Marinus Pharmaceuticals Provides Pipeline Update - June 30, 2020

• Status Epilepticus pivotal Phase 3 trial on-track to begin in Q3 2020
• CDKL5 Deficiency Disorder Phase 3 trial results in Q3 2020
• First patient enrolled in Phase 2 Tuberous Sclerosis Complex trial
• Enrollment in PCDH19 proof-of-concept trial increases to 25-30 patients
• Pipeline update webinar featuring four KOLs today at 8:00am ET

RADNOR, Pa., June 30, 2020 (GLOBE NEWSWIRE) --Marinus Pharmaceuticals, Inc. (Nasdaq: MRNS), a pharmaceutical company dedicated to the development of innovative therapeutics to treat rare seizure disorders, today provided a pipeline update in advance of it clinical and commercial overview webinar to be held today, Tuesday, June 30, 2020 from 8am – 10:30am Eastern Time.

“With a final protocol in place, we are on-track to begin our Phase 3 pivotal trial in status epilepticus next quarter,” said Scott Braunstein, M.D., Chief Executive Officer of Marinus. “Our Phase 3 trial is designed to demonstrate both rapid onset of antiepileptic activity along with sustained status cessation, allowing physicians to focus their attention on the patients’ underlying disease state and avoid the often devastating consequences of uncontrolled SE and anesthesia induced coma.”

Dr. Braunstein added, “Our oral ganaxolone program has focused on rare genetic epilepsies with a biology-driven scientific foundation underserved by current available treatment options. To that end, we have initiated a Phase 2 study in tuberous sclerosis complex-related epilepsy and are preparing for our Phase 3 data readout in CDD next quarter. We look forward to sharing further details on our clinical and commercial strategies during our pipeline update event today and are thrilled to have KOL engagement and insight as we discuss our programs.”

Pipeline Update:

Status Epilepticus (SE)

• Marinus has finalized the protocol for its planned Phase 3 pivotal clinical trial in SE following its End of Phase 2 Meeting held in March 2020 and based on the successful results from its completed Phase 2 trial.
• The Phase 3 study will be a randomized, double-blind, placebo-controlled trial in SE patients who have failed benzodiazepines and 2 or more intravenous anti-epileptic drugs (AEDs).
• The trial will enroll 124 patients randomized to receive ganaxolone or placebo adjunctive to standard of care at approximately 80-100 U.S. sites.
• Patients will receive a 36-hour infusion followed by a 12-hour taper for a total 48-hour treatment period, which, for patients randomized to receive ganaxolone, targets a plasma concentration of greater or equal to 500ng/mL for 12-hours (same target concentration, 50% longer duration as the Target Dose evaluated in Phase 2).
• The co-primary endpoints for the study are (i) proportion of patients with SE cessation within 30 minutes of treatment initiation without medications for the acute treatment of SE and (ii) proportion of patients with no progression to IV anesthesia for 36 hours following treatment initiation.
• Trial initiation on-track for Q3 2020 with topline data expected first half of 2022

CDKL5 Deficiency Disorder (CDD)

• Marinus remains on-track to report top‑line data from the pivotal Phase 3 Marigold Study, which is evaluating the use of oral ganaxolone in children and young adults with CDD. The global, double‑blind, placebo‑controlled, clinical trial has enrolled 101 patients between the ages of 2 and 21 with a confirmed disease‑related CDKL5 gene variant.
• In advance of topline data, Marinus has begun preparations for an expanded access program (EAP) in CDD that will allow the Company, on positive data, to offer ganaxolone to patients who were unable to participate in the Phase 3 study.

Tuberous Sclerosis Complex (TSC)

• The first patient has been enrolled in the Company’s Phase 2 open‑label trial to evaluate the safety and tolerability of adjunctive ganaxolone treatment in patients with TSC. The trial is expected to enroll approximately 30 patients ages 2 to 65.
• Patients will undergo a four‑week baseline period followed by a 12‑week treatment period where they will receive up to 600 mg of ganaxolone (oral liquid suspension) three times a day. Patients who meet eligibility criteria may continue ganaxolone treatment during a 24‑week extension to the trial.
• The primary endpoint for the trial is percent change in 28‑day primary seizure frequency for the treatment period relative to baseline. The Company plans to analyze allopregnanolone sulfate levels as part of the trial efficacy analysis.

