Neurocrine's $45M bet goes 0 for 2 with rare epilepsy flop following negative essential tremor trial

Neurocrine Biosciences’ $45 million rare pediatric epilepsy bet has fallen at an early clinical hurdle. Thirty months after licensing the selective T-type calcium channel inhibitor, the biotech has reported its second setback in quick succession with the failure to beat placebo in a small phase 2 clinical trial. 

Idorsia took the drug candidate, now known as NBI-827104, into the clinic on the strength of evidence that the molecule can enter the brain and block channels associated with epilepsies. Neurocrine came on board in 2019, initially paying a $5 million fee to form a collaboration and then handing over a further $45 million to take up its option on the program.

San Diego-based Neurocrine hustled the asset into a phase 2 trial in pediatric epileptic encephalopathy with continuous spike-and-wave during sleep within months of taking up its option. The trial randomized 24 children to receive either NBI-827104 or placebo orally for 13 weeks.

Neurocrine designed the clinical trial to show whether the molecule affects spike-in-waves, a continuous or nearly continuous EEG pattern seen during the non-rapid eye movement phase of sleep in patients with the rare epilepsy. The condition is associated with cognitive, language, behavioral or motor regression or stagnation.

NBI-827104 was statistically no better than placebo at improving the ratio of spike-wave index by Week 6, causing the study to miss its primary endpoint. Neurocrine is yet to share data from the study but previously said a 50% reduction in the index would be very clinically relevant for patients with the rare condition, who are currently treated with drugs including steroids.

In a statement, Eiry Roberts, M.D., chief medical officer at Neurocrine, said the company is continuing to “analyze the rich data set generated from this study to determine next steps.” The statement is devoid of positive news on the efficacy front, with the only silver lining revealed to date being the fact that the candidate was generally well tolerated. Neurocrine recently stopped essential tremor work on the drug.

Shares in Neurocrine slipped 5% to $115 after-hours. The muted response reflects the importance of the candidate to Neurocrine, a company with a blockbuster product in Ingrezza and a pipeline that features multiple other mid- and late-phase programs.