Sound Pharma to present positive interim data from its Phase 2b Cystic Fibrosis STOP Ototoxicity Trial

By January 30, 2024News Short

Sound Pharmaceuticals (SPI) will present the Phase 2b STOP Ototoxicity data that was selected for podium presentation at the Association for Research in Otolaryngology (ARO) Midwinter Meeting in Anaheim, CA (February 3-7).

This initial safety and efficacy study of SPI-1005 (ebselen) to prevent and treat aminoglycoside-induced ototoxicity enrolled 60 adult CF patients undergoing intravenous (IV) tobramycin for the treatment of acute pulmonary exacerbation. Ototoxicity (hearing loss, tinnitus, vertigo or dizziness) is a common side effect of aminoglycoside antibiotics (tobramycin, amikacin, gentamycin and streptomycin). Currently, there are no FDA approved therapies for the prevention/treatment of aminoglycoside ototoxicity or the treatment of any other type of sensorineural hearing loss, tinnitus, or dizziness.

In the Phase 1b observational study (N=20), SPI reported that a 14-day course of IV tobramycin resulted in ototoxicity rates of 89% and 93%, at 2 and 4-weeks after aminoglycoside treatment was completed (Harruff, Journal of Cystic Fibrosis, 2021). In the Phase 2b interventional study, adult patients were randomized in a double blinded fashion to 3 different doses of ebselen or placebo, taken orally for 21 days within 3 days of starting IV tobramycin. In the Phase 2b study (N=40), the ototoxicity rates were 73% and 63%, at 2 and 4-weeks after aminoglycoside treatment was completed, a statistically significant reduction when compared to the Phase 1b study (p-value <0.05). No significant differences in age, duration of IV tobramycin, concomitant medications, respiratory status, or baseline hearing loss were observed between the studies.

Interim analysis of the Phase 2b results shows a dose proportional decrease in the ototoxicity rate (from placebo, 200, 400, to 600 mg ebselen), with the 400 and 600 mg dose having ototoxicity rates of 44% and 43% at 4-weeks (400 mg, p-value <0.05). “To our knowledge, these are the first positive results of an ototoxicity intervention trial in humans undergoing antibiotic treatment for pulmonary exacerbation,” said Jonathan Kil, MD, SPI’s Co-Founder and CEO. Results from two other preclinical studies involving ebselen treatment, a novel anti-inflammatory compound that has also shown positive results in clinical trials involving acute noise exposure, bipolar mania, and Meniere’s disease, will be presented at the ARO.

The CFF provided a $2.2M Therapeutic Development Award to SPI to support the studies. Details of this trial (NCT02819856) can be viewed online at , or by visiting