Immunogenicity and Safety of GSK Biologicals' Combined Measles-mumps-rubella Vaccine in Volunteers, Seven Years of Age and Older

The purpose of this study is to evaluate the immunogenicity and safety of GSK's trivalent MMR (Priorix®), comparing it to Merck"s MMR vaccine (M-M-R®II), which is approved for use in the US.

This study will evaluate the immunogenicity of GSK's trivalent MMR vaccine (referred to as INV_MMR vaccine) in contrast to the US standard of care (M-M-R®II, Merck and Company, referred to as COM_MMR) when both are used as a second dose in subjects 7 years of age and older. In this study, the INV_MMR vaccine may be administered as a second dose to persons with either a history or formal documentation of at least one dose immunization with any MMR vaccine. This study is intended to support licensure of GSK's MMR vaccine in the US.

Eligibility Criteria:
Inclusion Criteria:

* Subjects who the investigator believes that they and/or their parent(s) or Legally Acceptable Representative(s) (LAR) can and will comply with the requirements of the protocol.
* Male or female subjects 7 years of age or older and born after December 31, 1956\*. \*The only exception to this is health care workers born before 1957 without other evidence of immunity to mumps for which one dose of a live mumps virus vaccine is recommended; therefore this population is eligible for enrollment in this study.
* For all children 7-17 years of age:

  * Written documentation of prior receipt of 1 dose of MMR vaccine administered on or after the first birthday.
* For all adults 18 years of age and older:

  * Prior receipt (written or verbal history) of at least one dose of MMR vaccine.
  * Birth in the US.
* Written informed consent obtained from the subject or from the parent(s)/LAR(s) of the subject (assent will be obtained from subjects who are still legally minors in line with local rules and regulations).
* Subjects in stable health as determined by investigator's physical examination and assessment of subjects' medical history.
* Female subjects of non-childbearing potential may be enrolled in the study.

  * Non-childbearing potential is defined as pre-menarche, current tubal ligation, hysterectomy, or ovariectomy or post-menopause.
* Female subjects of childbearing potential may be enrolled in the study, if the subject

  * Has agreed to be abstinent or practiced adequate contraception during the entire period starting 30 days prior to vaccination(s) until 3 months after receipt of the study vaccination and
  * has a negative pregnancy test on the day of vaccination.

Exclusion Criteria:

* Child in care.
* For all children 7-17 years of age:

  * Previous receipt of more than 1 dose of a measles-containing vaccine.
* Use of any investigational or non-registered product other than the study vaccine(s), during the period starting 30 days preceding the day of study vaccination, (i.e. 30 days prior to Day 0) or planned use during the entire study period.
* Receipt of any measles, mumps or rubella-containing vaccine during the period starting 42 days before the day of study vaccination (i.e. 42 days prior to Day 0).
* Chronic administration (defined as 14 or more consecutive days) of immunosuppressants or other immune-modifying drugs during the period starting 180 days before study vaccination or any planned administration of immune-modifying drugs during the entire study. Inhaled and topical steroids are allowed.
* Administration of immunoglobulins and/or any blood products during the period starting 180 days prior to study vaccination through the immunogenicity evaluation at Visit 2 or Visit 3 (for one-dose or two-dose cohort, respectively).
* Planned administration/ administration of any live viral vaccine not foreseen by the study protocol during the period starting 30 days prior to study vaccination and ending at Visit 2. Live intranasal influenza vaccine or any inactivated vaccine required in the age group may be given at any time, including the day of study vaccination.
* 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.
* History of measles, mumps, or rubella disease.
* Known exposure to measles, mumps, or rubella, during the period starting 30 days before study start (i.e. 30 days prior to Day 0).
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