PCDH19 Related Epilepsy (PCDH19-RE)

• Marinus remains on-track to enroll 25-30 patients (an increase from its previous guidance of 15-20 patients) in the ongoing Phase 2 Violet Study evaluating allopregnanolone sulfate as a biomarker and ganaxolone as a treatment in PCDH19-RE patients.
• The Company believes the increased patient enrollment has the potential to strengthen the ability to detect a meaningful signal as proof-of-concept for the allopregnanolone sulfate biomarker hypothesis.
• Marinus remains on-track to report topline data from this POC trial in the first half of 2021.

Webinar Details:

To listen to the live webinar at 8am ET today, please click here.

About Marinus Pharmaceuticals

Marinus Pharmaceuticals, Inc. is a pharmaceutical company dedicated to the development of innovative therapeutics to treat rare seizure disorders. Ganaxolone is a positive allosteric modulator of GABA_A receptors that acts on a well-characterized target in the brain known to have anti-seizure, anti-depressant, and anti-anxiety effects. Ganaxolone is being developed in IV and oral dose forms intended to maximize therapeutic reach to adult and pediatric patient populations in both acute and chronic care settings. Marinus is conducting the first ever Phase 3 pivotal trial in children with CDKL5 deficiency disorder, along with a Phase 2 trial in Tuberous Sclerosis Complex, and a Phase 2 biomarker driven proof of concept trial in PCDH19-related epilepsy. The Company intends to initiate a Phase 3 trial in status epilepticus. For more information visit www.marinuspharma.com.

Forward-Looking Statements

To the extent that statements contained in this press release are not descriptions of historical facts regarding Marinus, they are forward-looking statements reflecting the current beliefs and expectations of management made pursuant to the safe harbor provisions of the Private Securities Litigation Reform Act of 1995. Words such as “may”, “will”, “expect”, “anticipate”, “estimate”, “intend”, “believe”, and similar expressions (as well as other words or expressions referencing future events, conditions or circumstances) are intended to identify forward-looking statements. Examples of forward-looking statements contained in this press release include, among others, statements regarding our clinical development plans for ganaxolone; expected dosing in our clinical trials; the clinical development schedule and milestones; our expected timing to begin and complete enrollment in our clinical trials, including our expectation to dose the first patient in our Phase 3 clinical trial for SE in third quarter 2020; the expected trial design, target patient population and endpoints for our clinical trials; interpretation of scientific basis for ganaxolone use; timing for availability and release of data, including the expected release of data from the Marigold Study in the third quarter of 2020 and from the proof of concept study in PCDH19 in the first half of 2021; the potential safety and efficacy of ganaxolone; the therapeutic potential of ganaxolone; and our expectations regarding the effect of the COVID-19 pandemic on our business and clinical development plans; and our plans for an expanded access program for ganaxolone. Forward-looking statements in this press release involve substantial risks and uncertainties that could cause our clinical development programs, future results, performance or achievements to differ significantly from those expressed or implied by the forward-looking statements. Such risks and uncertainties include, among others, uncertainties and delays relating to the design, enrollment, completion, and results of clinical trials; unanticipated costs and expenses; early clinical trials may not be indicative of the results in later clinical trials; clinical trial results may not support regulatory approval or further development in a specified indication or at all; actions or advice of the U.S. Food and Drug Administration may affect the design, initiation, timing, continuation and/or progress of clinical trials or result in the need for additional clinical trials; our ability to obtain and maintain regulatory approval for our product candidate; our ability to obtain and maintain patent protection for our product candidates; delays, interruptions or failures in the manufacture and supply of our product candidate; our ability to raise additional capital; the effect of the COVID-19 pandemic on our business, the medical community and the global economy; and the availability or potential availability of alternative products or treatments for conditions targeted by us that could affect the availability or commercial potential of our product candidate. Marinus undertakes no obligation to update or revise any forward-looking statements. For a further description of the risks and uncertainties that could cause actual results to differ from those expressed in these forward-looking statements, as well as risks relating to the business of the Company in general, see filings Marinus has made with the Securities and Exchange Commission.

CONTACT:
Sasha Damouni Ellis
Vice President, Investor Relations & Corporate Communications
Marinus Pharmaceuticals, Inc.
484-253-6792
sdamouni@marinuspharma.com