(McClatchy-Tribune Information Services) -- The largest-ever trial for a cervical cancer vaccine shows that the drug Cervarix protects women from five of the most common cancercausing viruses, a University of New Mexico researcher said Tuesday.

The three-year study of more than 18,000 girls and women found that the drug offers protection from up to 85 percent of cervical cancers, said Cosette Wheeler, a UNM professor of molecular genetics and microbiology.

The study, published Tuesday in the medical journal The Lancet, shows that Cervarix offers protection against three cancer-causing viruses in addition to the two for which the drug was designed, said Wheeler, an author of the study.

Human papillomavirus, or HPV, is the most common type of sexually transmitted infection, according to the Centers for Disease Control and Prevention. More than 40 varieties of HPV can infect male and female genitals.

Two HPV varieties, HPV 16 and 18, account for more than 70 percent of cervical cancers. About 12,000 U.S. women are diagnosed with cervical cancer each year.

Cervarix, manufactured by drugmaker GlaxoSmithKline, was designed specifically to offer protection against HPV 16 and 18, Wheeler said.

But the study found that Cervarix also offers " crossprotection" against HPV 31, 33 and 45, which are closely related to HPV 16 and 18, she said. HPV 31, 33 and 45 together account for 11 percent to 16 percent of cervical cancers, she said.

Cervarix has been approved for use in more than 90 countries but awaits approval in the U.S. by the Food and Drug Administration.

Another HPV vaccine, Gardasil, has been approved for use in the United States. It is given in three shots over six months, according to the CDC. The vaccine is routinely recommended for 11- and 12-yearold girls.

Gardasil offers protection against HPV 16 and 18 and some protection against HPV 31, said Wheeler, who also did research that led to the development of Gardasil.

Copyright (C) 2009, Albuquerque Journal, N.M.