Sodium Citrate for Loss of Smell After COVID-19

Overseen By Lauren Cook

Age: 18+

Sex: Any

Trial Phase: Phase 2

Sponsor: University of North Carolina, Chapel Hill

Disqualifiers: Smoking, Chronic sinusitis, Head trauma, others

Stay on Your Current Meds You can continue your current medications while participating

Prior Safety Data This treatment has passed at least one previous human trial

Compensation: Varies

Number of Visits: 5

Duration: 12 weeks

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial tests whether a nasal spray with sodium citrate can improve the sense of smell in individuals who lost it after COVID-19. It compares the effects of sodium citrate spray with a normal saline spray (0.9% sodium chloride solution), alongside smell retraining exercises. Participants will use the spray and perform the exercises twice daily for 12 weeks. The trial seeks individuals who continue to experience difficulty smelling more than three months after a positive COVID-19 test. As a Phase 2 trial, it measures the treatment's effectiveness in an initial, smaller group, offering participants a chance to contribute to important research.

Will I have to stop taking my current medications?

The trial information does not specify whether you need to stop taking your current medications. However, if you are using any investigational drugs or treatments for smell issues, you must stop those for at least three months before joining the trial.

Is there any evidence suggesting that this trial's treatments are likely to be safe?

Research has shown that sodium citrate can improve the sense of smell by influencing how signals reach the brain. It captures calcium, altering how smell signals are processed in the nose. This method may benefit those who lost their sense of smell after COVID-19.

The treatment is currently in a phase 2 trial, indicating some safety in earlier studies. Although detailed safety information for sodium citrate nasal spray specifically for smell loss is limited, its use in other areas suggests it is generally well-tolerated. So far, no major harmful side effects have been reported. However, as this is an experimental treatment, researchers will closely monitor participants for any negative effects during the trial. ^{1 2 3 4 5}

Why do researchers think this study treatment might be promising for loss of smell after COVID-19?

Unlike standard treatments for loss of smell after COVID-19, which often include olfactory training alone or corticosteroid sprays, sodium citrate offers a new approach by potentially altering the nasal environment to enhance smell recovery. Sodium citrate is administered as a nasal spray, which is a straightforward and non-invasive method, providing an alternative to more complex treatments. Researchers are excited about sodium citrate because it may work by modulating calcium ions in the nasal passages, thus directly targeting the underlying mechanisms of smell loss. This novel mechanism could offer a more effective and faster recovery pathway for patients struggling with post-COVID-19 olfactory issues.

What evidence suggests that sodium citrate might be an effective treatment for loss of smell after COVID-19?

Research has shown that sodium citrate nasal spray might help people regain their sense of smell after losing it due to reasons like long-term effects from COVID-19. In this trial, participants in the Sodium Citrate arm will use sodium citrate nasal spray and perform olfactory training twice a day for 12 weeks. One study found that people using sodium citrate experienced better improvements in their sense of smell compared to those who did not use it. This suggests that sodium citrate may help by boosting the smell signals in the nose, making it easier to notice scents. Although more research is needed, these early results offer hope for those who have lost their sense of smell after COVID-19. ^{1 2 4 6 7}

Who Is on the Research Team?

Brent A. Senior, MD, FACS, FARS

Principal Investigator

University of North Carolina, Chapel Hill

Are You a Good Fit for This Trial?

This trial is for individuals who have lost their sense of smell after having COVID-19 and are still experiencing this issue. Participants will use a nasal spray and undergo smell training twice daily for 12 weeks to see if it helps recover their sense of smell.

Inclusion Criteria

Provision of signed and dated informed consent form

Ability to use nasal spray and be willing to adhere to the nasal spray and olfactory training regimen

I have had a loss of smell since testing positive for COVID-19 over 3 months ago.

Exclusion Criteria

I have a history of chronic sinusitis or nasal polyps.

I have long-term smell loss not caused by COVID-19.

I have had surgery on my sinuses or skull base.

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

1 visit (in-person)

Treatment

Participants use a nasal spray (either sodium citrate or normal saline) followed by olfactory retraining twice a day

12 weeks

3 virtual check-ins at days 7, 28, and 56

Follow-up

Participants are monitored for safety and effectiveness after treatment

4 weeks

1 visit (in-person) for Sniffin' Sticks assessment

What Are the Treatments Tested in This Trial?

Interventions

• Normal Saline
• Olfactory Training Kit - "The Olfactory Kit, by AdvancedRx"
• Sodium Citrate

Trial Overview

The study tests whether adding sodium citrate nasal spray to regular olfactory (smell) retraining can improve the sense of smell in people with long-term loss due to COVID-19, compared to using just normal saline spray with the same training.

