The results of a major clinical trial involving 12,167 women shows Gardasil, a genetically-engineered vaccine by Merck & Co., was 100 percent effective in preventing persistent infection with the two major strains of the human papillomavirus (HPV) that account for 70 percent of cervical cancer cases.
That is exciting news for Kevin Ault, MD, associate professor of obstetrics and gynecology at the Emory University School of Medicine who practices at Grady Memorial Hospital and Emory University Hospital. Dr. Ault served as a clinical trials investigator for the vaccine during his tenure at University of Iowa School of Medicine. He says news of the vaccine's effectiveness is wonderful news for women.
"As far as a cancer vaccine goes, this is the best we have," says Dr. Ault, who has spent much of his career researching the HPV vaccine. "In four or five generations we've gone from cervical cancer being the most common cause of cancer death in the United States for women to being a vaccine-preventable disease. That's a really remarkable story if you trace this research over the last 50 to 60 years."
The final-stage study of Gardasil, which was funded by Merck & Co., included 12,167 women ages 16 to 26 in the United States and 12 other countries who were not infected with HPV 16 or 18. Participants were randomized to receive a three-dose regimen of either Gardasil or placebo at day one, month two, and month six. The primary analysis of the trial showed that women who received the vaccine were followed for 17 months after completion of the regimen. In this group, Gardasil prevented 100 percent of cases of high-grade pre-cancer and non-invasive cancer associated with HPV types 16 and 18.
Dr. Ault discussed an abstract that details the vaccine study at the recent Infectious Diseases Society of America meeting in San Francisco, California.
According to the Centers for Disease Control and Prevention (CDC), approximately 630 million people are infected with HPV worldwide, and a significant majority of women -- 80 percent -- will become infected by age 50. HPV infection is most common among young adults between the ages of 18 and 28. Nearly half a million cases of cervical cancer are diagnosed each year worldwide, and more than 250,000 women die each year due to cervical cancer. Cervical cancer is the second most common cancer in women worldwide after breast cancer, and in developing countries, it is the leading cause of death by cancer.