An advisory committee to the U.S. Food and Drug Administration (FDA) has voted unanimously to recommend approval of Gardasil®, a vaccine that has been proven to be safe and effective for the prevention of cervical cancer and pre-cancerous lesions of the cervix, vulva, and vagina caused by two common strains of the human papilloma virus (HPV). If the FDA approves the vaccine based on the recommendations of the advisory committee, Gardasil will be the first cervical cancer vaccine approved in the U.S.

Approximately 20 million people are infected with HPV in the U.S., and for most people, HPV goes away on its own. In some, however, certain high-risk types of HPV, if unrecognized and untreated, can lead to cervical, vaginal, vulvar, and anal cancers. Cervical cancer is the second most common cause of cancer death in women worldwide, resulting in nearly a half-million diagnoses and 240,000 deaths each year. In addition, certain low-risk types of HPV cause genital warts and can lead to abnormal Pap results. Approximately 1 million cases of genital warts occur each year in the United States and an estimated 32 million cases occur worldwide. Additionally, there are an estimated 4.7 million abnormal Pap 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.

Gardasil, developed by Merck & Co., is a cervical cancer vaccine designed to protect against four types of HPV: types 6, 11, 16 and 18. HPV types 16 and 18 account for an estimated 70% of cervical cancer cases and can lead to vulvar and vaginal cancers. HPV types 6 and 11 account for an estimated 90% of genital wart cases and can cause abnormal Pap tests and low-grade cervical abnormalities.

Results from Merck’s clinical trials, presented to the FDA’s Vaccines and Related Biological Products Advisory Committee, evaluated the safety and efficacy of Gardasil in more than 27,000 females and males from 33 countries around the world. In the key efficacy studies involving 20,887 women aged 16 to 26, Gardasil prevented 100% of cervical, vaginal and vulvar pre-cancers caused by HPV types 16 and 18, prevented 95.2% of cervical lesions caused by HPV types 6, 11, 16 and 18, and prevented 99.1% of external genital lesions, including genital warts, caused by HPV types 6, 11, 16 and 18.

The safety and effectiveness of Gardasil in HIV-positive people have not been determined. Similarly, the effectiveness of Gardasil as a preventive vaccine against cancer and pre-cancerous lesions of the anus, in HIV-negative or HIV-positive men or women, has not been determined.

The Committee’s guidance will be considered by the FDA in its final review of Merck’s approval application, which should be completed by June 8, 2006. Information about the vaccine will also need to be reviewed by the U.S. Centers for Disease Control’s Advisory Committee on Immunization Practices (ACIP), which will make recommendations regarding the actual use of the vaccine in the United States.

Studies indicate that approximately 40% of HPV infections occur within 16 months of first sexual activity. In turn, it is expected that ACIP will recommend Gardasil for school-aged children in the hope of reaching them before they have sex.