Drug maker Merck & Co. announced Wednesday that the U.S. Food and Drug Administration would consider whether to expand use of Gardasil, intended to prevent cervical cancer to women aged 27 to 45.

Gardasil is currently approved in the United States for use in girls and women aged 9 through 26 to block four types of human papilloma virus, which can cause cervical cancer and genital warts.

The priority review granted by the FDA to Gardasil means that the health agency is expected to make its decision on the marketing application within 6 months, rather than within the agency’s typical 10-month review period.

Cervical cancer is the second most common cause of cancer death in women worldwide, resulting in nearly a half-million diagnoses and 280,000 deaths each year. In 2007, there were an estimated 11,000 new cases of cervical cancer and 3,600 deaths in the U.S., Merck said in a news release.

About 6.2 million men and women become infected with HPV every year in the U.S. and approximately 20 million people are currently infected. Experts warn that even though the vaccine is purely preventive; it does not cure an existing HPV infection, but can prevent future infections. That is why is recommended that girls get the vaccine before they are sexually active.

Currently Gardasil is the only cervical cancer vaccine on the market. It has racked up about $1 billion in sales since its June 2006 U.S. launch. GlaxoSmithKline PLC is waiting approval of its own vaccine, Cervarix.