[October 28, 2020: still not recruiting]
Feel free to use content of this letter as needed.
To whom it may concern,
Please terminate Sound Pharmaceuticals, Inc. clinicaltrials.govNCT02779192. This clinical trial is for a noise-induced hearing loss prevention drug SPI-1005 or ebselen. It is planning to recruit participants with noise-induced hearing loss with anticipated start date unknown. Sound Pharmaceuticals’ clinical trial is using noise damage on human subjects to study the effect of ebselen. The noise trauma temporary threshold shift (TTS) methodology designed by the study sponsor—Sound Pharmaceuticals—is unethical and unscientific.
100 dB for 4 hours = Sound Pharmaceuticals clinical trial CSC sound exposure planned for unprotected participants.
100 dB for 15 minutes = current international and USA National Institute of Occupational Safety & Health (NIOSH) unprotected daily noise exposure limit.
100 dB for 1 hour = out of date Occupational Safety & Health Administration (OSHA) unprotected daily exposure limit.
Unprotected exposure to the planned clinical trial’s high level and duration of noise trauma is scientifically proven to cause hidden hearing loss also known as cochlear synaptopathy. This is noise-induced permanent hearing nerve damage that progresses even after temporary symptoms go away. Symptoms of cochlear synaptopathy include temporary hearing changes, speech distortion or Words in Noise (WIN) deficit, and tinnitus or hyperacusis (decreased sound tolerance).
Sound Pharmaceuticals, Inc., their employees, and associates (including Dr. Colleen Le Prell) have denied the existence of hidden hearing loss or cochlear synaptopathy after occasional noise trauma. This directly contradicts all independent scientific research, including leading international experts in this field who include Kujawa and Liberman.
The proposed clinical trial participants with pre-existing noise-induced hearing loss are even more vulnerable to noise trauma than people with normal hearing. Experts believe additional noise trauma will cause additional cochlear synaptopathy including progressive communication degradation long after temporary symptoms go away.
It is unethical for medical research to cause permanent harm to human subjects as per the Helsinki Declaration and the Nuremburg Code. Causing noise-induced hearing health damage in humans to study a drug is not ethical. Researchers would never be allowed to run clinical trials where they cause vision damage or heart damage to study a drug or treatment.
Please terminate this unethical and unscientific clinical trial.
Sincerely, Jan L. Mayes
For more evidence-based science, google cochlear synaptopathy.
- Chasin, M. (February 2017). Temporary Threshold Shift (TTS) is NOT so Temporary. Expert Roundtable: Music & Hearing | February 2017 Hearing Review. http://www.hearingreview.com/2017/02/temporary-threshold-shift-tts-not-temporary/
- Kujawa SG, Liberman MC. (2009). Adding insult to injury: cochlear nerve degeneration after “temporary” noise-induced hearing loss. J Neurosci 2009;29:14077–14085. https://blogs.cdc.gov/niosh-science-blog/2014/11/21/tts-screening/
- Heeringa AN, van Dijk P. (2014). The dissimilar time course of temporary threshold shifts and reduction of inhibition in the inferior colliculus following intense sound exposure. Hear Res. 2014;312:38–47. https://www.ncbi.nlm.nih.gov/pubmed/24650953
- Liberman MC, Epstein MJ, Cleveland SS, et al. (2016) Toward a Differential Diagnosis of Hidden Hearing Loss in Humans. PLoS One;11:e0162726. https://www.ncbi.nlm.nih.gov/pubmed/27618300
- Moser T, Starr A. (2016) Auditory neuropathy–neural and synaptic mechanisms. Nat Rev Neurol.;12:135–49. https://www.ncbi.nlm.nih.gov/pubmed/26891769
- Nordmann AS, Bohne BA, Harding GW. (2000). Histopathological differences between temporary and permanent threshold shift. Hear Res. 2000;139:13–30. https://www.ncbi.nlm.nih.gov/pubmed/10601709
- Shi L, Chang Y, Li X, et al. (2016). Cochlear Synaptopathy and Noise-Induced Hidden Hearing Loss. Neural Plast. 2016;2016:6143164. https://www.hindawi.com/journals/np/2016/6143164/
- Themann, C. (Nov. 24, 2014) CDC NIOSH Science Blog: First, Do No Harm: Temporary Threshold Shift Screening is Not Worth the Risk. https://blogs.cdc.gov/niosh-science-blog/2014/11/21/tts-screening/