Exercise-Induced Vocal Cord DysfunctionPhase 2EILONCT07420530
Respiratory and Real-time Dynamics in Exercise-Induced Paradoxical Vocal Fold Motion
A Phase 2 study testing Carbon Dioxide and Mechano-acoustic device in people with Exercise-Induced Vocal Cord Dysfunction and Paradoxical Vocal Fold Motion, run by Indiana University at 1 site in United States.
Trial summary
The overall objectives of the proposed research are to: 1. Evaluate the diagnostic validity of a novel mechano-acoustic signatures of task-characteristic activity during symptomatic and asymptomatic breathing in Exercise-Induced Laryngeal Obstruction (EILO) patients with the use of a novel miniature, soft wearable… Read more about this study
- Who is it for?
- Ages 18 to 26 yearsHealthy volunteers can take part
- Conditions the study is for
- Exercise-Induced Vocal Cord Dysfunction, Paradoxical Vocal Fold Motion, Vocal Cord Dysfunction
- What is being tested?
- Carbon Dioxide and Mechano-acoustic device
- Type of treatment
- Medical device
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 130 participants
- Where
- 1 siteUnited States
- Study dates
- 12 Aug 2026to 20 Jan 2032
- Phase
- Phase 2
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 26 years
- All sexes
- Healthy volunteers accepted
- Adult
Who may be able to join
- Physically active >2.5 hours per week
- Age range of 18-26 years
- Classified as low risk, based on the modified PAR-Q questionnaire, body mass index, and non-smoking status
- Negative history of voice disorders, self-report of cognitive difficulties, asthma or other lung disease, cardiac disease, serious orthopedic injuries, current uncontrolled hypertension, illicit drug use, seizure/epilepsy, claustrophobia, use of beta blockers.
- No metallic, mechanical or magnetic implants such as cardiac devices, cochlear, or other non-removable ear implants, any prosthesis, stents, deep brain stimulator, etc.
Who cannot join
- Individuals older than 26 years and younger than 18 years of age.
- Women who are pregnant or could possibly be pregnant.
- BMI > 25 kg/m2
- A 'yes' answer to any of the 14 questions on the PAR-Q pre-participation questionnaire
- Current smoker
- Positive history of voice disorders, self-report of cognitive difficulties, asthma or other lung disease, cardiac disease, serious orthopedic injuries, current uncontrolled hypertension, illicit drug use, seizure/epilepsy, claustrophobia, use of beta blockers.
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- Presence of metallic, mechanical or magnetic implants such as cardiac devices, cochlear, or other non-removable ear implants, any prosthesis, stents, deep brain stimulator, etc.
- Do not report the following: Greater difficulty breathing inside compared to out and difficulty breathing which is exacerbated at peak exercise and stops 1-5 minutes after exercise
- Individuals older than 26 years and younger than 18 years of age.
- Women who are pregnant or could possibly be pregnant.
- BMI > 25 kg/m2
- A 'yes' answer to any of the 14 questions on the PAR-Q pre-participation questionnaire
- Current smoker
- Positive history of voice disorders, self-report of cognitive difficulties, asthma or other lung disease, cardiac disease, serious orthopedic injuries, current uncontrolled hypertension, illicit drug use, seizure/epilepsy, claustrophobia, use of beta blockers.
- Presence of metallic, mechanical or magnetic implants such as cardiac devices, cochlear, or other non-removable ear implants, any prosthesis, stents, deep brain stimulator, etc.
- Significant acute or chronic medical, neurologic, or illness in the patient that, in the judgment of the Principal Investigator, could compromise subject safety, limit the ability to complete the study, and/or compromise the objectives of the study
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
United States1 site, 1 recruiting
- Recruiting
Indiana University
Bloomington, Indiana, 47401
Rita Patel, 812-855-3886, patelrir@iu.edu
About this study
The overall objectives of the proposed research are to:
- Evaluate the diagnostic validity of a novel mechano-acoustic signatures of task-characteristic activity during symptomatic and asymptomatic breathing in Exercise-Induced Laryngeal Obstruction (EILO) patients with the use of a novel miniature, soft wearable skin-mounted device,
- Identify the mechanism/s of paradoxical respiratory control in EILO by quantifying the relationship between pulmonary mechanics, partial pressure of carbon dioxide (PCO2) maintenance, and vocal fold aperture prior to and during symptomatic and asymptomatic exercise ventilation, and
- Identify unique biophysiological factors contributing to EILO among exercisers with and without EILO. Findings will be highly novel and clinically significant for early identification and management of EILO.
Read more
The main study will enroll 60 participants with EILO and 60 without EILO to complete three separate visits:
- Exercise treadmill study
- Free running with the device on the neck
- Undergoing MRI (Magnetic Resonance Imaging) of the vocal tract.
