Opportunity
Tinnitus, the perception of sound without an external source, is a prevalent and burdensome medical condition affecting over 10% of the global adult population, with estimates indicating hundreds of millions of sufferers worldwide, including approximately 50 million in the United States and 130 million in China. Its prevalence is expected to rise due to factors such as aging populations, increased occupational and leisure noise exposure, and its status as a common sequela of modern warfare. Current primary treatments, including sound therapy and cognitive behavioral therapy (CBT), offer only symptomatic relief and do not provide a cure. While treatments like repetitive transcranial magnetic stimulation (rTMS) and deep brain stimulation (DBS) target neural plasticity, they are often invasive, lack flexibility, and have suboptimal biocompatibility. Critically, there is currently no drug specifically approved by regulatory bodies like the U.S. FDA for the effective treatment or cure of tinnitus. This significant unmet medical need and the growing global market, driven by demographic trends, create a substantial opportunity for developing novel, effective, and safe pharmacological interventions.
Technology
This patent discloses innovative methods for alleviating or treating tinnitus by administering a CCK-B receptor agonist, such as the compounds HT-267 or CCK-4. The technology is grounded in the discovery that activating the cholecystokinin B receptor (CCKBR) in the auditory pathway can induce neural plasticity, specifically long-term potentiation (LTP), which is crucial for auditory processing. The invention demonstrates that CCK-B receptor agonists, particularly HT-267, can rescue or induce LTP in the thalamocortical auditory pathway, a process dependent on CCK signaling. HT-267, a modified CCK-4 analog with a halogen-bromine substitution, exhibits superior stability, higher affinity for CCKBR, better blood-brain barrier penetration, a longer elimination half-life in the brain, and higher potency compared to CCK-4. The method can involve administering the agonist (e.g., via oral, intraperitoneal, or intravenous routes) optionally combined with sound exposure. Preclinical studies in a noise-induced tinnitus mouse model show that HT-267, especially when combined with sound therapy, significantly reduces tinnitus-associated behaviors as measured by Gap-Prepulse Inhibition of the Acoustic Startle (GPIAS) reflex across multiple frequencies, indicating effective alleviation of tinnitus symptoms.
Advantages
- Provides a novel pharmacological target (CCK-B receptor) for treating tinnitus, addressing a major unmet medical need.
- Offers a potential cure or significant alleviation, unlike current therapies that mainly manage symptoms.
- CCK-B receptor agonists like HT-267 have high specificity for CCKBR, which is less widely distributed in the brain than other targets (e.g., NMDA receptors), potentially leading to fewer side effects.
- HT-267 demonstrates favorable pharmacokinetics: good blood-brain barrier penetration, oral bioavailability, high brain uptake, and a long half-life in the brain for sustained effect.
- The treatment can be non-invasive (e.g., oral administration) and flexible, improving patient compliance compared to invasive brain stimulation techniques.
- Combination therapy with sound exposure may enhance therapeutic efficacy, as shown in animal models.
Applications
- Development of pharmaceutical drugs for the treatment and prevention of tinnitus in human patients.
- Formulation of CCK-B receptor agonists (like HT-267 or CCK-4) into various dosage forms: powders, solutions, suspensions for oral, intraperitoneal, or intravenous administration.
- Use in combination therapy regimens integrating drug administration with structured sound exposure or acoustic therapy protocols.
- Potential application in treating conditions related to auditory pathway dysfunction or maladaptive neural plasticity.
- Serving as a research tool for studying the role of CCK signaling and neural plasticity in the auditory system and related disorders.
