In the United States, approximately 10,000 women are diagnosed with cervical cancer every year, and an average of 10 women die each day from the disease.

The FDA approved Gardasil for the prevention of cervical cancer; cervical pre-cancers [cervical intraepithelial neoplasia (CIN) 2/3 and adenocarcinoma in situ (AIS)]; vulvar pre-cancers [vulvar intraepithelial neoplasia (VIN) 2/3]; and vaginal pre-cancers [vaginal intraepithelial neoplasia (VaIN) 2/3)] caused by HPV types 16 and 18. The vaccine is also approved for the prevention of genital warts and low-grade cervical lesions (CIN 1) caused by HPV types 6, 11, 16 and 18. It is approved for nine to 26-year-old girls and women.

"Bringing forward this life-saving scientific advance is yet another testament to Merck’s long-standing mission to research and develop novel vaccines and medicines that can greatly improve public health," said Richard T. Clark, chief executive officer and president, Merck & Co., Inc.

Gardasil is designed to prevent the majority of HPV-related clinical diseases. HPV types 16 and 18 account for approximately 70 percent of cases of cervical cancer, AIS (non-invasive cervical cancer), CIN 3, VIN 2/3 and VaIN 2/3, account for 50 percent of CIN 2 lesions. HPV 6 and 11 cause approximately 90 percent of genital wart cases. These four types of HPV also cause approximately 35 to 50 percent of all low-grade cervical, vaginal and vulvar lesions (CIN 1, VIN 1 and VaIN 1).

These are an estimated 4.7 million abnormal Pep results that require follow-up each year in the United States. At least 3 million of these results are caused by some type of HPV. All four types cause abormal Pap test results; the lesions caused by types 6 and 11 are clinically indistinguishable from pre-cancerous lesions caused by types 16 and 18.

"This is a major health breakthrough – the first vaccine specifically designed to prevent cancer – and is approved to prevent not only cervical cancer but also genital warts," said Kevin Ault, MD, associate professor, Department of Gynecology and Obstetrics, Emory University School of Medicine, and clinical study investigator for Gardasil.

"Use of Gardasil can help significantly reduce the human and economic burden of cervical cancer, precancerous or low-grade lesions and genital warts caused by HPV 6, 11, 16 and 18 in the United States, and the rest of the world, in this generation and future generations."

In clinical studies, the vaccine prevented 100 percent of HPV 16- and 18- related cervical cancer in women not previously exposed to the related HPV types

Its efficacy, which includes results from an HPV-16 prototype, was evaluated in four placebo-controlled, double-blind, randomized Phase II and Phase III clinical studies. Together, the Phase II and III studies evaluated 20,541 women aged 16 to 26 years. Study participants were followed for up to five years after enrollment.

The studies’ primary analyses were conducted in women who received all three vaccinations within one year of enrollment, did not have major deviations from the study protocol and were naive to the relevant HPV type(s) prior to dose one and through one month analyses and measured starting after the Month 7 visit.

The studies also showed that administration of Gardasil to women who are already infected with one or more vaccine related HPV types prior to vaccination protects from clinical disease caused by the remaining vaccine types but may not alter the course of an infection that is already present.