An additional substudy limited to the mechanoacoustic device will enroll 10 additional participants (5 healthy and 5 with EILO). These participants will complete a single study visit during which the mechano-acoustic device will be worn during four sequential conditions.
Read the detailed description
Main Study
At the first study visit, participants will sign informed consent, complete study questionnaires, have their height, weight, and body composition measured, and perform resting pulmonary function tests. Participants will then warm up on the treadmill for 10 minutes. An endoscope will be placed in one nostril until the vocal folds are visible, and subjects will be fitted with a chest strap heart rate monitor, an oro-nasal face mask, and the mechanoacoustic device. This sensor is placed on the neck with a velcro band. Participants will then undergo a graded exercise test during which a carbon-dioxide enriched gas mixture will be administered. The amount of the gas mixture will be titrated based on measures of the participant's breathing and lung function. This visit will be video recorded.
At the second study visit, participants will be asked to again wear the mechanoacoustic device while free running for 10 minutes in a large room or on a track. This visit will be video-recorded.
At the third study visit, participants will be asked to undergo an MRI scan, during which they will perform a variety of breathing exercises including rest breathing, rapid breathing, pursed lip breathing, sniff, and open mouth breathing. Research personnel will instruct participants in the various breathing techniques prior to the scan.
Device Only Substudy
Participants will be evaluated using the mechanoacoustic device only at a single visit. Participants will wear the neck device during four sequential conditions: seated rest indoors (15 minutes); standing outdoors (15 minutes); walking outdoors (15 minutes); running outdoors (15 minutes). This visit will be video-recorded.
- Conditions
- Exercise-Induced Vocal Cord Dysfunction, Paradoxical Vocal Fold Motion, Vocal Cord Dysfunction
- Being tested
- Carbon Dioxide, Mechano-acoustic device
- Medical subject headings
- Vocal Cord Dysfunction
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Carbon DioxideDrug
Breathing Hypercapnic Gas (10% CO2 (carbon dioxide) and 21%O2 (oxygen), balance N210% (nitrogen))
Mechano-acoustic deviceDevice
A custom developed mechanoacoustic sensor will be worn on the neck using a Velcro strap. The device will collect audio recordings of breathing and breath sounds and will collect muscle activity from the neck muscles.
| Study group | Role | What they receive |
|---|---|---|
| Control Participants | Active comparator | Participants without Exercise-induced laryngeal obstruction (EILO). Receives: Drug: Carbon Dioxide; Device: Mechano-acoustic device |
| EILO Participants | Active comparator | Not described Receives: Drug: Carbon Dioxide; Device: Mechano-acoustic device |
What is being measured
The primary outcome is the main question the study is designed to answer.
Device measurements from real time running
Muscle activation of cricothyroid/sternohyoid muscle measured via customized surface electromyography amplifier
Measured: Baseline and Periprocedural
Device measurements from real time running
Normalized amplitude (100% of maximum voluntary contraction) Burst duration (milliseconds) prior to and during Exercise-Induced Laryngeal Obstruction event of laryngeal closure.
Measured: Baseline and Periprocedural
Device measurements from real time running
Exercise-Induced Laryngeal Obstruction signature detected via ultra-low noise micro-electromechanical (MEMS) microphone amplitude (dB) prior to and during EILO. EILO signature detected via accelerometer (g, where g represents the gravitational acceleration of 9.8 m/s2) prior to and during EILO
Measured: Baseline and Perioprocedural
Treadmill testing
Breathing frequency (breaths per minute)
Measured: Baseline and Perioprocedural
Treadmill testing
Tidal volume (Liters)
Measured: Base-line
Treadmill testing
Ventilation (Liters/minute)
Measured: Breath-by-breath baseline and Perioprocedural
Treadmill testing
Partial pressure of arterial carbon dioxide estimated from end-tidal partial pressure of carbon dioxide; PetCO2) (mmHg)
Measured: Baseline and Periprocedural
MRI Upper Airway Size
Length (mm), width (mm), and cross-sectional area (mm2) of oropharynx, supraglottis, glottis, immediate subglottis.
Measured: Baseline
Upper Airway Aerodynamics
pressure (Pa) across oropharynx, supraglottis, and subglottis
Measured: Baseline and Periprocedural
Upper Airway Aerodynamics
volume flow rate (l/s) across oropharynx, supraglottis, and subglottis
Measured: Baseline and Periprocedural
Upper Airway Aerodynamics
flow velocities (m/s) across oropharynx, supraglottis, and subglottis
Measured: Baseline and Periprocedural
Secondary outcomes (1)
Self-rating of dyspnea
Dyspnea self-rating of breathing intensity and breathing unpleasantness rating on Visual Analog Scale of 0 to 100mm
Measured: Baseline
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted19 Feb 2026
- Study start12 Aug 2026
- Primary completion20 Jan 2032 (estimated)
- Study completion20 Jan 2032 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Exercise-Induced Vocal Cord DysfunctionStudies of the same condition, open and under way.
