Monday, Addex Therapeutics (NASDAQ:ADXN) announced its partner Janssen Pharmaceuticals, Inc, a unit of Johnson & Johnson (NYSE:JNJ), has discontinued the development of ADX71149 (JNJ-40411813) in epilepsy.

The partnership between the two companies remains ongoing while the full data set from the Phase 2 study of ADX71149 (JNJ-40411813) as an adjunctive epilepsy treatment is analyzed.

The decision follows top-line Phase 2 data announced in April, showing that adjunctive ADX71149 (JNJ-40411813) administration in patients with focal onset seizures with suboptimal response to levetiracetam or brivaracetam did not achieve statistical significance for the primary endpoint of time for patients to reach baseline seizure count when ADX71149 was added to standard of care.

After the data, Addex Therapeutics stock tumbled almost 50%.

"Following the Phase 2 study results in epilepsy, this decision was anticipated. We have had an excellent working relationship with Janssen for twenty years and will continue to work diligently to complete the analysis of the full Phase 2 data set to elucidate all learnings from the study," said Tim Dyer, CEO of Addex. "Once we have that information in hand, we anticipate a decision on the future of this asset."

Price Action: ADXN stock is down 1.36% at $7.99 during the premarket session at last check Monday.

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