Addex and Indivior Select GABAB Positive Modulator Candidates

Geneva, Switzerland, August 27, 2024 - Addex Therapeutics (SIX/NASDAQ: ADXN), a clinical-stage biopharmaceutical company, and Indivior PLC (NASDAQ/LSE: INDV) have announced the selection of clinical candidates from their collaborative research on GABAB positive allosteric modulators (PAM). Indivior has chosen a compound for further development in treating substance use disorder and will now lead all future development efforts for this compound. According to the agreement, Addex stands to receive up to USD 330 million upon achieving certain regulatory, clinical, and commercial milestones, along with tiered royalties ranging from high single digits to low double digits based on net sales.

Addex has decided to advance a compound from the same GABAB PAM program for the treatment of chronic cough independently. Christian Heidbreder, Chief Scientific Officer at Indivior, praised the collaboration, stating that it has been vital in identifying a promising candidate for treating substance use disorders. He emphasized that targeting the GABAB receptor with positive allosteric modulators presents a potentially new method for developing much-needed therapies, particularly in the complex field of addiction treatment.

Tim Dyer, CEO of Addex, highlighted that the selection of GABAB PAM clinical candidates is the result of over five years of collaborative research. Using their large-scale allosteric modulator discovery platform, they successfully focused on specific candidates from thousands of compounds. Dyer expressed enthusiasm for advancing their selected candidate for chronic cough into IND enabling studies while supporting Indivior in the substance use disorder program's next steps.

GABAB receptor activation through positive allosteric modulation has been clinically and commercially validated. Baclofen, a generic GABAB receptor agonist used for spasticity, has shown efficacy in various other conditions, including alcohol use disorder, CMT1A, overactive bladder, chronic cough, and pain. Despite its effectiveness, baclofen's broader use is limited due to side effects, rapid clearance, and the development of tolerance. Novel PAMs that enhance GABA responses rather than acting as orthosteric agonists at the GABAB receptor are anticipated to offer efficacy with fewer side effects. PAMs are advantageous as they act only when the natural ligand (GABA) activates the receptor, potentially leading to less tolerance compared to direct agonists.

Addex Therapeutics is dedicated to developing a range of novel small molecule allosteric modulators for neurological disorders. Their lead drug candidate, dipraglurant, an mGlu5 negative allosteric modulator (NAM), is being evaluated for brain injury recovery, including post-stroke and traumatic brain injury recovery. Indivior, Addex's partner, has selected a GABAB PAM drug candidate for substance use disorders, with plans to commence IND enabling studies in the first half of 2025. Addex is also advancing its own GABAB PAM program for chronic cough, aiming to start IND enabling studies in 2025.

Additionally, Addex holds a 20% equity interest in Neurosterix LLC, a private company progressing a portfolio of allosteric modulator programs, including M4 PAM for schizophrenia, mGlu7 NAM for mood disorders, and mGlu2 NAM for mild neurocognitive disorders. Addex shares are listed on the SIX Swiss Exchange, and American Depositary Shares representing its shares are listed on the NASDAQ Capital Market under the ticker symbol "ADXN."

How to obtain the latest research advancements in the field of biopharmaceuticals?

In the Synapse database, you can keep abreast of the latest research and development advances in drugs, targets, indications, organizations, etc., anywhere and anytime, on a daily or weekly basis. Click on the image below to embark on a brand new journey of drug discovery!