Bilateral Vocal Fold Paralysis (BVFP)NCT04028674
Functional Electrical Stimulation of the Bilaterally Paralyzed Human Larynx
A study testing Laryngeal Pacing Device in people with Bilateral Vocal Fold Paralysis (BVFP), run by Vanderbilt University Medical Center at 1 site in United States.
Trial summary
The primary purpose of this project is to evaluate the safety of new treatment termed bilateral laryngeal pacing to improve treatment outcomes in patients with bilateral vocal fold paralysis (BVFP) (Aim 1). Read more about this study
- Who is it for?
- Ages 22 years and older
- Conditions the study is for
- Bilateral Vocal Fold Paralysis (BVFP)
- What is being tested?
- Laryngeal Pacing Device
- Type of treatment
- Medical device
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 8 participants
- Where
- 1 siteUnited States
- Study dates
- 14 Jan 2021to Dec 2028
- Phase
- Interventional
- 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 22 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Provision of signed and dated informed consent form.
- Willingness to comply with all study procedures and availability for the duration of the study.
- Male or female adult patients, 22 years of age or older.
- Diagnosis of one of the following at least ten months prior to study enrollment:
- Complete bilateral vocal fold paralysis, with suspected etiological event occurring at least ten months prior to study enrollment. Diagnosis will be documented via medical records and confirmed during the onsite screening visit by a Vanderbilt board certified laryngologist via endoscopy, electromyography and direct laryngoscopy.
- Incomplete bilateral vocal fold paralysis (severe paresis) which significantly impedes respiration may also be considered for participation under the same conditions and per physician recommendation. Patients must present with an NGA less than 20, representing severe laryngeal obstruction. Diagnosis will be documented via medical records and confirmed during the onsite screening visit by a Vanderbilt board certified laryngologist via endoscopy, electromyography, and direct laryngoscopy.
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- Patients receiving repeated botulinum toxin (botox) injections into the thyroarytenoid muscle to treat BVFP may be eligible for participation per physician recommendation.
- Demonstrated glottal opening bilaterally (abductory response) upon percutaneous needle stimulation of PCA muscles (i.e. mean NGA ≥0.05 per vocal fold tested).
- Patients who have previously undergone a recurrent laryngeal nerve reinnervation procedure may be eligible for participation per physician recommendation. Patients must have undergone the laryngeal nerve reinnervation surgery at least 10 months prior to enrollment in the laryngeal pacing study.
- Patients who have previously undergone a recurrent laryngeal nerve reinnervation procedure may be eligible for participation per physician recommendation. Patients must have undergone the laryngeal nerve reinnervation surgery at least 10 months prior to enrollment in the laryngeal pacing study.
- Patients with or without a tracheostomy
- Demonstrated glottal opening bilaterally (abductory response) upon percutaneous needle stimulation of PCA muscles (i.e. mean NGA ≥0.05 per vocal fold tested).
Who cannot join
- Any active illness that is associated with an auto-immune disorder (such as diabetes).
- History of cardiac dysrhythmias or implanted cardiac pacemaker.
- Cardiac irregularities identified in screening electrocardiogram.
- Any electronic implanted medical device that, in the investigator's opinion, could interact with the laryngeal pacemaker.
- Active cardiac disease manifested by unstable angina, recent myocardial infarction, malignant arrhythmias, uncontrolled hypertension (diastolic greater than 110), or decompensated congestive heart failure.
- Patients with underlying comorbidities that, in the investigator's opinion, could potentially warrant a need for oxygen therapy, including but not limited to: Chronic obstructive pulmonary disease, asthma, emphysema, recurrent bronchitis, pneumonia or interstitial lung disease.
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- Bilateral laryngeal immobility from stenosis or arthritis.
- Poor surgical risk patients as determined by the treating surgeon or Vanderbilt Preoperative Evaluation Center (VPEC).
- The abundance of interstitial fat may impede the surgical dissection. In the opinion of the principal investigator or treating physician(s), patients with factors that may complicate the surgical intervention will be excluded.
- Known allergy to barium dye or anesthetics.
- Known allergy to any of the device materials.
- History of aspiration pneumonia, secondary to bilateral vocal fold paralysis
- Persistent thin liquid dysphagia despite standard of care dysphagia management strategies (e.g. small sips, chin tuck, etc.)
- Presence of significant tracheal narrowing.
- Any anatomical abnormality that would jeopardize safe implantation, per the surgeon.
- Any medical condition, that in the opinion of the principal investigator or treating physician would jeopardize the outcome or welfare of the participant.
