By Khushi Mandowara and Mariam ESunny
(Reuters) - A panel of outside advisers to the U.S. health regulator on Tuesday recommended Pfizer Inc (NYSE:PFE)'s respiratory syncytial virus (RSV) vaccine, bringing it closer to becoming one of the first approved RSV shots for older adults in the United States.
The Food and Drug Administration's (FDA) advisory committee voted 7-4 in favor of the vaccine, saying data from the company's study established that the shot was effective and safe in preventing lower respiratory tract disease caused by RSV in people aged 60 years and older. One member abstained during voting.
GSK, which is another forerunner in a crowded race to develop the first RSV vaccine, will face scrutiny from a panel of experts to the FDA on Wednesday.
Companies such as Johnson & Johnson (NYSE:JNJ), Moderna (NASDAQ:MRNA) Inc and Merck are also looming on the horizon.
While panelists backed Pfizer's vaccine, concerns were voiced over insufficient efficacy data in the company's study for adults 80 and above, who need the vaccine the most, and suggested a need for detailed post-marketing safety surveillance to address issue of any serious adverse event.
"The population where the vaccine is going to potentially have the biggest impact is less represented in this study," said Hana Sahly, one of the 12 FDA panelists.
The first approved vaccines for the virus, which kills roughly 14,000 older adults in the United States annually, could help the firms gain a foothold in a market estimated at $5 billion to $10 billion, according to analysts.
The FDA is scheduled to decide on the vaccines by May, and typically follows the recommendations of its independent panel of experts.
Pfizer's vaccine was 66.7% effective in preventing RSV-related lower respiratory tract illness with over two symptoms, while GSK's vaccine was 82.6% effective in preventing lower respiratory tract disease in people aged 60 and over.