Condition category
Ear, Nose and Throat
Date applied
Date assigned
Last edited
Retrospectively registered
Overall trial status
Recruitment status
No longer recruiting
Publication status
Results overdue

Plain English Summary

Background and study aims
Tinnitus (or “ringing in the ears”) describes hearing noises from inside the body. It is often described as hearing ringing, buzzing, humming, grinding, hissing or whistling in the ears. Tinnitus can come and go and can get better over time. However, tinnitus can be more severe causing depression or insomnia (problems falling asleep) and hearing loss. Hearing loss is also associated with the loss of auditory (hearing) hair cells. It is not very clear what can cause sudden tinnitus and it could be related to the changes in the nervous system (the brain) more than it is to just hearing. There is growing evidence that when damage occurs quickly (such as sudden hearing loss) it can impact the brain functioning (working). Therefore, when the loss of auditory hair cells is sudden this can mean that the nervous system does not change the amount of neurons (connections to the brain) that are working in that area. This could be why tinnitus occurs more with sudden hearing loss as opposed to slow hearing loss where the auditory hair cells are less stimulated over time. Using a brain retraining therapy could help reduce the symptoms of tinnitus. Synaptic Adaptation Stability (ARC therapy) is a device that an artificial environment that slowly makes inner auditory hair cells to be less stimulated by decreasing acoustic stimulation (sounds created by the device). This mimics progressive (slow forming) hearing loss. The aim of this study is to examine the influence of hearing loss on tinnitus occurrence and to see how well ARC therapy is at reduce tinnitus symptoms.

Who can participate?
Adults aged 18 to 60 who suffer from permanent tinnitus.

What does the study involve?
Participants are allocated to one of two groups. Participants are given a hearing aid that sits in their ear canal (like a headphone) that they wear daily for eight to ten hours for four months. Those in the first group receive a placebo stimulation (a dummy stimulation). This remains constant throughout the study. Those in the second group begin with the same stimulation as the first group but this decreases in intensity and in signal over time. Participants are assessed for their tinnitus symptoms prior to the study and after the study (four months).

What are the possible benefits and risks of participating?
Participants may benefit from improvement in their emotional stress and improvement in their mood. There are no notable risks with participating however participants could get headaches from wearing the headphones for too long so they are recommended to get rest between wearing the headphones.

Where is the study run from?
Kinetic Center of Advance Audiology LTD (Poland)

When is the study starting and how long is it expected to run for?
June 2016 to December 2016

Who is funding the study?
Bioacoustic LTD (Poland)

Who is the main contact?
Mr Adam Pabiś

Trial website

Contact information



Primary contact

Mr Adam Pabiś


Contact details

Kinetic Centrum Nowoczesnej Audiologii
ul. Paderewski 159
+48 733 149 666

Additional identifiers

EudraCT number

2016-005123-91 number

Protocol/serial number


Study information

Scientific title

ARC synaptic stabilization: Synaptic adaptation therapy as a new treatment for the tinnitus trial



Study hypothesis

1. Tinnitus can be effectively reduced by acoustic treatment strategy that involves long-lasting stimulation that is reduced progressively in frequency and intensity in time
2. Tinnitus is caused by sudden hearing loss that can be manifested from 4 to 20 kHz in frequency were cochlear have less vestibular fibers and this can cause fast acting deprivation of outer hair cell caused by oxidative stress, lipids dysregulation, ischemia by testosterone or estrogen fast decrease
3. If patients have the right diagnosis tinnitus plasticity model and it will have better BDNF neurotrophins level environment therefore tinnitus can be reduced due to reducing stimulation over time (progressive hearing loss environment simulation) that is fit to the tinnitus model

Ethics approval

Nicolaus Copernicus University (Uniwersytet Mikołaja Kopernika w Toruniu) Medical College Bioethics Committee, 29/04/2016, ref: KB 336/2016

Study design

Double blind single centre randomised controlled trial

Primary study design


Secondary study design

Randomised controlled trial

Trial setting

GP practices

Trial type


Patient information sheet

Not available in web format, please use the contact details below to request a patient information sheet




Participants are randomly allocated to either the control group or the intervention group (this is done using a coin toss). Participants are given a synaptic adapter (tone generator) with a stimulation range that covers the range of sudden hearing loss and its intensity confirmed by pre-existing hearing and neurobiological studies. The device is non invasive ear canal headphone. The device is worn daily for eight to ten hours.

