Safety and Immunogenicity Study of an Additional Dose of HPV Vaccine (580299) in Young, Adult Women in North America.

Inclusion Criteria:

- A subject whom the investigator believes that she can and will comply with the
requirements of the protocol

- Must have received three doses of study vaccine or placebo control in study
580299/001.

- Must have completed study 580299/007.

- Written informed consent must be obtained from the subject prior to enrollment in the
study.

- Healthy subjects, as established by medical history and history-directed clinical
examination before entering into the study.

- Subject must have a negative urine pregnancy test.

- Subject must be at least three months post-termination of a pregnancy.

- Subject must be of non-childbearing potential,or subjects are required to be
abstinent or use adequate contraceptive precautions for 30 days prior to vaccination.
Subjects are also required to agree to continue such precautions for two months after
completion of the vaccination series.

Exclusion Criteria:

- Pregnant or breastfeeding.

- A woman planning to become pregnant or planning to discontinue contraceptive
precautions during the study until approximately 2 months after the last vaccination.

- Use of any investigational or non-registered product other than the study vaccine
within 30 days preceding the first dose of study vaccine, or planned use during the
study period.

- Chronic administration of immunosuppressants or other immune-modifying drugs within
six months prior to the first vaccine dose or planned administration during the study
period.

- Planned administration/administration of a vaccine not foreseen by the study protocol
within 30 days of each dose of vaccine. Administration of some routine vaccines up to
8 days before each dose of study vaccine is allowed.

- Previous vaccination against HPV, or planned administration of any HPV vaccine other
than that foreseen by the study protocol during the study period.

- previous administration of components of the investigational vaccine outside of
protocol 580299/001.

- Any medically diagnosed or suspected immunosuppressive or immunodeficient condition,
based on medical history and physical examination

- History of allergic disease, suspected allergy or reactions likely to be exacerbated
by any component of the study vaccines,

- Hypersensitivity to latex

- Acute or chronic, clinically significant pulmonary, cardiovascular, neurologic,
hepatic or renal functional abnormality, as determined by physical examination or
laboratory screening tests.

- Cancer or autoimmune disease under treatment.

- Administration of immunoglobulins and/or any blood products within the three months
(90 days) preceding enrollment or planned administration during the study period.

- Acute disease at the time of enrollment. All vaccines can be administered to persons
with a minor illness

- Heavy bleeding or heavy vaginal discharge in which a pelvic exam cannot be performed.