Immunogenicity and Safety of Meningococcal Vaccine GSK134612 Given as 1 or 2 Doses to Healthy 9-12 Months Old Toddlers.

The protocol posting has been amended to reflect changes as a consequence of an amendment to
the protocol and also to comply with the FDA amendment Act, Sep 2007. Sections impacted are
Brief Title, Official Title of the study, Brief Summary, Key Inclusion & Exclusion criteria.

Inclusion Criteria:

- Subjects whose parents/guardians the investigator believes can and will comply with
the requirements of the protocol

- A male or female of 9 months of age (has not attained 10 months of age) at the time of
enrollment.

- Up to date on vaccinations based on ACIP recommendations and the standard practice at
the investigational site.

- Written informed consent obtained from parents/guardian of the subject.

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

Exclusion Criteria:

- Use of any investigational or non-registered product (drug or vaccine) other than the
study vaccine(s) within 30 days preceding enrollment, or planned use during the study
period.

- Chronic administration (defined as more than 14 days) of immunosuppressants or other
immune-modifying drugs within six months prior to the vaccine dose.

- Planned administration/ administration of a vaccine not foreseen by the study protocol
within 1 month of a dose of study vaccine(s), with the exception of influenza vaccine.

- Planned administration of a tetanus toxoid (TT) containing vaccine throughout the
active phase of the study (through one month after the last vaccination).

- Previous vaccination with meningococcal polysaccharide or conjugate vaccine of
serogroup A, C W and/or Y.

- History of meningococcal diseases.

- Any confirmed or suspected immunosuppressive or immunodeficient condition (congenital
or secondary), including human immunodeficiency virus (HIV) infection, based on
medical history and physical examination (no laboratory testing is required).

- A family history of congenital or hereditary immunodeficiency, until the immune
competence of the potential vaccine recipient is demonstrated.

- History of reactions or allergic disease likely to be exacerbated by any component of
the vaccine.

- Major congenital defects or serious chronic illness.

- History of any neurologic disorders or seizures.

- Acute disease at the time of enrollment.

- Administration of immunoglobulins and/or any blood products within the three months
preceding the first dose of study vaccine or planned administration during the active
phase of the study (through one month after the last dose of study vaccine).