Addex regains rights to addiction drug candidate from Indivior
Swiss biotech Addex Therapeutics has regained global rights to a GABA-B drug portfolio from Indivior, including a candidate for substance use disorders that has completed studies needed before a Phase 1 trial. Indivior ended the collaboration as it reorganizes R&D ahead of its proposed merger with Supernus Pharmaceuticals.
Why it matters: Addex gets back the candidate and related intellectual property without paying Indivior. “There were no payments or financial considerations on the return and no obligations on either side,” an Addex spokesperson told European Biotechnology.
The backstory: Indivior paid Addex $5 million upfront under the 2018 agreement. According to Addex, it “then funded research at Addex for more than $20 million”. Addex also spent an estimated equivalent amount internally to develop the drug. Indivior selected the current candidate in 2024 and completed the studies required to support a clinical trial application in 2025. The partnership had originally included another candidate, ADX71441, whose development Indivior stopped in 2019.
How it works: GABA helps put the brakes on nerve activity. Activating its GABA-B receptor can dampen signaling in the brain’s reward circuits. Animal studies suggest this may reduce the rewarding effects of addictive drugs and drug-seeking behavior. Baclofen, a medicine for muscle spasticity, activates that receptor directly but can cause sedation.
- Addex’s compounds instead strengthen the receptor’s response to the body’s own GABA, with the aim of limiting those side effects. Whether the returned candidate can help people with substance use disorders remains untested.
What’s next: In its half-year results, Addex says it will seek clearance to start Phase 1 “subject to securing funding or a development partner”. Its separate GABA-B candidate for chronic cough also depends on funding or a partner before it begins studies needed for a clinical trial application.
- Addex held CHF 767,328 (about €812,000) in cash on June 30. It subsequently raised $2.8 million (about €2.5 million) through share sales and says its cash should fund operations through the fourth quarter of 2027. The interim report nevertheless flags substantial doubt about its ability to continue as a going concern and says advancing its programs depends on further capital or collaborations.
What to watch: Addex just won back a Phase 1-ready asset without having to pay fully for its development but whether this drug moves into human trials will depend on Addex finding a new partner or raising enough capital to finance further development.
