Indivior is picking up a small molecule allosteric modulator designed to treat substance use disorder from Addex Therapeutics, providing the latter the chance to make up to $300 million in biobucks, plus royalties.
The clinical candidate selection is part of a broader pact Indivior and the neurological disorder-focused biotech inked back in 2018. At the time, the licensing and research agreement focused on the worldwide development and commercialization of investigational positive allosteric modulator (PAM) ADX71441 for the treatment of addiction. Those plans haven’t exactly panned out, with the program “under evaluation,” according to Addex’s pipeline website.
As part of the 2018 Indivior deal, the U.S. pharma paid out $5 million upfront, with $4 million tacked on for an Addex research program designed to discover more PAM compounds that trigger GABA responses at the GABAB receptor. Indivior also offered up $330 million in potential milestones for Addex.
Now, Indivior has opted to take on all future development in substance use disorder for an unnamed compound emerging from the partnership. Under the terms of the agreement, Addex has also chosen to advance its own independent GABAB PAM program sourced from the same collaboration. That candidate will take aim at treating chronic cough.
“The selection of GABAB PAM clinical candidates is the culmination of more than five years of research at Addex in close collaboration with the team at Indivior. During this time, we were able to pinpoint specific candidates from thousands of compounds using the power of our industrial-scale allosteric modulator discovery platform,” Addex CEO Tim Dyer said in an Aug. 27 release.
The biotech will now focus on progressing the cough candidate into preclinical studies that would allow for the company to submit a request to the FDA to begin in-human testing.
Addex’s stock has shot up 38% since market close yesterday, hitting $10.36 per share at 10:30 a.m. ET today compared to $7.49 at market close yesterday.
The Indivior announcement is particularly good news for the biotech after J&J discontinued development of an Addex-partnered epilepsy drug in July.
In late April, Addex revealed that the PAM program, which emerged from a 2004 collaboration between Addex and J&J’s Janssen unit, had failed to reduce the occurrence of seizures in a phase 2 trial. Dubbed ADX71149, the candidate has now been cleared from both the Big Pharma’s and Switzerland-based biotech’s pipelines.
The neuro company has another clinical-stage asset in the works: a mGlu5 negative allosteric modulator called dipraglurant. The program has had its own struggles, with Addex revealing in 2022 that a mid-stage trial designed to spearhead its expansion into muscle spasm disorders delivered “inconclusive” data. A Parkinson’s study was planned, but COVID-19 headwinds blew that off course as well.
Addex is now evaluating dipraglurant as a potential treatment for post-stroke/traumatic brain injury recovery.