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Clostridium Difficile Vaccine Safety, Tolerability, and Immunogenicity Study in Japanese Adults

A Phase 1, Placebo-controlled, Randomized, Observer-blinded Study To Evaluate The Safety, Tolerability, And Immunogenicity Of Two 3-dose Regimens Of Clostridium Difficile Vaccine Administered In Healthy Japanese Adults Aged 65 To 85 Years.

Status
Completed
Phases
Phase 1
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT02725437
Enrollment
100
Registered
2016-04-01
Start date
2016-02-29
Completion date
2017-02-28
Last updated
2018-07-13

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

Conditions

Clostridium Difficile Associated Disease

Brief summary

The first-in-Japanese study B5091010 has been designed to evaluate the safety, tolerability, and immunogenicity of 2 antigen dose levels of C difficile vaccine when administered as one of two 3-dose regimens to healthy Japanese adults aged 65 to 85 years.

Interventions

0.5 mL intramuscular injection

BIOLOGICALPlacebo

0.5 mL intramuscular injection

Sponsors

Pfizer
Lead SponsorINDUSTRY

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
OTHER
Masking
TRIPLE (Subject, Investigator, Outcomes Assessor)

Eligibility

Sex/Gender
ALL
Age
65 Years to 85 Years
Healthy volunteers
Yes

Inclusion criteria

1. Healthy male and female adults 2. Aged 65 to 85 years

Exclusion criteria

1. Proven or suspected prior episode of Clostridium difficile associated diarrhea 2. Unstable chronic medical condition 3. Disease requiring significant change in therapy or hospitalization for worsening disease within 8 weeks before receipt of study vaccine 4. Serious chronic medical disorders 5. Bleeding diathesis or condition associated with prolonged bleeding time that may contraindicate intramuscular injection 6. Any contraindication to vaccination or vaccine components, including previous anaphylactic reaction to any vaccine or vaccine-related components 7. Subjects with congenital or acquired immunodeficiency disorders 8. Subjects with rheumatologic disorders or other illnesses requiring chronic treatment with known immunosuppressant medications 9. Active or treated leukemia or lymphoma or bone marrow disorder 10. Residence in a nursing home or other long-term care facility, or requirement for semiskilled nursing care or assisted living 11. Abnormality in screening hematology and/or blood chemistry laboratory values

Design outcomes

Primary

MeasureTime frame
Proportions of subjects reporting local reactions (pain, erythema, and induration) and their severity, as self-reported on e-diariesUp to 14 days after each vaccination
Proportions of subjects reporting systemic events (fever, vomiting, diarrhea, headache, fatigue, new or worsening muscle pain, and new or worsening joint pain) and their severity, as self-reported on e-diariesUp to 14 days after each vaccination
Proportions of subjects reporting AEs (categorized according to the Medical Dictionary for Regulatory Activities [MedDRA])From the first vaccination up to 28 days after the last vaccination
Proportions of subjects reporting SAEs (categorized according to the Medical Dictionary for Regulatory Activities [MedDRA])From the first vaccination until 6 months after the last vaccination
Proportions of subjects with abnormal hematology and blood chemistry laboratory assessments7 days or 14 days after each vaccination

Secondary

MeasureTime frame
Proportions of subjects in each vaccine group with fold rises in toxin A-specific neutralizing antibody levelsUp to 6 months after dose 3
Toxin A- and toxin B-specific neutralizing antibody levels, expressed as geometric mean concentrationsUp to 6 months after dose 3
Proportions of subjects in each vaccine group with fold rises in both toxin A- and toxin B-specific neutralizing antibody levelsUp to 6 months after dose 3
Proportions of subjects in each vaccine group with fold rises in toxin B-specific neutralizing antibody levelsUp to 6 months after dose 3
Geometric mean fold rises in toxin A- and toxin B-specific neutralizing antibody levelsUp to 6 months after dose 3
Proportions of subjects in each vaccine group with toxin A-specific neutralizing antibody level ≥ the specified threshold for toxin AUp to 6 months after dose 3
Proportions of subjects in each vaccine group with toxin B-specific neutralizing antibody level ≥ the specified threshold for toxin BUp to 6 months after dose 3
Proportions of subjects in each vaccine group with both toxin A- and toxin B-specific neutralizing antibody levels ≥ the specified threshold for toxin A and the specified threshold for toxin B, respectivelyUp to 6 months after dose 3

Countries

Japan

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Mar 3, 2026