LONDON–GSK PLC said its experimental vaccine against respiratory syncytial virus sharply reduced the risk of disease in a key trial, paving the way for a contest with Pfizer Inc. in what the companies expect to be a lucrative market.
Respiratory syncytial virus, or RSV, is a common virus that proves deadly for some 14,000 older adults in the U.S. every year. Although identified decades ago, there are no approved vaccines against the virus, which in most people causes cold-like symptoms but can lead to more severe disease affecting the lungs in young babies and older adults. Now, two shots are jostling to be the first to a market that analysts estimate could be worth around $5 billion a year.