- More trials run by Indiana UniversityThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 2
- Primary purpose
- Other
- Allocation
- Non-randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Enrolment
- 130 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Indiana University
- Sponsor type
- University, hospital or other
- Collaborators
- Purdue University, National Jewish Health, National Institute on Deafness and Other Communication Disorders (NIDCD)
- Responsible party
- Principal investigator, Rita R. Patel, Indiana University
- Investigators
- Rita Patel, Principal investigator, Indiana University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07420530
- Sponsor's protocol ID
- 29009
- Other IDs
- R01DC023381
- Acronym
- EILO
- Status last verified
- Aug 2026
- First submitted
- 13 Jan 2026
- Last updated
- 14 Aug 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- Yes
- FDA-regulated device
- Yes
- Individual data sharing
- Yes: The data will be available indefinitely, as per NIH's Data Management and Sharing Policy to maximize the appropriate sharing of scientific data.
Study at a glance
From the registry record, last updated by the sponsor on 14 Aug 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Respiratory and Real-time Dynamics in Exercise-Induced Paradoxical Vocal Fold Motion
- ClinicalTrials.gov ID
- NCT07420530
- Acronym / sponsor ID
- EILO / 29009
- Conditions
- Exercise-Induced Vocal Cord Dysfunction, Paradoxical Vocal Fold Motion, Vocal Cord Dysfunction
- Phase
- Phase 2
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 130 participants (estimated)
- Lead sponsor
- Indiana UniversityUniversity, hospital or other
- Collaborators
- Purdue University, National Jewish Health, National Institute on Deafness and Other Communication Disorders (NIDCD)
- Study start
- 12 Aug 2026 (actual)
- Primary completion
- 20 Jan 2032 (estimated)
- Study completion
- 20 Jan 2032 (estimated)
- First posted
- 19 Feb 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The overall objectives of the proposed research are to:
- Evaluate the diagnostic validity of a novel mechano-acoustic signatures of task-characteristic activity during symptomatic and asymptomatic breathing in Exercise-Induced Laryngeal Obstruction (EILO) patients with the use of a novel miniature, soft wearable skin-mounted device,
- Identify the mechanism/s of paradoxical respiratory control in EILO by quantifying the relationship between pulmonary mechanics, partial pressure of carbon dioxide (PCO2) maintenance, and vocal fold aperture prior to and during symptomatic and asymptomatic exercise ventilation, and
- Identify unique biophysiological factors contributing to EILO among exercisers with and without EILO. Findings will be highly novel and clinically significant for early identification and management of EILO.
The main study will enroll 60 participants with EILO and 60 without EILO to complete three separate visits:
- Exercise treadmill study
- Free running with the device on the neck
- Undergoing MRI (Magnetic Resonance Imaging) of the vocal tract.
An additional substudy limited to the mechanoacoustic device will enroll 10 additional participants (5 healthy and 5 with EILO). These participants will complete a single study visit during which the mechano-acoustic device will be worn during four sequential conditions.
Detailed description
Main Study
At the first study visit, participants will sign informed consent, complete study questionnaires, have their height, weight, and body composition measured, and perform resting pulmonary function tests. Participants will then warm up on the treadmill for 10 minutes. An endoscope will be placed in one nostril until the vocal folds are visible, and subjects will be fitted with a chest strap heart rate monitor, an oro-nasal face mask, and the mechanoacoustic device. This sensor is placed on the neck with a velcro band. Participants will then undergo a graded exercise test during which a carbon-dioxide enriched gas mixture will be administered. The amount of the gas mixture will be titrated based on measures of the participant's breathing and lung function. This visit will be video recorded.
At the second study visit, participants will be asked to again wear the mechanoacoustic device while free running for 10 minutes in a large room or on a track. This visit will be video-recorded.
At the third study visit, participants will be asked to undergo an MRI scan, during which they will perform a variety of breathing exercises including rest breathing, rapid breathing, pursed lip breathing, sniff, and open mouth breathing. Research personnel will instruct participants in the various breathing techniques prior to the scan.
Device Only Substudy
Participants will be evaluated using the mechanoacoustic device only at a single visit. Participants will wear the neck device during four sequential conditions: seated rest indoors (15 minutes); standing outdoors (15 minutes); walking outdoors (15 minutes); running outdoors (15 minutes). This visit will be video-recorded.
