title: Safety and immunogenicity of a booster dose of a 3-antigen Staphylococcus aureus vaccine (SA3Ag) in healthy adults: A randomized phase 1 study.
abstract: A 2-stage, phase 1, randomized, placebo-controlled study in healthy adults to assess immunogenicity and safety of a booster dose at three dose levels of a 3-antigen Staphylococcus aureus vaccine (SA3Ag) containing recombinant clumping factor A (ClfA) and capsular polysaccharides 5 and 8 (CP5 and CP8) conjugated to a diphtheria toxoid.
  
  
  
  Six months after initial single vaccination, in Stage 2, SA3Ag recipients were randomized (1:1) to booster vaccination or placebo, while Stage 1 placebo recipients received placebo again. Pre- and post-vaccination blood samples were analyzed.
  
  
  
  In Stage 2 (n = 345), pre-booster CP5 and CP8 titers remained high with no increase post-booster. ClfA titers remained high after initial vaccination and increased post-booster, approaching the peak response to the initial dose. Post-booster local reactions were more frequent and of greater severity than reported after the initial vaccination, particularly for the high-dose level recipients. Post hoc analysis showed no dose-response pattern and no obvious association between diphtheria toxoid titers and local reactions after initial or booster vaccination.
  
  
  
  Immune responses after the initial vaccination persisted for the 12 months studied, with little additional response after the booster dose at 6 months. Post-booster injection site reactions were more frequent and more severe but self-limiting. CLINICALTRIALS.
  
  
  
  NCT01018641.
authors: Vaccinology and Immunology Research Trials Unit, Women's and Children's Hospital and Robinson Research Institute and School of Medicine, University of Adelaide, Adelaide, SA, Australia. Electronic address: helen.marshall@adelaide.edu.au.
authors: Helen
authors: H
authors: Marshall
authors: Queensland Paediatric Infectious Diseases, Clinical Trials Centre, Royal Children's Hospital and Children's Health Service District, Brisbane, QLD, Australia.
authors: Michael
authors: M
authors: Nissen
authors: University of Western Australia, School of Paediatrics and Child Health, Telethon Kids Institute, Perth, WA, Australia.
authors: Peter
authors: P
authors: Richmond
authors: CMAX, Adelaide, SA, Australia.
authors: Sepehr
authors: S
authors: Shakib
authors: Pfizer Inc., Collegeville, PA, USA.
authors: Qin
authors: Q
authors: Jiang
authors: Pfizer Inc., Pearl River, NY, USA.
authors: David
authors: D
authors: Cooper
authors: Pfizer Inc., Collegeville, PA, USA.
authors: Denise
authors: D
authors: Rill
authors: Pfizer Australia Pty Ltd, Sydney, NSW, Australia.
authors: James
authors: J
authors: Baber
authors: Pfizer Inc., Pearl River, NY, USA.
authors: Joseph
authors: J
authors: Eiden
authors: Pfizer Inc., Pearl River, NY, USA.
authors: William C
authors: WC
authors: Gruber
authors: Pfizer Inc., Pearl River, NY, USA.
authors: Kathrin U
authors: KU
authors: Jansen
authors: Pfizer Inc., Pearl River, NY, USA.
authors: Annaliesa S
authors: AS
authors: Anderson
authors: Pfizer Inc., Collegeville, PA, USA.
authors: Edward T
authors: ET
authors: Zito
authors: Pfizer Inc., Pearl River, NY, USA.
authors: Douglas
authors: D
authors: Girgenti
mesh_terms: D000293:Adolescent; D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D000956:Antigens, Viral; D016667:Bacterial Capsules / Q000276:immunology*; D001428:Bacterial Vaccines / Q000494:pharmacology*; D003030:Coagulase / Q000276:immunology; D004167:Diphtheria Toxin / Q000276:immunology; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D007117:Immunization, Secondary; D008297:Male; D008875:Middle Aged; D010919:Placebos; D013203:Staphylococcal Infections / Q000276:immunology* / Q000517:prevention & control*; D013211:Staphylococcus aureus / Q000276:immunology*; D014611:Vaccination / Q000379:methods; D055815:Young Adult
chemical_list: D000956:Antigens, Viral; D001428:Bacterial Vaccines; C515944:ClfA protein, Staphylococcus aureus; D003030:Coagulase; D004167:Diphtheria Toxin; D010919:Placebos; C054106:capsular polysaccharide, type 5, Staphylococcus aureus; C064836:capsular polysaccharide, type 8, Staphylococcus aureus
keywords: Capsular polysaccharide conjugates; Clumping factor A; Functional antibodies; Staphylococcus aureus; Vaccine