- Any previous medical treatment that in the opinion of the principal investigator or treating physician would confound the effects of laryngeal pacing.
- Females who are pregnant or plan a pregnancy within 2 years. A pregnancy test will be done as part of the routine pre-operative assessment for all females of child-bearing potential.
Trial locations and contacts
1 site in 1 country.
United States1 site
Vanderbilt University Medical Center
Nashville, Tennessee, 37232
About this study
The primary purpose of this project is to evaluate the safety of new treatment termed bilateral laryngeal pacing to improve treatment outcomes in patients with bilateral vocal fold paralysis (BVFP) (Aim 1). Outcome measures related to voice and ventilation will also provide initial insights into the efficacy of bilateral (Aim 2) and unilateral (Aim 3) stimulation of the implanted device to improve treatment outcomes in patients with BVFP.
Read the detailed description
Despite recent advances in medicine, rehabilitation of the paralyzed larynx remains a complex clinical problem. Based on national health statistics, it is anticipated approximately 7,000 patients will be diagnosed with BVFP in the United States each year. BVFP is a serious and often life-threatening clinical condition. The recurrent laryngeal nerve (RLN) carries motor fibers that innervate both the abductor muscle (posterior cricoarytenoid muscle) and adductor muscles of the vocal folds. Damage to the nerve compromises both of these functions and arrests the vocal folds in a near-closed position. With BVFP, voice tends to be functional, but airway compromise is often severe enough to warrant tracheotomy to relieve inspiratory stridor and dyspnea. If spontaneous recovery does not occur within one year, it is likely that the patient's vocal folds will be chronically paralyzed. In such instances, long-term tracheostomy can be considered. Unfortunately, permanent tracheostomy is associated with complications such as tracheal stenosis, chronic infection, and psycho-social impairment. For this reason, laryngeal surgery is usually recommended to enlarge the airway and restore breathing through the mouth. Procedures such as arytenoidectomy, cordotomy, or repeated Botox injections, regarded as the standard of care for enlarging the airway, also have inherent complications. Specifically, they impair voice and compromise airway protection during swallowing. The limitations associated with these current treatments have prompted investigation into a more physiologic, dynamic approach to rehabilitation: reanimation of the paralyzed PCA muscle by functional electrical stimulation (FES). Ideally, stimulation should be applied during the inspiratory phase of respiration to abduct the vocal folds. This has been termed "laryngeal pacing". During non-inspiratory phases, stimulation would cease, and the vocal folds would passively relax to the midline to allow for normal voice production and airway protection. Previously, our clinical trial of unilateral pacing demonstrated a significantly greater return of ventilation without any compromise of voice or swallowing. However, the level of ventilation was only marginally better than that associated with cordotomy.
In the current project, we will investigate the safety of a novel intervention (laryngeal pacing) for BVFP (Aim 1). The overarching hypothesis is that neuromuscular activation of the PCA muscles bilaterally reestablishes bilateral glottal opening and ventilation through the mouth without alteration of voice or swallowing, compared to a sham-operated control (Aim 2). The ventilation from bilateral pacing should be significantly greater than from unilateral pacing and allow the patient to engage in a normal pre-paralysis activity level (Aim 3).
- Conditions
- Bilateral Vocal Fold Paralysis (BVFP)
- Being tested
- Laryngeal Pacing Device
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Laryngeal Pacing DeviceDevice
Device is an implantable neurostimulation system designed to deliver low-intensity electrical impulses to nerve structures.
| Study group | Role | What they receive |
|---|---|---|
| Early Activation of Laryngeal Pacing device | Experimental | Early Activation of the laryngeal pacing device (n=4) at one-month post-implantation. Receives: Device: Laryngeal Pacing Device |
| Delayed Activation of Laryngeal Pacing device | Sham comparator | Delayed activation of the laryngeal pacing device (n=4) at two months post-implantation. Receives: Device: Laryngeal Pacing Device |
What is being measured
The primary outcome is the main question the study is designed to answer.
Improved ventilation due to laryngeal pacing device as assessed by increase in standard assessment testing (peak inspiratory flow or PIF).
Measured: 12 months
Better voice quality as assessed by decrease in standard assessment testing (Consensus Auditory Perceptual Evaluation of Voice or CAPE-V).
Measured: 12 months
Secondary outcomes (3)
Increased glottal area due to laryngeal pacing device as assessed by increase in normalized glottal area (NGA) results.
Measured: 12 months
Increase in exercise tolerance due to laryngeal pacing device as assessed by treadmill testing.