Study design
- Primary purpose
- Other
- Allocation
- Non-randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Control Participants | Active comparator | Drug: Carbon Dioxide, Device: Mechano-acoustic deviceParticipants without Exercise-induced laryngeal obstruction (EILO). |
| EILO Participants | Active comparator | Drug: Carbon Dioxide, Device: Mechano-acoustic device |
Who may qualify
- Ages
- 18 to 26 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult
Key inclusion criteria (5 listed)
- Physically active >2.5 hours per week
- Age range of 18-26 years
- Classified as low risk, based on the modified PAR-Q questionnaire, body mass index, and non-smoking status
- Negative history of voice disorders, self-report of cognitive difficulties, asthma or other lung disease, cardiac disease, serious orthopedic injuries, current uncontrolled hypertension, illicit drug use, seizure/epilepsy, claustrophobia, use of beta blockers.
- No metallic, mechanical or magnetic implants such as cardiac devices, cochlear, or other non-removable ear implants, any prosthesis, stents, deep brain stimulator, etc.
Key exclusion criteria (16 listed)
- Individuals older than 26 years and younger than 18 years of age.
- Women who are pregnant or could possibly be pregnant.
- BMI > 25 kg/m2
- A 'yes' answer to any of the 14 questions on the PAR-Q pre-participation questionnaire
- Current smoker
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Carbon DioxideBreathing Hypercapnic Gas (10% CO2 (carbon dioxide) and 21%O2 (oxygen), balance N210% (nitrogen)) | Drug | Control Participants, EILO Participants |
| Mechano-acoustic deviceA custom developed mechanoacoustic sensor will be worn on the neck using a Velcro strap. The device will collect audio recordings of breathing and breath sounds and will collect muscle activity from the neck muscles. | Device | Control Participants, EILO Participants |
Primary outcome
Device measurements from real time running
Time frame: Baseline and Periprocedural
Muscle activation of cricothyroid/sternohyoid muscle measured via customized surface electromyography amplifier
Device measurements from real time running
Time frame: Baseline and Periprocedural
Normalized amplitude (100% of maximum voluntary contraction) Burst duration (milliseconds) prior to and during Exercise-Induced Laryngeal Obstruction event of laryngeal closure.
Device measurements from real time running
Time frame: Baseline and Perioprocedural
Exercise-Induced Laryngeal Obstruction signature detected via ultra-low noise micro-electromechanical (MEMS) microphone amplitude (dB) prior to and during EILO. EILO signature detected via accelerometer (g, where g represents the gravitational acceleration of 9.8 m/s2) prior to and during EILO
Treadmill testing
Time frame: Baseline and Perioprocedural
Breathing frequency (breaths per minute)
Treadmill testing
Time frame: Base-line
Tidal volume (Liters)
Treadmill testing
Time frame: Breath-by-breath baseline and Perioprocedural
Ventilation (Liters/minute)
Treadmill testing
Time frame: Baseline and Periprocedural
Partial pressure of arterial carbon dioxide estimated from end-tidal partial pressure of carbon dioxide; PetCO2) (mmHg)
MRI Upper Airway Size
Time frame: Baseline
Length (mm), width (mm), and cross-sectional area (mm2) of oropharynx, supraglottis, glottis, immediate subglottis.
Upper Airway Aerodynamics
Time frame: Baseline and Periprocedural
pressure (Pa) across oropharynx, supraglottis, and subglottis
Upper Airway Aerodynamics
Time frame: Baseline and Periprocedural
volume flow rate (l/s) across oropharynx, supraglottis, and subglottis
Upper Airway Aerodynamics
Time frame: Baseline and Periprocedural
flow velocities (m/s) across oropharynx, supraglottis, and subglottis
1 secondary outcome
Self-rating of dyspnea
Time frame: Baseline
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 14 Aug 2026.
- Individual participant dataSharing planned: Yes. The data will be available indefinitely, as per NIH's Data Management and Sharing Policy to maximize the appropriate sharing of scientific data.
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Rita Patel principal investigator
Indiana University
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 2 study testing Carbon Dioxide and Mechano-acoustic device in people with Exercise-Induced Vocal Cord Dysfunction and Paradoxical Vocal Fold Motion, run by Indiana University at 1 site in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 5 inclusion and 16 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 14 Aug 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 2 studies give the treatment to a larger group to see whether it has the intended effect and to keep checking safety.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Rita R Patel (812-855-3886, patelrir@iu.edu), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Device measurements from real time running (time frame: Baseline and Periprocedural). The study lists 11 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 14 Aug 2026.