ConSynance Therapeutics, Inc. has been granted Rare Pediatric Disease Designation (RPDD) by the U.S. Food and Drug Administration (FDA) for CSTI-500, an investigational drug intended for the treatment of Prader-Willi Syndrome (PWS) in children and adolescents. This regulatory milestone supports ConSynance's preparations for a Phase 2 study of CSTI-500, planned to commence in 2025.
Significance of RPDD
The FDA grants RPDD for diseases affecting fewer than 200,000 individuals in the U.S., which are serious or life-threatening and primarily affect those under 18 years of age. Shuang Liu, PhD, Founder and CEO of ConSynance, emphasized the importance of this designation, noting that CSTI-500 is the first drug candidate designed to address both hyperphagia and severe temper outbursts associated with PWS, offering a potential breakthrough treatment.
About CSTI-500
CSTI-500 is a Phase 2-ready, first-in-class, orally administered Triple Monoamine Reuptake Inhibitor (TRI). It is designed to increase the levels of serotonin, dopamine, and norepinephrine in the synaptic clefts of neurons. PWS is associated with low levels of these neurotransmitters, and CSTI-500 has demonstrated brain target engagement in healthy volunteers via positron emission tomography (PET). These data, along with pharmacokinetics data, predict the efficacy of CSTI-500 in PWS and other neuropsychiatric indications, enabling a personalized dosing approach to ensure optimal safety and efficacy. CSTI-500 has been studied in nearly 100 humans across three Phase 1 clinical trials, including 10 PWS patients.
Prader-Willi Syndrome (PWS)
PWS is a rare, complex genetic neurodevelopmental disorder affecting approximately 1 in 15,000 live births. It is characterized by severe hypotonia and failure to thrive, evolving into life-threatening hyperphagia and neuropsychiatric behaviors, including severe temper outbursts. There are currently no approved therapies that address the core dysfunctional brain networks associated with abnormal levels of monoamines in PWS. Normalizing these neurotransmitters may restore functional neural circuits, alleviating hyperphagia, temper outbursts, and other behavioral symptoms.
Financial Implications
The RPDD makes ConSynance eligible to receive a transferable Priority Review Voucher if CSTI-500 receives FDA approval for PWS. Priority Review Vouchers have recently sold for approximately $100 million, highlighting their significant value.
