Addex Therapeutics: Phase 2 epilepsy study of ADX71149 fails to meet primary endpoint

Addex Therapeutics, a clinical-stage biopharmaceutical company, disclosed phase 2 epilepsy study results for adjunctive ADX71149 (JNJ-40411813) in patients with inadequate response to levetiracetam or brivaracetam. The study didn't meet statistical significance for the primary endpoint of time to reach baseline seizure count when adding ADX71149 to standard care.

Data included 110 patients, receiving 50 mg or 100 mg of ADX71149 twice daily (or 100 mg or 200 mg twice daily for those on CYP3A4 inducing anti-seizure medication) alongside standard treatments. ADX71149 adjunctive administration proved safe and well-tolerated.

ADX71149 selectively modulates metabotropic glutamate subtype 2 (mGlu2) receptors. The study assessed efficacy, safety, tolerability, and pharmacokinetics in focal onset seizure patients with inadequate responses to levetiracetam or brivaracetam. Glutamate, the brain's primary excitatory neurotransmitter, plays a pivotal role in seizure initiation and spread. Activating mGlu2 receptors reduces glutamate release, potentially restoring neurotransmitter balance during seizures. Despite progress, epilepsy management remains a significant unmet medical need for many patients.