Infection with human papillomavirus (HPV) has been clearly established as the central cause of cervical cancer. The current phase 3b study is designed to assess the immunogenicity and safety of GlaxoSmithKline Biologicals' HPV vaccine GSK580299 administered according to an alternative dosing schedule as compared to the standard dosing schedule in young female subjects aged 15 - 25 years. The Protocol Posting has been updated in order to comply with the FDA Amendment Act, Sep 2007.

Inclusion Criteria:

• Subjects who the investigator believes that they and/or their parent(s)/Legally acceptable representative(s) (LAR) can and will comply with the requirements of the protocol
• A female between and including 15 and 25 years of age at the time of the first vaccination.
• Written informed consent obtained from the subject prior to enrolment. For subjects below the legal age of consent, written informed consent must be obtained from the subject's parents/legally acceptable representative (LAR), and written informed assent must be obtained from the subject.
• Healthy subjects as established by medical history and/or clinical examination before entering into the study.
• Subject must be of non-childbearing potential, or if she is of child bearing potential, she must practice adequate contraception for 30 days prior to vaccination, have a negative urine pregnancy test and continue such precautions for 2 months after completion of the vaccination series.
• Subject who had no more than 6 lifetime sexual partners prior to enrolment.

Exclusion Criteria:

• Use of any investigational or non-registered product (drug or vaccine) 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.
• Planned administration/administration of a vaccine not foreseen by the study protocol within 30 days before and 30 days after the first dose of vaccine. Planned administration/administration of routine vaccines up to 8 days before the first dose of study vaccine is allowed. Enrolment will be deferred until the patient is outside of specified window.
• Concurrently participating in another clinical study, at any time during the study period, in which the subject has been or will be exposed to an investigational or a non-investigational product (pharmaceutical product or device).
• 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
• Cancer or autoimmune disease under treatment.
• Any confirmed or suspected immunosuppressive or immunodeficient condition, based on medical history and physical examination.
• History of allergic disease or reactions likely to be exacerbated by any component of the vaccine.
• Hypersensitivity to latex
• Acute disease at the time of enrolment.
• Administration of immunoglobulins and/or any blood products within the three months preceding blood sampling.
• Pregnant or breastfeeding female.
• Female planning to become pregnant, likely to become pregnant (as determined by the investigator) or planning to discontinue contraceptive precautions during the study period starting at visit one and up to two months after the last vaccine dose.
• Acute or chronic clinically significant pulmonary, cardiovascular, hepatic or renal function abnormality as determined by physical examination or lab tests.

Patient-level data for this study will be made available through www.clinicalstudydatarequest.com following the timelines and process described on this site.