Study in Adolescents/Adults to Evaluate the Persistence up to 3.5 Yrs of GSK Biologicals Meningococcal Vaccine 134612

Assess Long Term Persistence of a Primary Dose of GSK Biologicals' Meningococcal Vaccine 134612 Versus One Dose of Mencevax™ ACWY in Healthy Adolescents/Young Adults (15 to 19 Years at Vaccination)

This study will investigate the long-term protection offered by GSK Biologicals' meningococcal vaccine 134612 up to 3.5 years after vaccination. Subjects were vaccinated at 15 to 19 years of age. This extension phase starts 18 months after vaccination and part of the subjects who were vaccinated in the primary study will be enrolled in this extension phase. No new subjects will be enrolled. This protocol posting deals with objectives & outcome measures of the extension phase 18, 30 and 42 months after vaccination. The objectives & outcome measures of the primary phase are presented in a separate protocol posting (NCT00126945). The Protocol Posting has been updated in order to comply with the FDA Amendment Act, September 2007.

Subjects were previously vaccinated at 15 to 19 years of age with GSK Biologicals' meningococcal vaccine 134612 or with Mencevax™ ACWY. This extension phase starts 18 months after vaccination and part of the subjects will be enrolled in this extension phase. No additional vaccines will be administered during this study and no new subjects will be enrolled. The subjects will have three blood samples taken: at 18, 30 and 42 months after vaccination.

Inclusion Criteria:

• Subjects who the investigator believes that they and/or their parents/guardians can and will comply with the requirements of the protocol.
• A male or female, who was primed with meningococcal vaccine 134612 or Mencevax™ ACWY in the primary vaccination study 18 months before the first persistence assessment and who completed that study.
• Written informed consent obtained from the subject/ from the parent or guardians of the subject.
• Written informed assent obtained from the subject, as applicable, at the time of study entry.

Exclusion Criteria:

• Administration of a meningococcal polysaccharide or a meningococcal polysaccharide conjugate vaccine since the last visit of the primary vaccination study.