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NCT03183128 · ClinicalTrials.gov registry record · Phase 3

ECOSPOR III - SER-109 Versus Placebo in the Treatment of Adults With Recurrent Clostridium Difficile Infection

A Phase 3 study, sponsored by Seres Therapeutics.

Completed
Registry status
Phase 3
Development phase
182
Enrollment target

NCT03183128: Completed Phase 3 study, sponsored by Seres Therapeutics.

NCT03183128 is a Phase 3 study that has completed, run by Seres Therapeutics. The registered enrollment target is 182 participants, below the 772-participant average among 15,282 other Phase 3 trials with a reported enrollment target (76% lower). According to ClinicalTrials.gov, the official US trial registry.

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The verdict

NCT03183128, a Phase 3 study, has completed, sponsored by Seres Therapeutics.

COMPLETED
Registry status
Phase 3
Development phase
182 participants
Enrollment target

Study Summary

Subjects will receive an oral dose of SER-109 in 4 capsules once daily for 3 consecutive days in Treatment Group I or matching placebo once daily for 3 consecutive days in Treatment Group II. The purpose of this study is to demonstrate the superiority of SER-109 vs placebo to reduce recurrence of CDI as determined by a toxin assay in adults up to 8 weeks after initiation of treatment.

Primary Outcome

Recurrence of CDI up to 8 Weeks after initiation of treatment. Recurrence was determined by stool Clostridioides difficile toxin assay.

Interventions

  • DRUG Placebo
  • BIOLOGICAL SER-109

Trial Details

FieldValue
Enrollment Target 182 participants
Start Date 2017-07-10
Est. Completion 2020-09-29
Phase Phase 3
Seres Therapeutics

7 total trials

What the finished NCT03183128 record still lists

NCT03183128 is an interventional study that assigns participants to a tested intervention. The registered 182 participants enrollment target is mid-sized for trials with a published cap, below the 772-participant average among 15,282 other Phase 3 trials with a reported enrollment target (76% lower).

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

NCT03183128 does not publish any study locations in the registry export this page uses.

Frequently Asked Questions

What is clinical trial NCT03183128 about?

NCT03183128 is a clinical study titled "ECOSPOR III - SER-109 Versus Placebo in the Treatment of Adults With Recurrent Clostridium Difficile Infection". Subjects will receive an oral dose of SER-109 in 4 capsules once daily for 3 consecutive days in Treatment Group I or matching placebo once daily for 3 consecutive days in Treatment Group II. The purpose of this study is to demonstrate the superiority of SER-109 vs placebo to reduce recurrence of CD...

What is the current status of trial NCT03183128?

This trial is currently completed. It is a Phase 3 study. The enrollment target is 182 participants. The study started on 2017-07-10. Estimated completion is 2020-09-29.

What interventions are being tested in trial NCT03183128?

The interventions under investigation include: Placebo (DRUG), SER-109 (BIOLOGICAL).

Who is sponsoring clinical trial NCT03183128?

This trial is sponsored by Seres Therapeutics, which has 7 total clinical trials registered on ClinicalTrials.gov.

How this trial's enrollment target compares

Where NCT03183128's enrollment target sits among peer trials

182 1421st of 2000 higher than 579 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 NCT03183128, the US trial registry maintained by the National Library of Medicine. NCT03183128 (mid enrollment · none site footprint · completed) retrieved and formatted by PlainTrial, see methodology.