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Evaluation of a Single Vaccination With One of Three Ascending Dose Levels of a 4-Antigen Staphylococcus Aureus Vaccine (SA4Ag) in Healthy Adults Aged 18 to <65 Years

A Phase 1/2 Placebo-controlled, Randomized, Double-blind Trial To Evaluate The Safety, Tolerability, And Immunogenicity Of 3 Ascending Dose Levels Of A 4-antigen Staphylococcus Aureus Vaccine (sa4ag) In Healthy Adults Aged 18 To <65 Years

Status
Completed
Phases
Phase 1
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT01364571
Enrollment
456
Registered
2011-06-02
Start date
2011-08-31
Completion date
2013-01-31
Last updated
2019-03-04

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Staphylococcal Infections

Keywords

Staphylococcus aureus, vaccine, staphylococcal infection

Brief summary

This is a first-in-human (Phase 1) and Phase 2 study of a single vaccination with one of three dose levels of an investigational vaccine against Staphylococcus aureus (SA4Ag). The main goal of the study is to determine how safe and well tolerated the vaccine is as well as to describe the immune response elicited by the vaccine in healthy adults aged 18 to \<65 years. In addition, the study aims to assess the effect of the SA4Ag vaccine on the presence of the Staphylococcus aureus on the skin and within the nose, throat and perineum of healthy adults aged 18 to \<65 years.

Interventions

Subjects receive 1 intramuscular injection (0.5 mL) of the low dose level of the SA4Ag vaccine.

PROCEDUREBlood draw

Blood for hematology, coagulation and blood chemistry will be collected at a minimum of 3 timepoints from Phase 1 subjects. Blood for immunogenicity will be collected from all subjects at various timepoints.

Colonization swabs will be collected from all subjects at various time points throughout the study.

Subjects receive 1 intramuscular injection (0.5 mL) of the mid dose level of the SA4Ag vaccine.

PROCEDUREBlood sample

Blood for hematology, coagulation and blood chemistry will be collected at a minimum of 3 timepoints from Phase 1 subjects. Blood for immunogenicity will be collected from all subjects at various timepoints.

Subjects receive 1 intramuscular injection (0.5 mL) of the high dose level of the SA4Ag vaccine.

BIOLOGICALPlacebo

Subjects receive one intramuscular injection (0.5 mL) of commercially available normal saline.

Sponsors

Pfizer
Lead SponsorINDUSTRY

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
DOUBLE (Subject, Investigator)

Eligibility

Sex/Gender
ALL
Age
18 Years to 64 Years
Healthy volunteers
Yes

Inclusion criteria

* Healthy adults aged 18 to \<65 years at enrollment, as determined by medical history, physical examination, and the clinical judgment of the investigator to be eligible for the study. Subjects with preexisting chronic medical conditions determined to be stable may be included. * Availability for the entire duration of the study, and able to comply with scheduled visits, treatment plan, laboratory tests, and other study procedures including completion of the electronic diary (e-diary) from Day 1 to Day 14 following vaccination(s). * Ability to be contacted by telephone during study participation. * All male and female subjects who are biologically capable of having children must agree and commit to the use of a reliable method of birth control for the duration of the study.

Exclusion criteria

* Unstable chronic medical condition or disease requiring significant change in therapy or hospitalization within 3 months before receipt of study vaccine. * Serious chronic medical disorders and any other disorder that in the investigator's opinion precludes the subject from participating in the study * Donation of blood volume of 250 mL or greater (excluding protocol-required blood collection), or donation of plasma within 3 months prior to enrollment. * Bleeding condition associated with prolonged bleeding time that may contraindicate intramuscular injection or blood draw including subjects taking anticoagulant, antiplatelet and/or antithrombotic agents except for low-dose daily aspirin within 30 days before enrollment through 1 month post-vaccination. * Any contraindication to vaccination or vaccine components. * Immunocompromised persons and subjects currently on immunosuppressive therapy or with a history of immunosuppressive therapy, including chemotherapy agents or long term systemic corticosteroids. * Previous administration of S. aureus vaccination. * Any infection proven or suspected to be caused by S. aureus within 6 months preceding study vaccination. * Receipt of blood products or immunoglobulins (including monoclonal antibodies) within 12 months before enrollment through conclusion of the study. * Participation in other investigational or interventional studies within 30 days before the current study begins and/or during study participation. * Subjects who are investigational site staff members or subjects who are immediate family members (1st degree relatives) of investigational site staff members or Pfizer employees directly involved in the conduct of the trial. * Residence in a nursing home or long-term care facility or requirement for semiskilled nursing care. * For Phase 1 subjects only, any abnormality in screening hematology, coagulation and/or blood chemistry laboratory values. * Women who are pregnant (as determined by urine pregnancy test) or breastfeeding. * Other severe acute or chronic medical or psychiatric condition or laboratory abnormality that may increase the risk associated with study participation or investigational product administration or may interfere with the interpretation of study results and, in the judgment of the investigator, would make the subject inappropriate for entry into this study.

Design outcomes

Primary

MeasureTime frame
Proportion of subjects achieving antibody responses to specific antigens with results greater than or equal to thresholds specific to each of the 4 antigens in the vaccine based on immunoglobulin-binding and/or opsonophagocytic activity assays.1 month
Number and proportion of subjects reporting local reactions (size of redness and/or swelling and severity of pain at the injection site) and severity of the local reactions as self-reported on electronic diaries (e-diaries)14 days
Number and proportion of subjects reporting solicited systemic events (fever, vomiting, diarrhea, headache, fatigue, new or worsening muscle pain, new or worsening joint pain) and severity of solicited systemic events self-reported on electronic diaries14 days
Number and proportion of subjects reporting unsolicited AEs and serious adverse events (SAEs) categorized according to the Medical Dictionary for Regulatory Activities (MedDRA)1 month (AEs), 6 months (SAEs)
Number and proportion of Phase 1 subjects with abnormal hematology, coagulation and blood chemistry lab assessments; number and proportion of Phase 1 subjects with grading shifts in hematology, coagulation and blood chemistry laboratory assessments.14 days

Secondary

MeasureTime frame
Immunoglobulin concentrations for each antigen at each applicable blood sampling time point,various, up to 12 months
Opsonophagocytic activity (OPA) titers at each applicable blood sampling time point,1 month
Immunoglobulin geometric mean fold rise (GMFR) for each antigen1 month
Geometric mean fold rise on opsonophagocytic activity assay titers1 month
Proportion of subjects achieving antibody responses to specific antigens with results greater than or equal to thresholds specific to each of the 4 antigens in the vaccine at at each applicable visitvarious, up to 12 months

Countries

United States

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 28, 2026