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NCT05085366 · ClinicalTrials.gov registry record · Phase 3

A Study to Evaluate the Efficacy, Safety, and Immunogenicity of mRNA-1647 Cytomegalovirus (CMV) Vaccine in Healthy Participants 16 to 40 Years of Age

A Phase 3 study, sponsored by ModernaTX.

Terminated
Registry status
Phase 3
Development phase
7,454
Enrollment target

NCT05085366: Clinical Trial Phase 3 study, sponsored by ModernaTX.

NCT05085366 is a Phase 3 study that was terminated before completion, run by ModernaTX. The registered enrollment target is 7,454 participants, above the 772-participant average among 15,282 other Phase 3 trials with a reported enrollment target (866% higher). According to ClinicalTrials.gov, the official US trial registry.

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The verdict

NCT05085366, a Phase 3 study, was terminated before completion, sponsored by ModernaTX.

TERMINATED
Registry status
Phase 3
Development phase
7,454 participants
Enrollment target

Study Summary

The main purpose of this study is to evaluate the efficacy of mRNA 1647 vaccine in CMV-seronegative female participants and to evaluate the safety and reactogenicity of mRNA-1647 vaccine in all participants. The purpose of the Phase 3 extension substudy is to extend the observation period of the main study and to assess the longer-term immunogenicity, efficacy, and safety of the mRNA-1647 vaccine against primary CMV infection in healthy females who were CMV-seronegative at Baseline of the mRNA-1647-P301 main study (including participants who remain CMV-seronegative upon entry into the extension substudy and participants who seroconverted during the main study). The extension substudy will also evaluate the immune persistence and safety of mRNA-1647 in a subset of female participants who were CMV-seropositive at Baseline of the main study. No interventional vaccine will be administered in the extension substudy.

Interventions

  • BIOLOGICAL Placebo
  • BIOLOGICAL mRNA-1647

Trial Details

FieldValue
Enrollment Target 7,454 participants
Start Date 2021-10-26
Est. Completion 2025-11-04
Phase Phase 3
ModernaTX

90 total trials

Why NCT05085366 stopped before completion

NCT05085366 is an interventional study that assigns participants to a tested intervention. Its 7,454 participants enrollment target places it among the larger protocols in the corpus, above the 772-participant average among 15,282 other Phase 3 trials with a reported enrollment target (866% higher).

The record links to 0 conditions, and to 2 interventions - of which Placebo is the first listed.

NCT05085366 does not publish any study locations in the registry export this page uses.

Frequently Asked Questions

What is clinical trial NCT05085366 about?

NCT05085366 is a clinical study titled "A Study to Evaluate the Efficacy, Safety, and Immunogenicity of mRNA-1647 Cytomegalovirus (CMV) Vaccine in Healthy Participants 16 to 40 Years of Age". The main purpose of this study is to evaluate the efficacy of mRNA 1647 vaccine in CMV-seronegative female participants and to evaluate the safety and reactogenicity of mRNA-1647 vaccine in all participants. The purpose of the Phase 3 extension substudy is to extend the observation period of the mai...

What is the current status of trial NCT05085366?

This trial is currently terminated. It is a Phase 3 study. The enrollment target is 7,454 participants. The study started on 2021-10-26. Estimated completion is 2025-11-04.

What interventions are being tested in trial NCT05085366?

The interventions under investigation include: Placebo (BIOLOGICAL), mRNA-1647 (BIOLOGICAL).

Who is sponsoring clinical trial NCT05085366?

This trial is sponsored by ModernaTX, which has 90 total clinical trials registered on ClinicalTrials.gov.

How this trial's enrollment target compares

Where NCT05085366's enrollment target sits among peer trials

7,454 34th of 2000 higher than 1,967 of 2,000 other Phase 3 trials

participants (enrollment target), bucketed by value

Each bar is a band; taller bars hold more other Phase 3 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 NCT05085366, the US trial registry maintained by the National Library of Medicine. NCT05085366 (large enrollment · none site footprint · terminated) retrieved and formatted by PlainTrial, see methodology.