unsatisfactory efficacy data from preceding trial

This study is a continued evaluation of the immune response to StaphVAX , a Staphylococcus aureus type 5 and 8 capsular polysaccharide conjugate vaccine, in end-stage renal disease patients, by giving a 3rd and 4th dose to a subset of the participants in the previous efficacy trial. Participants continue to receive the vaccine or placebo in a blinded manner, and are also randomly assigned to 1 of 2 different intervals between the doses. The immunogenicity is measured by the antibodies in the blood, and typical vaccine safety information is also collected.

Inclusion Criteria:

• Participation in prior study Nabi-1371
• Written informed consent
• Negative serum pregnancy test, where appropriate
• Expect to comply with protocol procedures and schedule

Exclusion Criteria:

• Known HIV
• Immunomodulatory drugs
• Malignancy (other than basal cell or squamous cell carcinoma, carcinoma in situ of the cervix, or early stage prostate cancer)
• Active infection in the 2 weeks prior to study injection
• Serious S. aureus infection within the last 2 months prior to injection
• Hypersensitivity to components of StaphVAX