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NCT04766086 · ClinicalTrials.gov registry record · Phase 2

Trial to Evaluate the Safety, Tolerability, and Immunogenicity of A Multivalent Group B Streptococcus Vaccine When Administered Concomitantly With Tdap in Healthy Nonpregnant Women

A Phase 2 study, sponsored by Pfizer.

Completed
Registry status
Phase 2
Development phase
306
Enrollment target

NCT04766086: Completed Phase 2 study, sponsored by Pfizer.

NCT04766086 is a Phase 2 study that has completed, run by Pfizer. The registered enrollment target is 306 participants, above the 133-participant average among 30,622 other Phase 2 trials with a reported enrollment target (130% higher). According to ClinicalTrials.gov, the official US trial registry.

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The verdict

NCT04766086, a Phase 2 study, has completed, sponsored by Pfizer.

COMPLETED
Registry status
Phase 2
Development phase
306 participants
Enrollment target

Study Summary

This phase 2B, placebo-controlled, randomized, observer-blinded trial will evaluate the safety, tolerability, and immunogenicity of the investigational multivalent group B streptococcus vaccine administered concomitantly with Tdap in healthy nonpregnant women 18 through 49 years of age.

Primary Outcome

Local reactions (redness, swelling, and pain at the injection site of the left arm) were recorded by participants in e-diary. Erythema/Redness and induration/swelling were measured and recorded in measuring device units (1 measuring device unit=0.5 centimeter \[cm\]). Grading: Grade 1/mild (greater than \[\>\] 2.0 to 5.0 cm), Grade 2/moderate (\>5.0 to 10.0 cm), Grade 3/severe (\>10.0 cm) and Grade 4 (necrosis \[swelling\] or necrosis or exfoliative dermatitis \[redness\]). Pain at injection sit

Interventions

  • BIOLOGICAL Placebo
  • BIOLOGICAL Multivalent Group B streptococcus vaccine
  • BIOLOGICAL Tetanus, diphtheria, and acellular pertussis vaccine

Trial Details

FieldValue
Enrollment Target 306 participants
Start Date 2022-08-12
Est. Completion 2023-04-27
Phase Phase 2
Pfizer

1,845 total trials

What the finished NCT04766086 record still lists

NCT04766086 is an interventional study that assigns participants to a tested intervention. The registered 306 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 (130% higher).

The record links to 0 conditions, and to 3 interventions - of which Placebo is the first listed.

NCT04766086 does not publish any study locations in the registry export this page uses.

Frequently Asked Questions

What is clinical trial NCT04766086 about?

NCT04766086 is a clinical study titled "Trial to Evaluate the Safety, Tolerability, and Immunogenicity of A Multivalent Group B Streptococcus Vaccine When Administered Concomitantly With Tdap in Healthy Nonpregnant Women". This phase 2B, placebo-controlled, randomized, observer-blinded trial will evaluate the safety, tolerability, and immunogenicity of the investigational multivalent group B streptococcus vaccine administered concomitantly with Tdap in healthy nonpregnant women 18 through 49 years of age.

What is the current status of trial NCT04766086?

This trial is currently completed. It is a Phase 2 study. The enrollment target is 306 participants. The study started on 2022-08-12. Estimated completion is 2023-04-27.

What interventions are being tested in trial NCT04766086?

The interventions under investigation include: Placebo (BIOLOGICAL), Multivalent Group B streptococcus vaccine (BIOLOGICAL), Tetanus, diphtheria, and acellular pertussis vaccine (BIOLOGICAL).

Who is sponsoring clinical trial NCT04766086?

This trial is sponsored by Pfizer, which has 1,845 total clinical trials registered on ClinicalTrials.gov.

How this trial's enrollment target compares

Where NCT04766086's enrollment target sits among peer trials

306 165th of 2000 higher than 1,835 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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Source: ClinicalTrials.gov NCT04766086, the US trial registry maintained by the National Library of Medicine. NCT04766086 (mid enrollment · none site footprint · completed) retrieved and formatted by PlainTrial, see methodology.