Marinus Pharmaceuticals, Inc. (Nasdaq: MRNS), a pharmaceutical company dedicated to the development of innovative therapeutics to treat epilepsy and other neuropsychiatric disorders, today announced clinical and regulatory updates for its orphan seizure programs in tuberous sclerosis complex (TSC), CDKL5 deficiency disorder (CDD) and PCDH19-related epilepsy (PCDH19-RE).

Tuberous Sclerosis Complex Program

“The decision to expand our epilepsy program in TSC was strategically informed by the discovery of a new potential epilepsy biomarker, Allo-S, in our Phase 2 study in PCDH19-related epilepsy,” said Scott Braunstein, M.D., Chief Executive Officer of Marinus. “This led us to additional analyses that identified TSC as another rare genetic disorder that may be similarly impacted by Allo-S levels. We look forward to initiating a Phase 2 trial in the first half of 2020 to provide a potential targeted treatment option for these patients with limited approved therapies.”

Marinus intends to initiate a Phase 2, open label study to evaluate the safety and tolerability of adjunctive ganaxolone treatment in patients with seizures associated with TSC. Patient stratification from the Company’s PCDH19-related epilepsy Phase 2 trial identified a subpopulation of patients with improved ganaxolone responses, those with low levels of allopregnanolone-sulfate (Allo-S). Based on these data, the Company performed a biomarker analysis to identify other rare genetic epilepsies that may benefit from the GABAA-receptor modulatory effects of ganaxolone and today announced TSC as the next planned orphan epilepsy program to study the effect of ganaxolone on seizures as well as the expanded utility of a potential biomarker.

The planned Phase 2 study will be conducted at approximately 4-6 sites in the United States and enroll approximately 20-40 patients ages 2 to 65. Patients will undergo a 4-week baseline period followed by a 12-week treatment period. The primary endpoint for the study is percent change in 28-day primary seizure frequency through the end of the 12-week treatment period relative to the 4-week baseline period.

CDKL5 Deficiency Disorder (CDD) Program

The European Medicines Agency (EMA) has granted orphan drug designation for ganaxolone for the treatment of CDD. EMA orphan designation status is assigned to medicines intended to treat rare conditions and allows recipient companies to benefit from incentives offered by the European Union to develop medicines for the treatment, prevention or diagnosis of a life-threatening or chronically debilitating rare disease.

Dr. Braunstein continued, “Receiving Orphan Drug Designation for our CDD program from the EMA is an important regulatory milestone as we advance ganaxolone through our pivotal Phase 3 Marigold study. We are proud of our continued progress and execution, with strong trial enrollment, and look forward to sharing topline data in Q3 2020.”

Marinus is currently in the final stages of recruiting for the Marigold Study, its pivotal Phase 3 study evaluating the use of oral ganaxolone in children and young adults with CDD, a refractory form of pediatric epilepsy with no currently approved treatments. The global, double-blind, placebo-controlled, pivotal study will enroll up to 100 patients between the ages of 2 and 21 with a confirmed disease-related CDKL5 gene variant. Enrollment in the study continues to progress as planned and the Company remains on-track to report top-line data in Q3 2020.

PCDH19-related Epilepsy (PCDH19-RE) Program

International site initiation and enrollment is continuing in the Violet Study, a single pivotal Phase 3 study evaluating oral ganaxolone in children with PCDH19-RE. The study will enroll up to 70 patients between the ages of 1 and 17 with a confirmed PCDH19 mutation. Patients are stratified into biomarker positive and negative groups, which could potentially provide the epilepsy community with the first diagnostic blood test that predicts the likelihood of a treatment response. The Company remains on-track to report top-line data in 2021.