 percent in high-risk patients.