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NCT04975893 · ClinicalTrials.gov registry record · Phase 2

A Long-Term Extension Study to Evaluate the Immunogenicity and Safety of Cytomegalovirus (CMV) mRNA-1647 Vaccine

A Phase 2 study, sponsored by ModernaTX.

Completed
Registry status
Phase 2
Development phase
135
Enrollment target

NCT04975893: Completed Phase 2 study, sponsored by ModernaTX.

NCT04975893 is a Phase 2 study that has completed, run by ModernaTX. The registered enrollment target is 135 participants, roughly in line with the 133-participant average among 30,622 other Phase 2 trials with a reported enrollment target. According to ClinicalTrials.gov, the official US trial registry.

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The verdict

NCT04975893, a Phase 2 study, has completed, sponsored by ModernaTX.

COMPLETED
Registry status
Phase 2
Development phase
135 participants
Enrollment target

Study Summary

The main purpose of the extension phase of this study is to evaluate the longer-term immune persistence of mRNA-1647 vaccine administered to CMV-seronegative and CMV-seropositive adults who completed Study mRNA-1647-P202 (NCT04232280). For participants in the optional booster phase (BP), the main purpose is to evaluate the long-term immunogenicity and safety of the mRNA-1647 vaccine in both participants receiving a booster dose (BD) and those not receiving a BD, and to additionally evaluate the reactogenicity in participants receiving a BD.

Interventions

  • BIOLOGICAL mRNA-1647
  • OTHER mRNA-1647

Trial Details

FieldValue
Enrollment Target 135 participants
Start Date 2021-06-18
Est. Completion 2026-01-19
Phase Phase 2
ModernaTX

90 total trials

What the finished NCT04975893 record still lists

NCT04975893 is an interventional study that assigns participants to a tested intervention. The registered 135 participants enrollment target is mid-sized for trials with a published cap, roughly in line with the 133-participant average among 30,622 other Phase 2 trials with a reported enrollment target.

The record links to 0 conditions, and to 2 interventions - of which mRNA-1647 is the first listed.

NCT04975893 does not publish any study locations in the registry export this page uses.

Frequently Asked Questions

What is clinical trial NCT04975893 about?

NCT04975893 is a clinical study titled "A Long-Term Extension Study to Evaluate the Immunogenicity and Safety of Cytomegalovirus (CMV) mRNA-1647 Vaccine". The main purpose of the extension phase of this study is to evaluate the longer-term immune persistence of mRNA-1647 vaccine administered to CMV-seronegative and CMV-seropositive adults who completed Study mRNA-1647-P202 (NCT04232280). For participants in the optional booster phase (BP), the main pu...

What is the current status of trial NCT04975893?

This trial is currently completed. It is a Phase 2 study. The enrollment target is 135 participants. The study started on 2021-06-18. Estimated completion is 2026-01-19.

What interventions are being tested in trial NCT04975893?

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

Who is sponsoring clinical trial NCT04975893?

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

How this trial's enrollment target compares

Where NCT04975893's enrollment target sits among peer trials

135 532nd of 2000 higher than 1,464 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 NCT04975893, the US trial registry maintained by the National Library of Medicine. NCT04975893 (mid enrollment · none site footprint · completed) retrieved and formatted by PlainTrial, see methodology.