Marinus tanks as adult focal onset seizure drug fails late stage

Marinus Pharmaceuticals Inc said it plans to stop development of its treatment for drug-resistant focal onset seizures in adults after it failed a late-stage trial, sending the company’s shares plunging 60 percent in premarket trading.

The study testing the drug, ganaxolone, missed the main goal of significantly reducing frequency in the occurrence of seizures, the company said on Monday.

Epileptic seizures require chronic treatment, often over a lifetime. Despite the many available antiepileptic drugs, about 30 to 35 percent of patients do not attain acceptable seizure control either with single drug or multiple drug therapy.

Ganaxolone is being developed in three different dose forms: intravenous, capsule and liquid in an attempt to provide options for patients who do not react to presently available antiepileptics.

Marinus said it will continue to develop ganaxolone in status epilepticus, a condition where seizures last for too long and often recur in a short span of time, and in pediatric orphan indications.

About 44 patients on ganaxolone dropped out of the study, compared with 26 in the placebo group, most commonly due to adverse events such as dizziness, fatigue and drowsiness, the company said.

Marinus’ shares were trading at $2.15 before the bell. Up to Friday’s close of $5.34, the stock had lost 30 percent of its value this year.

(Reporting by Amrutha Penumudi in Bengaluru; Editing by Sriraj Kalluvila)