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

COVID-19 Clinical Trial

Official title:

Smell in COVID-19 and Efficacy of Nasal Theophylline 3

Clinical Trial Details — Status: Recruiting

Administrative data

• NCT number: NCT05947643
• Other study ID #: 202209062
• Status: Recruiting
• Phase: Phase 2
• Start date: November 22, 2022
• Est. completion date: June 2024

Study information

• Verified date: July 2023
• Source: Washington University School of Medicine
• Contact: Jay F Piccirillo, MD
• Phone: 314-362-8641
• Email: piccirj[@]wustl.edu
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial 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.

Description:

COVID-related olfactory dysfunction (OD) is a major symptom of infection with SARS-COV-2, affecting up to 80% of those with COVID-19. While research on the pathogenesis is ongoing, a significant subset is expected to suffer from long-term OD. The investigators seek to test intranasal theophylline nasal irrigation as a potential therapeutic option for treatment of COVID-related OD lasting over 3 months.

Theophylline has been shown to improve outcomes in post-viral OD in pilot studies, and initial data suggests therapeutic benefit in patients with post-COVID OD with minimal systemic absorption.

The primary hypothesis is that theophylline irrigation will be more effective than placebo saline irrigation for COVID-19 related OD symptoms. The use of intranasal theophylline will have minimal adverse effects.

Recruitment information / eligibility

• Status: Recruiting
• Enrollment: 240
• Est. completion date: June 2024
• Est. primary completion date: June 2024
• Accepts healthy volunteers: No
• Gender: All
• Age group: 18 Years to 75 Years

Eligibility

Inclusion Criteria:

• Participants will be recruited based on the following inclusion criteria:

1. males and females ages 18 to 75 years

2. located within or willing to travel to the state of Missouri or Illinois

3. Olfactory dysfunction that has persisted for >3 months following suspected COVID-19 infection

4. Baseline University of Pennsylvania Smell Identification Test (UPSIT) consistent with decreased olfactory function (<= 34 in women, <=33 in men). This test is a clinically validated 40-question forced-choice odor identification test where microencapsulated odorants on a strip are released by scratching.70 This will determine that patients have both subjectively and objectively diagnosed OD prior to undergoing treatment.

5. Ability to read, write, and understand English and have access to email.

Exclusion Criteria:

• Individuals will not be allowed to participate in this study if they meet one or more of the following exclusion criteria:

1. History of olfactory dysfunction prior to COVID-19 infection

2. Any use of concomitant therapies specifically for the treatment of olfactory dysfunction

3. Use of or participation in previous trials of intranasal theophylline.

4. Known existence of nasal polyps, prior sinonasal, or anterior skull-based surgery

5. Dependence on theophylline for comorbid conditions such as asthma and chronic obstructive pulmonary disease (COPD)

6. History of an allergic reaction to theophylline or other methylxanthines

7. History of neurodegenerative disease (ie. Alzheimer's dementia, Parkinson's disease, Lewy body dementia, frontotemporal dementia)

8. Pregnant or breastfeeding mothers.

9. Current use of medications with significant (=40%) interactions with theophylline, which include cimetidine, ciprofloxacin, disulfiram, enoxacin, fluvoxamine, interferon- alpha, lithium, mexiletine, phenytoin, propafenone, propranolol, tacrine, thiabendazole, ticlopidine, and troleandomycin.

Related Conditions & MeSH terms

• COVID-19

Intervention

Drug:
• theophylline
capsules dissolved in intranasal irrigation
• Placebo
identical-appearing lactose capsules dissolved in intranasal irrigation

Locations

Country	Name	City	State
United States	Washington University School of Medicine	Saint Louis	Missouri

Sponsors (1)

Lead Sponsor	Collaborator
Washington University School of Medicine

Country where clinical trial is conducted

United States, 

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* Note: There are 66 references in all — Click here to view all references

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Clinical Global Impression Scale (CGI)	The CGI is a 3-item observer-rated scale that measures illness severity (CGIS), global improvement or change (CGIC). The CGI is rated on a 7-point scale, with the severity of illness scale using a range of responses from 1 (normal) through to 7 (amongst the most severely ill patients). CGI scores range from 1 (very much improved) through to 7 (very much worse).; We will measure the response rate defined as the number of participants self-reporting minimal change or larger in the Clinical Global Impression Scale (CGI) scale, divided by the number of participants in each group.	Week 6 and week 12 of treatment
Secondary	Olfactory Dysfunction Outcomes Rating (ODOR)	ODOR is a disease-specific questionnaire that assesses for physical, functional, and emotional limitations in participants with olfactory dysfunction of any etiology. The instrument contains 28 total items with each scored on a 5-point Likert scale from 0 to 4.	Week 6 and week 12 of treatment
Secondary	Assessment of adherence	Number of irrigations completed over the prior 7 days out of a possible 14.	Week 1-2 of treatment
Secondary	Assessment of blind	Participants will be asked to guess whether they are in the theophylline or placebo arm of the study.	Week 1-2 of treatment
Secondary	Adverse effects	Patients will be asked to report any adverse effects they experience.	Patients may report this information any time during 12 weeks of treatment. They are asked about this at weeks 3, 6, 9, and 12 of treatment.

External Links

•   Anosmia Rehabilitation in Patients Post Coronavirus Disease (COVID 19).
•   Corticosteroid Nasal Spray in COVID-19 Anosmia.
•   COVID-19 Anosmia Study.