Phenotypic Optimization of Urea-Thiophene Carboxamides To Yield Potent, Well Tolerated, and Orally Active Protective Agents against Aminoglycoside-Induced Hearing Loss.
Sarwat ChowdhuryKelly N OwensR Jason HerrQin JiangXinchao ChenGraham JohnsonVincent E GroppiDavid W RaibleEdwin W RubelJulian A SimonPublished in: Journal of medicinal chemistry (2017)
Hearing loss is a major public health concern with no pharmaceutical intervention for hearing protection or restoration. Using zebrafish neuromast hair cells, a robust model for mammalian auditory and vestibular hair cells, we identified a urea-thiophene carboxamide, 1 (ORC-001), as protective against aminoglycoside antibiotic (AGA)-induced hair cell death. The 50% protection (HC50) concentration conferred by 1 is 3.2 μM with protection against 200 μM neomycin approaching 100%. Compound 1 was sufficiently safe and drug-like to validate otoprotection in an in vivo rat hearing loss model. We explored the structure-activity relationship (SAR) of this compound series to improve otoprotective potency, improve pharmacokinetic properties and eliminate off-target activity. We present the optimization of 1 to yield 90 (ORC-13661). Compound 90 protects mechanosensory hair cells with HC50 of 120 nM and demonstrates 100% protection in the zebrafish assay and superior physiochemical, pharmacokinetic, and toxicologic properties, as well as complete in vivo protection in rats.
Keyphrases
- hearing loss
- induced apoptosis
- cell cycle arrest
- cell death
- public health
- randomized controlled trial
- oxidative stress
- diabetic rats
- endoplasmic reticulum stress
- pseudomonas aeruginosa
- cystic fibrosis
- emergency department
- structure activity relationship
- drug induced
- working memory
- single cell
- multidrug resistant
- endothelial cells
- anti inflammatory