Doctors may have a new treatment for swine flu that's already on pharmacy shelves — cholesterol-lowering statin drugs like Lipitor and Zocor.

Researchers reported today that people who were already on these drugs when they caught seasonal flu and had to be hospitalized were twice as likely to survive than those not on such medicines.

That's not proof that statins are a cure for flu. More study is under way to see if the drugs might be a good treatment. The study, presented at a medical meeting in Philadelphia, involved 2,800 patients during the 2007-08 flu season.

"It's very promising," said the study's leader, Dr. Ann Thomas of the Oregon Public Health Division.

Statins have long been known to reduce inflammation along with cholesterol. Much of the damage that flu causes, whether it's seasonal or the new H1N1 virus, is from inflammation, an overreaction by the immune system as it fights the virus.

Previous studies also have found that statins may help people survive pneumonia and serious bacterial bloodstream infections.