Clinical-stage Programs


CSTI-500 is an oral, once-per-day serotonin, dopamine and norepinephrine reuptake inhibitor, or a triple reuptake inhibitor  (“TRI”). It is under development for the treatment of hyperphagia in PWS, and for hypothalamic-injury induced obesity. CSTI-500 addresses the dysregulated neurotransmission in the key brain centers in PWS and hypothalamic injury-induced obesity. It is an optimally balanced triple reuptake inhibitor with unique pharmacological features that allow for predictable and safe titration to an efficacious dose tailored to the individual patient. CSTI-500 has the potential to provide a transformative therapy, not only for hyperphagia and obesity but also for many of the psychiatric co-morbidities in both diseases.

CSTI-500 was generally safe and well-tolerated and has a half-life of 50 hours in Phase I clinical trials. Also importantly, it demonstrated CNS target engagement via positron emission tomography (PET) that predicts efficacy in patients.


ConSynance holds the exclusive global rights to CSTI-500.


Partnered Program - HBS-102 (formerly CSTI-100) 


Harmony Biosciences holds the full development and commercialization rights globally, with the exception of Greater China.  ConSynance holds the development and commercialization rights in Greater China.​

HBS-102 is an investigational compound being developed as a potential treatment for narcolepsy and other rare neurological diseases. HBS-102 is a potential first-in-class molecule with a novel mechanism of action which targets melanin concentrating hormone (MCH) neurons in the hypothalamus, which make up the control center for REM sleep and related behaviors. In the setting of orexin deficiency (as occurs in patients with type 1 narcolepsy), there is an imbalance between orexin and MCH which could result in the control center for REM sleep going unchecked that could lead to REM sleep intruding into wakefulness. If that occurs, the clinical symptoms are experienced as cataplexy, hallucinations, and/or sleep paralysis. HBS-102, an MCHR1 antagonist, blocks the activity of the MCH neurons, which could potentially reduce REM intrusions into wakefulness and therefore reduce the debilitating symptoms of cataplexy, hallucinations and sleep paralysis.