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NCT05947643 · ClinicalTrials.gov registry record · Phase 2

Smell in COVID-19 and Efficacy of Nasal Theophylline (SCENT 3)

A Phase 2 study of COVID-19, sponsored by Washington University School of Medicine.

Completed
Registry status
Phase 2
Development phase
77
Enrollment target
1
Study location

NCT05947643: Completed Phase 2 study of COVID-19, sponsored by Washington University School of Medicine.

NCT05947643 is a Phase 2 study of COVID-19 that has completed, run by Washington University School of Medicine. The registered enrollment target is 77 participants, below the 38,465-participant average among 298 other COVID-19 trials with a reported enrollment target (100% lower). The trial reports 1 study location across 1 state. According to ClinicalTrials.gov, the official US trial registry.

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The verdict

NCT05947643, a Phase 2 study of COVID-19, has completed, sponsored by Washington University School of Medicine.

COMPLETED
Registry status
Phase 2
Development phase
77 participants
Enrollment target
1
Study location

Study Summary

The purpose of this Phase II trial is to test the effectiveness of intranasal theophylline irrigations for the treatment of COVID-19 related smell dysfunction. The investigators will compare the effect of theophylline nasal rinses versus placebo nasal rinses on smell symptoms. Participants will be asked to rinse their nose with a medication or placebo capsule dissolved in saltwater twice daily for 12 weeks and fill out surveys about smell before, during, and at the end of treatment. This study will also be used to describe adverse effects related to intranasal theophylline irrigation.

Primary Outcome

The Clinical Global Impression-Improvement scale (CGI-I) is a subjective rating scale used to measure changes in a patient's condition over time. It ranges from 1 to 7, where 1 means "Very Much Improved," 2 means "Much Improved," 3 means "Minimally Improved," 4 means "No Change," 5 means "Minimally Worse," 6 means "Much Worse," and 7 means "Very Much Worsened." In this study, participants reporting scores of 1, 2, or 3 on the CGI-I are considered responders to treatment. The primary analysis wil

Conditions Studied

Interventions

  • DRUG Placebo
  • DRUG theophylline

Study Locations (1)

Missouri

  • Washington University School of Medicine - St Louis

Trial Details

FieldValue
Enrollment Target 77 participants
Start Date 2022-11-22
Est. Completion 2025-08-04
Phase Phase 2

What the finished NCT05947643 record still lists

NCT05947643 is an interventional study that assigns participants to a tested intervention. The registry caps enrollment at 77 participants, a relatively small participant target, below the 38,465-participant average among 298 other COVID-19 trials with a reported enrollment target (100% lower).

The record links to 1 condition, with COVID-19 appearing as the primary indexed condition, and to 2 interventions - of which Placebo is the first listed.

NCT05947643 reports a single indexed study location in Missouri.

Frequently Asked Questions

What is clinical trial NCT05947643 about?

NCT05947643 is a clinical study titled "Smell in COVID-19 and Efficacy of Nasal Theophylline (SCENT 3)". The purpose of this Phase II trial is to test the effectiveness of intranasal theophylline irrigations for the treatment of COVID-19 related smell dysfunction. The investigators will compare the effect of theophylline nasal rinses versus placebo nasal rinses on smell symptoms. Participants will be a...

What is the current status of trial NCT05947643?

This trial is currently completed. It is a Phase 2 study. The enrollment target is 77 participants. The study started on 2022-11-22. Estimated completion is 2025-08-04.

What conditions does trial NCT05947643 study?

This clinical trial studies the following conditions: COVID-19.

What interventions are being tested in trial NCT05947643?

The interventions under investigation include: Placebo (DRUG), theophylline (DRUG).

Who is sponsoring clinical trial NCT05947643?

This trial is sponsored by Washington University School of Medicine, which has 1,502 total clinical trials registered on ClinicalTrials.gov.

Where is trial NCT05947643 being conducted?

This trial has 1 study location across Missouri. Contact the study sites directly through ClinicalTrials.gov for enrollment availability.

Similar trials for COVID-19

Matched on the same primary condition, ranked to surface studies in the same phase first, then by recruiting status, no relevance scoring or editorial curation.

Where NCT05947643's enrollment target sits among peer trials

77 224th of 298 higher than 75 of 298 other COVID-19 trials

participants (enrollment target), bucketed by value

Each bar is a band; taller bars hold more other COVID-19 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 NCT05947643, the US trial registry maintained by the National Library of Medicine. NCT05947643 (small enrollment · single site footprint · completed) retrieved and formatted by PlainTrial, see methodology.