How Is the Trial Designed?

Group I: Sodium Citrate Experimental Treatment 2 Interventions

The Sodium Citrate arm will use sodium citrate nasal spray and olfactory training twice a day for 12 weeks.

Group II: Normal Saline Placebo Group 2 Interventions

The Normal Saline arm will use normal saline nasal spray and olfactory training twice a day for 12 weeks.

Who Is Running the Clinical Trial?

University of North Carolina, Chapel Hill

Lead Sponsor

Trials

1,588

Recruited

4,364,000+

Published Research Related to This Trial

In a study of 150 COVID-19 patients with olfactory dysfunction, those treated with both saline irrigation and the nasal corticosteroid triamcinolone showed significantly improved olfactory function after 30 days compared to those receiving no treatment or only saline irrigation.

Topical triamcinolone was effective in reducing the duration of olfactory dysfunction, highlighting its potential as a safe and low-cost treatment option for patients experiencing smell loss due to COVID-19.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Comparison of the Healing Effect of Nasal Saline Irrigation with Triamcinolone Acetonide Versus Nasal Saline Irrigation alone in COVID-19 Related Olfactory Dysfunction: A Randomized Controlled Study. Yildiz, E., Koca Yildiz, S., Kuzu, S., et al.[2022]

Olfactory training (OT) is being investigated as a promising treatment for smell disorders in COVID-19 patients, which can significantly affect their quality of life.

This systematic review will assess the effectiveness and safety of OT, providing crucial evidence to support its use in treating smell dysfunction caused by COVID-19.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Smell disorders in COVID-19 patients: role of olfactory training: A protocol for systematic review and meta-analysis. Zhang, Y., Mei, T., Chen, Y., et al.[2023]

In a pilot study involving 27 patients with persistent olfactory dysfunction due to COVID-19, those treated with a combination of oral corticosteroids and olfactory training showed significant improvement in their sense of smell compared to those who only received olfactory training.

The treatment was found to be safe, with only minimal and transient side effects reported by a few participants, indicating that this approach could be a promising option for patients suffering from long-lasting olfactory loss.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Efficacy and safety of oral corticosteroids and olfactory training in the management of COVID-19-related loss of smell. Le Bon, SD., Konopnicki, D., Pisarski, N., et al.[2021]

Citations

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clinicaltrials.gov

clinicaltrials.gov/study/NCT06204432

Sodium Citrate in Smell Retraining for People With Post- ...

The goal of this pilot study is to assess the feasibility and impact of using sodium citrate nasal spray as an adjunct to olfactory retraining in ...

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pmc.ncbi.nlm.nih.gov

pmc.ncbi.nlm.nih.gov/articles/PMC11409182/

Investigating the efficacy of melatonin, topical sodium ...

Sodium citrate, on the other hand, has shown promising results in improving sense of smell in patients with non-conductive causes of smell loss ...

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reaganudall.org

reaganudall.org/clinical-trial/sodium-citrate-smell-retraining-people-post-covid-19-olfactory-dysfunction

Sodium Citrate in Smell Retraining for People With

The goal of this pilot study is to assess the feasibility and impact of using sodiumcitrate nasal spray as an adjunct to olfactory retraining.

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jamanetwork.com

jamanetwork.com/journals/jamanetworkopen/fullarticle/2839325

Olfactory Dysfunction After SARS-CoV-2 Infection in the ...

This cohort study examines the presence, severity, and patterns of olfactory dysfunction in US adults with and without prior SARS-CoV-2 ...

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pmc.ncbi.nlm.nih.gov

pmc.ncbi.nlm.nih.gov/articles/PMC10436231/

Assessment of COVID-19-related olfactory dysfunction and its ...

A randomised controlled trial of sodium citrate spray for non-conductive olfactory disorders. ... loss: results from a prospective, placebo-controlled trial ...

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pmc.ncbi.nlm.nih.gov

pmc.ncbi.nlm.nih.gov/articles/PMC8711304/

COVID-19 related olfactory dysfunction - PMC - PubMed Central

A French study [7] of 114 patients with confirmed COVID-19 infection showed that 47% of the patients developed loss of sense of smell but less than 5% of the ...

7.

pmc.ncbi.nlm.nih.gov

pmc.ncbi.nlm.nih.gov/articles/PMC8984764/

Treatment strategies for postviral olfactory dysfunction

Sodium citrate is postulated to improve olfaction via calcium sequestration and subsequent depression of feedback inhibition in olfactory signal transduction.