Pfizer vaccine trial success signals breakthrough in pandemic battle

FILE PHOTO: A sign is pictured outside Pfizer Headquarters in the Manhattan borough of New York City, New York, U.S., July 22, 2020. REUTERS/Carlo Allegri

(Reuters) - Pfizer Inc's experimental COVID-19 vaccine is more than 90% effective based on initial trial results, the drugmaker said on Monday, a major victory in the war against a virus that has killed over a million people and battered the world's economy.

Scientists, public health officials and investors welcomed the first successful interim data from a large-scale clinical test as a watershed moment that could help turn the tide of the pandemic if the full trial results pan out. However, mass roll-outs, which needs regulatory approval, will not happen this year and several vaccines are seen as necessary to meet massive global needs.