Measured: 12 months
Better quality of life (QOL) outcomes due to laryngeal pacing device, self assessed via patient reported outcome surveys.
Measured: 12 months
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted23 Jul 2019
- Study start14 Jan 2021
- Primary completionDec 2028 (estimated)
- Study completionDec 2028 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Bilateral Vocal Fold Paralysis (BVFP)Studies of the same condition, open and under way.
- More trials run by Vanderbilt University Medical CenterThe 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 N/A
- Primary purpose
- Device feasibility
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Model description
- Following implantation of the laryngeal pacing device and post-operative visit, participants will be randomized to their treatment group (Early Activation vs. Delayed Activation) and unilateral stimulation side (Right PCA vs. Left PCA) using the REDCap randomization module. 1. To treatment group at a 1:1 ratio-Either the Early Activation Group (n=4) or the Delayed Activation Group (n=4) 2. To unilateral stimulation side at a 1:1 ratio-The side for unilateral stimulation will be either the left PCA muscle (n=4), or the right PCA muscle (n=4)
- Masking
- Single blind
- Who is masked
- Outcomes assessor
- Enrolment
- 8 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Vanderbilt University Medical Center
- Sponsor type
- University, hospital or other
- Collaborators
- National Institute on Deafness and Other Communication Disorders (NIDCD)
- Responsible party
- Principal investigator, David Zealear, PhD, Vanderbilt University Medical Center
- Investigators
- David L. Zealear, PhD, Principal investigator, Vanderbilt University Medical Center
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT04028674
- Sponsor's protocol ID
- 200932
- Other IDs
- 5U01DC016033-05
- Status last verified
- Jul 2026
- First submitted
- 18 Jul 2019
- Last updated
- 29 Jul 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- Yes
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 29 Jul 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Functional Electrical Stimulation of the Bilaterally Paralyzed Human Larynx
- ClinicalTrials.gov ID
- NCT04028674
- Acronym / sponsor ID
- 200932
- Conditions
- Bilateral Vocal Fold Paralysis (BVFP)
- Study type
- Interventional
- Recruitment status
- Active, not recruiting
- Enrolment
- 8 participants (estimated)
- Lead sponsor
- Vanderbilt University Medical CenterUniversity, hospital or other
- Collaborators
- National Institute on Deafness and Other Communication Disorders (NIDCD)
- Study start
- 14 Jan 2021 (actual)
- Primary completion
- Dec 2028 (estimated)
- Study completion
- Dec 2028 (estimated)
- First posted
- 23 Jul 2019 (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 primary purpose of this project is to evaluate the safety of new treatment termed bilateral laryngeal pacing to improve treatment outcomes in patients with bilateral vocal fold paralysis (BVFP) (Aim 1). Outcome measures related to voice and ventilation will also provide initial insights into the efficacy of bilateral (Aim 2) and unilateral (Aim 3) stimulation of the implanted device to improve treatment outcomes in patients with BVFP.
Detailed description
Despite recent advances in medicine, rehabilitation of the paralyzed larynx remains a complex clinical problem. Based on national health statistics, it is anticipated approximately 7,000 patients will be diagnosed with BVFP in the United States each year. BVFP is a serious and often life-threatening clinical condition. The recurrent laryngeal nerve (RLN) carries motor fibers that innervate both the abductor muscle (posterior cricoarytenoid muscle) and adductor muscles of the vocal folds. Damage to the nerve compromises both of these functions and arrests the vocal folds in a near-closed position. With BVFP, voice tends to be functional, but airway compromise is often severe enough to warrant tracheotomy to relieve inspiratory stridor and dyspnea. If spontaneous recovery does not occur within one year, it is likely that the patient's vocal folds will be chronically paralyzed. In such instances, long-term tracheostomy can be considered. Unfortunately, permanent tracheostomy is associated with complications such as tracheal stenosis, chronic infection, and psycho-social impairment. For this reason, laryngeal surgery is usually recommended to enlarge the airway and restore breathing through the mouth. Procedures such as arytenoidectomy, cordotomy, or repeated Botox injections, regarded as the standard of care for enlarging the airway, also have inherent complications. Specifically, they impair voice and compromise airway protection during swallowing. The limitations associated with these current treatments have prompted investigation into a more physiologic, dynamic approach to rehabilitation: reanimation of the paralyzed PCA muscle by functional electrical stimulation (FES). Ideally, stimulation should be applied during the inspiratory phase of respiration to abduct the vocal folds. This has been termed "laryngeal pacing". During non-inspiratory phases, stimulation would cease, and the vocal folds would passively relax to the midline to allow for normal voice production and airway protection. Previously, our clinical trial of unilateral pacing demonstrated a significantly greater return of ventilation without any compromise of voice or swallowing. However, the level of ventilation was only marginally better than that associated with cordotomy.
