Marinus Pharmaceuticals (MRNS) 2024 Cantor Fitzgerald Global Healthcare Conference summary

Key achievements and product performance

• Ztalmy has been on the market for over two years, with more than 200 patients currently on therapy and over 70% retention, demonstrating strong durability and positive impact on quality of life for CDKL5 patients.

• Completion of a $40 million trial in TSC patients who failed multiple prior antiepileptics, positioning for a new indication and market expansion.

• Real-world data and case reports indicate no loss of efficacy over time, with improved outcomes linked to better education, dosing, and manufacturing processes.

• The drug's unique pan-extrasynaptic activity is believed to contribute to its durable efficacy and potential neuroprotective effects.

• Patient and caregiver experiences highlight both seizure reduction and broader quality-of-life improvements.

Clinical trial design and learnings

• The TRUST-TSC phase III study uses a median-based primary endpoint to minimize outlier effects, targeting a clinically meaningful seizure reduction of over 40%.

• A revised titration schedule, based on pharmacokinetic data, improved tolerability and reduced discontinuation rates to under 7%.

• Over 90% of patients have rolled over to the open-label phase, indicating strong engagement and perceived benefit.

• The study is powered at 90% to detect a 25% median difference in seizure reduction, with a placebo rate expected around 10%.

• More than half of the 130 patients are on mTOR inhibitors, supporting broad applicability and safe use with standard care.

Commercial and regulatory outlook

• The TSC market represents a significant expansion opportunity, with seizures as the primary concern for patients and caregivers.

• A modest doubling of the sales force is planned to target 72 key centers and reach the majority of 12,700 refractory TSC patients.

• The company aims to harmonize the titration schedule across indications for improved safety and efficacy.

• NDA submission for TSC is targeted by March-April, with potential approval by October 1; European filing will follow after three additional months of open-label data.

• The commercial team is optimistic about market penetration due to limited drug-drug interactions and strong physician alignment.