The U.S. FDA has approved Pfizer’s best-selling vaccine Prevnar 13 for expanded use in adults 50 and older to prevent pneumonia, meningitis and other diseases cause by pneumococcus bacteria.

Prevnar 13Pfizer said in an announcement that the approval of Prevnar 13 for these adults offers the potential to contribute to the health of millions of aging Americans.

The Prevnar 13 vaccine, designed to prevent 13 forms of a bacterium called  pneumococcus, had been already approved for children in the United States. It is also cleared for use in adults aged 50 and older by regulators from the European Union, Australia, Bolivia, Colombia, Ecuador, Thailand and the Philippines.

There are about 300,000 patients in the United States in that older age group are hospitalized each year because of pneumococcal pneumonia, according to the FDA.

Dr. Karen Midthun, director of FDA’s Center for Biologics Evaluation and Research, said “Pneumococcal disease is a substantial cause of illness and death. Today’s approval provides an additional vaccine for preventing pneumococcal pneumonia and invasive disease in this age group.”

Prevnar 13 was evaluated by the FDA  under an accelerated approval process. In November, the vaccine won the support of an FDA advisory committe , with a vote of 14-1 in favour of the approval of Prevnar 13 as a safe and effective vaccine to prevent the bacterial infections in adults.

Before the approval of Prevnar 13, Merck’s Pneumovax, a vaccine approved almost 30 years ago, is the  only product cleared in the United States for pneumococcal bacteria infection for older adults. According to the FDA,  Merck’s vaccine is effective against invasive pneumonia, but was not shown to have an effect on the more common  pneumococcal pneumonia. 

The New York-based drug maker said the Prevnar 13 vaccine that use new conjugates technology leads to a stronger and longer-lasting immune response. The vaccine is already one of Pfizer’s biggest earner with about $3.7 billion sales globally last year. The expanded use in adults could generate more than $1.5 billion in annual sales for the company.

Pfizer will be doing a further study to confirm Prevnar 13 can actually prevent pneumococcal pneumonia in adults, not just cause the body’s immune response. The confirmatory trial is expected to complete in 2013.