Control group: Those in the control group receive the placebo stimulation. They wear the same setting with a consistent tone, duration and frequency (Hz). The stimulation remains constant during the same time.

Intervention group: Participants start at the same tone, duration and frequency (Hz) stimulation as the placebo group but the signal consistently decreases over time (i.e. the interval between sequences increases each week) and the intensity in dB which dropped by three each week (reversal of gradual hearing loss).

The device is worn for four months (109 days). Participants are assessed for their reduction in tinnitus at baseline, and after the intervention period (after four months).

Intervention type



Drug names

Primary outcome measure

Tinnitus reduction is measured by using a tinnitus patient questionnaire at baseline and four months.

Secondary outcome measures

There are no secondary outcome measures.

Overall trial start date


Overall trial end date


Reason abandoned (if study stopped)


Participant inclusion criteria

1. Both women and men
2. Age between 18 and 60 years of age
3. Must be right-handed
4. Must suffer from permanent tinnitus
5. Tinnitus must not last longer than for two years
6. Only two persons with tinnitus lasting for more than two years may participate in the trial
7. Tinnitus may be tone or wide-band one
8. Tinnitus heard in head or ear
9. Movement or sight may modulate tinnitus
11. Have a high level of serotonin tested in the laboratory in serum or blood plasma (>100 µg/l )
12. Small difference in the HDL- LDL cholesterol units of the patient; it should be at the level of 1:1 or very similar (high level of BDNF protein)
14. Hearing loss in the range between 10 kHz and 20 kHz
15. Tinnitus occurs due to the model of increased synapse activity (Tinnitus does not require macroscopic tonotopic map reorganization)
16. Follows the recommendation referring to the diet and physical activity which notified to it before the clinical trial
17. Auditory canals must not be obstructed during the therapy, no inflammation of the middle ear before commencing of the treatment and during its course
18. Average loss of hearing of the patient noted on audiogram does not exceed the level of 70 dB for a single frequency
19. Apart from the gradual loss of hearing the patient had to experience also the sudden loss of hearing visible in the background of dead outer hair cells in the range from 10 to 20 kHz
20. Does not work in the noise
21. Does not suffer from depression, anxieties, sleep disorders

Participant type


Age group




Target number of participants


Participant exclusion criteria

1. Suffers from hearing loss that starts already in the range of from 125 Hz to 10 kHz in one or both ears
2. Suffers from a chronic disease, such as diabetes, kidney failure, cancer
3. Tinnitus is pulsed or not continued
4. Model of nervous system plasticity, increased synchronization, which assumes that the nervous system of the patient underwent the neurons migration process or the reorganization of the auditory cortex, which additionally leads to auditory oversensitivity
5. Auditory Hyperacusis (a negative symptom of hidden hearing loss in the scope of proper hearing or increased synchronization model)
6. The hearing loss exceeds 70 dB of the single frequency
7. In audiogram, the patient manifests a dead zone of the inner ear (destroyed external and internal hair cells)
8. Partially or deaf in one or both ears
9. The auditory canal of the patient obstructed due to cerumen or inflammation of the middle ear
10. Serotonin level of the patient is lower than required.
11. Manifests metabolic disorders, which cannot be adjusted with diet and physical activity (hyperlipidemia), congenital heart disease, in spite of following the diet and physical activities there is a big difference between HDL and LDL cholesterol and high level of triglycerides
12. Works in noise
13. Suffers from depression, anxieties, sleep disorders
14. Does not want to follow the diet and physical activities

Recruitment start date


Recruitment end date



Countries of recruitment


Trial participating centre

Kinetic Center of Advance Audiology LTD
Street Wspólna 1

Sponsor information


Bioacoustic LTD

Sponsor details

Żurawia 43
+48 669 300 003

Sponsor type




Funder type


Funder name

Bioacoustic LTD Poland

Alternative name(s)

Funding Body Type

Funding Body Subtype


Results and Publications

Publication and dissemination plan

Planned publication in a peer reviewed high impact journal.

IPD sharing plan:
The datasets generated during and/or analysed during the current study are/will be available upon request from Dr Artur Bogacz

Intention to publish date


Participant level data

Available on request

Basic results (scientific)

Publication list

Publication citations

Additional files

Editorial Notes