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NCT03170609 · ClinicalTrials.gov registry record · Phase 2
A Phase 1/2, Randomized, Placebo-controlled, Observer-blinded Trial To Evaluate The Safety, Tolerability, And Immunogenicity Of A Multivalent Group B Streptococcus Vaccine In Healthy Adults 18 To 49 Years Of Age
A Phase 2 study, sponsored by Pfizer.
- Completed
- Registry status
- Phase 2
- Development phase
- 365
- Enrollment target
NCT03170609: Completed Phase 2 study, sponsored by Pfizer.
NCT03170609 is a Phase 2 study that has completed, run by Pfizer. The registered enrollment target is 365 participants, above the 133-participant average among 30,622 other Phase 2 trials with a reported enrollment target (174% higher). According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT03170609, a Phase 2 study, has completed, sponsored by Pfizer.
- COMPLETED
- Registry status
- Phase 2
- Development phase
- 365 participants
- Enrollment target
Study Summary
This is the Phase 1/2 first-in-human, randomized, placebo-controlled, observer-blinded study evaluating the investigational multivalent group B streptococcus vaccine. Healthy adults aged 18 to 49 years of age with no history of group B streptococcal vaccination will be randomized to receive either a single intramuscular dose of multivalent group B streptococcus vaccine (various formulations at 3 dose levels) or a placebo (saline control).
Primary Outcome
Hemoglobin:Grade(G)1: 11-13.5g/dL, G2:9.5-12.4g/dL,G3:8-10.4 g/dL, G4:\<8.0 g/dL; leukocyte increase:G1: 10.8-15\*10\^9/Liter\[L\],G2:\>15-20\*10\^9/L, G3:\>20-25\*10\^9/L, G4:\>25\*10\^9/L,leukocyte decrease: G1: 2.5-3.5\*10\^9/L, G2: 1.5-\<2.5\*10\^9/L, G3: 1-\<1.5\*10\^9/L, G4:\<1\*10\^9/L; neutrophil decrease:G1: 1.5-2\*10\^9/L, G2:1-\<1.5\*10\^9/L, G3:0.5-\<1\*10\^9/L,G4:\<0.5\*10\^9/L; platelets:G1: 125-140\*10\^9/L, G2:100-124\*10\^9/L, G3:25-99\*10\^9/L, G4:\<25\*10\^9/L; eosinophils: G1
Interventions
- BIOLOGICAL Placebo
- BIOLOGICAL Multivalent group B streptococcus vaccine
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 365 participants |
| Start Date | 2017-06-05 |
| Est. Completion | 2018-06-25 |
| Phase | Phase 2 |
What the finished NCT03170609 record still lists
NCT03170609 is an interventional study that assigns participants to a tested intervention. The registered 365 participants enrollment target is mid-sized for trials with a published cap, above the 133-participant average among 30,622 other Phase 2 trials with a reported enrollment target (174% higher).
The record links to 0 conditions, and to 2 interventions - of which Placebo is the first listed.
NCT03170609 does not publish any study locations in the registry export this page uses.
Frequently Asked Questions
What is clinical trial NCT03170609 about?
NCT03170609 is a clinical study titled "A Phase 1/2, Randomized, Placebo-controlled, Observer-blinded Trial To Evaluate The Safety, Tolerability, And Immunogenicity Of A Multivalent Group B Streptococcus Vaccine In Healthy Adults 18 To 49 Years Of Age". This is the Phase 1/2 first-in-human, randomized, placebo-controlled, observer-blinded study evaluating the investigational multivalent group B streptococcus vaccine. Healthy adults aged 18 to 49 years of age with no history of group B streptococcal vaccination will be randomized to receive either a...
What is the current status of trial NCT03170609?
This trial is currently completed. It is a Phase 2 study. The enrollment target is 365 participants. The study started on 2017-06-05. Estimated completion is 2018-06-25.
What interventions are being tested in trial NCT03170609?
The interventions under investigation include: Placebo (BIOLOGICAL), Multivalent group B streptococcus vaccine (BIOLOGICAL).
Who is sponsoring clinical trial NCT03170609?
This trial is sponsored by Pfizer, which has 1,845 total clinical trials registered on ClinicalTrials.gov.
Learn More About Clinical Trials
How this trial's enrollment target compares
Where NCT03170609's enrollment target sits among peer trials
365 121st of 2000 higher than 1,880 of 2,000 other Phase 2 trials
participants (enrollment target), bucketed by value
Each bar is a band; taller bars hold more other Phase 2 trials. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.
Source ClinicalTrials.gov registry export · 2026-08-08
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