In the current project, we will investigate the safety of a novel intervention (laryngeal pacing) for BVFP (Aim 1). The overarching hypothesis is that neuromuscular activation of the PCA muscles bilaterally reestablishes bilateral glottal opening and ventilation through the mouth without alteration of voice or swallowing, compared to a sham-operated control (Aim 2). The ventilation from bilateral pacing should be significantly greater than from unilateral pacing and allow the patient to engage in a normal pre-paralysis activity level (Aim 3).
Study design
- Primary purpose
- Device feasibility
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Single blind (outcomes assessor)
- Number of arms
- 2
- Model description
- Following implantation of the laryngeal pacing device and post-operative visit, participants will be randomized to their treatment group (Early Activation vs. Delayed Activation) and unilateral stimulation side (Right PCA vs. Left PCA) using the REDCap randomization module. 1. To treatment group at a 1:1 ratio-Either the Early Activation Group (n=4) or the Delayed Activation Group (n=4) 2. To unilateral stimulation side at a 1:1 ratio-The side for unilateral stimulation will be either the left PCA muscle (n=4), or the right PCA muscle (n=4)
| Arm | Type | Receives |
|---|---|---|
| Early Activation of Laryngeal Pacing device | Experimental | Device: Laryngeal Pacing DeviceEarly Activation of the laryngeal pacing device (n=4) at one-month post-implantation. |
| Delayed Activation of Laryngeal Pacing device | Sham comparator | Device: Laryngeal Pacing DeviceDelayed activation of the laryngeal pacing device (n=4) at two months post-implantation. |
Who may qualify
- Ages
- 22 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (12 listed)
- Provision of signed and dated informed consent form.
- Willingness to comply with all study procedures and availability for the duration of the study.
- Male or female adult patients, 22 years of age or older.
- Diagnosis of one of the following at least ten months prior to study enrollment:
- Patients receiving repeated botulinum toxin (botox) injections into the thyroarytenoid muscle to treat BVFP may be eligible for participation per physician recommendation.
Key exclusion criteria (18 listed)
- Any active illness that is associated with an auto-immune disorder (such as diabetes).
- History of cardiac dysrhythmias or implanted cardiac pacemaker.
- Cardiac irregularities identified in screening electrocardiogram.
- Any electronic implanted medical device that, in the investigator's opinion, could interact with the laryngeal pacemaker.
- Active cardiac disease manifested by unstable angina, recent myocardial infarction, malignant arrhythmias, uncontrolled hypertension (diastolic greater than 110), or decompensated congestive heart failure.
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 |
|---|---|---|
| Laryngeal Pacing DeviceDevice is an implantable neurostimulation system designed to deliver low-intensity electrical impulses to nerve structures. | Device | Delayed Activation of Laryngeal Pacing device, Early Activation of Laryngeal Pacing device |
Primary outcome
Improved ventilation due to laryngeal pacing device as assessed by increase in standard assessment testing (peak inspiratory flow or PIF).
Time frame: 12 months
Better voice quality as assessed by decrease in standard assessment testing (Consensus Auditory Perceptual Evaluation of Voice or CAPE-V).
Time frame: 12 months
3 secondary outcomes
Increased glottal area due to laryngeal pacing device as assessed by increase in normalized glottal area (NGA) results.
Time frame: 12 months
Increase in exercise tolerance due to laryngeal pacing device as assessed by treadmill testing.
Time frame: 12 months
Better quality of life (QOL) outcomes due to laryngeal pacing device, self assessed via patient reported outcome surveys.
Time frame: 12 months
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 29 Jul 2026.
- Individual participant dataSharing planned: No
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. This study is not recruiting at the moment.
David L. Zealear, PhD principal investigator
Vanderbilt University Medical Center
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Laryngeal Pacing Device in people with Bilateral Vocal Fold Paralysis (BVFP), run by Vanderbilt University Medical Center 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 12 inclusion and 18 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: under way, not looking for participants, as of the sponsor's last update on 29 Jul 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. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
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?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Improved ventilation due to laryngeal pacing device as assessed by increase in standard assessment testing (peak inspiratory flow or PIF). (time frame: 12 months). The study lists 2 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 29 Jul 2026; AzTrials last refreshed its copy on 7 Nov 2026.