(Adds details on tests, safety findings)

Oct 29 (Reuters) - Pfizer Inc has won U.S. approval for its Trumenba vaccine against meningitis B, a potentially deadly bacterial disease that has recently caused outbreaks on college campuses, the U.S. Food and Drug Administration said on Wednesday.

Trumenba, approved in individuals 10 to 25 years of age, has been considered one of the most important products in Pfizer's drug pipeline. It was granted accelerated approval following tests in 2,800 adolescents in the United States and Europe.

After receiving three doses of the vaccine, 82 percent had antibodies in their blood that killed four different strains of meningtitis B that typically cause disease in the United States, compared with fewer than 1 percent before vaccination.

The most common side effects associated with the vaccine included inflammation at the site of the injection, headache and diarrhea.

It is the first approved U.S. vaccine that prevents invasive disease caused by serogroup B of the bacterium Neisseria meningitidis. It causes disease in an estimated 20,000 to 80,000 people a year globally, according to Pfizer. The FDA estimates serogroup B causes about 160 U.S. meningitis infections annually in the United States.

The agency noted that other vaccines are already approved in the United States to prevent infections with four other serogroups of the bacterium: A, C, Y and W.

Meningitis can be treated with antibiotics, but 10 to 15 percent of patients die and up to 19 percent of survivors have long term disabilities, including brain damage and limb amputations. Vaccination is deemed the best way to prevent the disease.

Pfizer and Swiss drugmaker Novartis had both won the FDA's coveted "breakthrough therapy" designation for their rival meningitis B vaccines and were racing for the first FDA approval.

Novartis' vaccine, called Bexsero, is already sold in dozens of countries. Although not yet approved in the United States, it was provided last winter to students at Princeton University and the University of California, Santa Barbara, in response to local meningitis B outbreaks on both campuses.

Bexsero could soon belong to British drugmaker GlaxoSmithKline because of a deal reached in April, under which Novartis will sell all its non-influenza vaccines to GSK for $7.1 billion. The deal is expected to close next year.

(Reporting by Ransdell Pierson; Editing by Marguerita Choy)