Partnered Programmes
Further details on partnered drug discovery programmes

Oral Orexin-1 receptor antagonist programme for the treatment of Substance Abuse Disorders

We have successfully out-licensed our novel, oral Orexin-1 receptor antagonist (C4X_3256) to addiction market leaders Indivior, generating $10 million upfront and up to $284 million of potential development, regulatory and commercialisation milestones, in addition to royalties. Prior to deal signature, the pivotal pre-clinical GLP safety and toxicology studies were completed successfully and our partner Indivior is progressing this investigational drug towards initiation of the first clinical studies.


The Orexin-1 receptor is considered to be central to the brain’s “craving” and “reward” pathways with pre-clinical efficacy observed in multiple addiction models. Prior to the licensing deal with Indivior, we demonstrated that C4X_3256 attenuated cocaine-induced brain dopamine elevation supporting its potential in this important therapeutic area and adding to the compelling pre-clinical efficacy data already achieved in nicotine addiction showing reductions in self-administration and re-instatement.

In addition, our C4X_3256 programme was awarded a grant from the National Institute on Drug Abuse (“NIDA”, a division of National Institute of Health (“NIH”)) to support the investigation of the effects of C4X_3256 in cocaine addiction efficacy models extending the pre-clinical pharmacology package in parallel with clinical development.