Marinus Pharmaceuticals Reports Preliminary Fourth Quarter and Full Year 2023 ZTALMY Net Product Revenue and Provides Business Update

Marinus Pharmaceuticals, Inc. (Nasdaq: MRNS), a pharmaceutical company dedicated to the development of innovative therapeutics to treat seizure disorders, today reported business highlights and preliminary U.S. ZTALMY net product revenue for the fourth quarter and year ended December 31, 2023.

“Our commercial strategy and deep understanding of the epilepsy and rare disease space continues to drive increasing adoption of ZTALMY, establishing a strong foundation for the future of the franchise and positioning us to generate robust growth in the year ahead,” said Scott Braunstein, M.D., Chairman and Chief Executive Officer of Marinus. “We expect 2024 will be another pivotal year for Marinus with two Phase 3 data readouts anticipated, beginning with topline data from the RAISE trial of IV ganaxolone in refractory status epilepticus in the second quarter followed by the TrustTSC study readout in tuberous sclerosis complex in the third quarter. We have an opportunity to address significant unmet needs in patients with refractory seizure disorders and remain committed to developing potentially lifesaving treatments.”

ZTALMY

• Continued to execute U.S. commercial launch of ZTALMY (ganaxolone) oral suspension CV, resulting in preliminary unaudited net product revenue of between $6.5 and $6.7 million for the fourth quarter of 2023 and between $19.5 and $19.7 million for the fiscal year ended December 31, 2023
• Continued growth in commercial patients with more than 165 patients active on therapy at the end of 2023
• Full year 2024 projected U.S. ZTALMY net product revenues of between $32 and $34 million
• Orion Corporation continues to prepare for commercial launches of ZTALMY in select European countries in 2024

Pipeline Update

Status Epilepticus

• Over 90% of the 82 patients required for an interim analysis are now enrolled in the Phase 3 RAISE trial of intravenous (IV) ganaxolone in refractory status epilepticus (RSE)
  • Continue to expect enrollment for the interim analysis to conclude in the first quarter of 2024 with topline data anticipated in the second quarter of 2024, assuming pre-defined stopping criteria for the interim analysis are met
• To date, 26 patients with super refractory status epilepticus (SRSE) have been treated with IV ganaxolone under eINDs

Ganaxolone development in the RAISE trial is being funded in part by the Biomedical Advanced Research and Development Authority (BARDA), part of the Administration for Strategic Preparedness and Response at the U.S. Department of Health and Human Services, under contract number 75A50120C00159.