# EDGAR Filing Document

**Accession Number:** 0001267813
**File Stem:** 0001558370-23-003034
**Filing Date:** 2023-3
**Character Count:** 72828
**Document Hash:** 022447bc8571dc6a333999884a184c4c
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001558370-23-003034.hdr.sgml**: 20230307

**ACCESSION NUMBER**: 0001558370-23-003034

**CONFORMED SUBMISSION TYPE**: 8-K

**PUBLIC DOCUMENT COUNT**: 56

**CONFORMED PERIOD OF REPORT**: 20230307

**ITEM INFORMATION**: Results of Operations and Financial Condition

**ITEM INFORMATION**: Other Events

**ITEM INFORMATION**: Financial Statements and Exhibits

**FILED AS OF DATE**: 20230307

**DATE AS OF CHANGE**: 20230307

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** MARINUS PHARMACEUTICALS, INC.
- **CENTRAL INDEX KEY:** 0001267813
- **STANDARD INDUSTRIAL CLASSIFICATION:** PHARMACEUTICAL PREPARATIONS [2834]
- **IRS NUMBER:** 000000000
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** 8-K
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-36576
- **FILM NUMBER:** 23712497

**BUSINESS ADDRESS:**
- **STREET 1:** 5 RADNOR CORPORATE CENTER SUITE 500
- **STREET 2:** 100 MATSONFORD RD
- **CITY:** RADNOR
- **STATE:** PA
- **ZIP:** 19087
- **BUSINESS PHONE:** 484-801-4670

**MAIL ADDRESS:**
- **STREET 1:** 5 RADNOR CORPORATE CENTER SUITE 500
- **STREET 2:** 100 MATSONFORD RD
- **CITY:** RADNOR
- **STATE:** PA
- **ZIP:** 19087

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** MARINUS PHARMACEUTICALS INC
- **DATE OF NAME CHANGE:** 20031022

?xml version='1.0' encoding='UTF-8'?

**UNITED STATES**

**SECURITIES AND EXCHANGE COMMISSION**

**Washington, D.C. 20549**

**FORM 8-K**

**CURRENT REPORT**

**PURSUANT TO SECTION 13 OR 15(d)** 

**OF THE SECURITIES EXCHANGE ACT OF 1934**

**Date of Report (Date of earliest event reported): March 7, 2023**

## Marinus Pharmaceuticals, Inc.
*(Exact name of registrant as specified in its charter)*

---

| | | |
|:---|:---|:---|
| **Delaware** | **001-36576** | **20-0198082** |
| *(State or other jurisdiction of incorporation)* | *(Commission File Number)* | *(IRS Employer Identification No.)* |

---

---

| | |
|:---|:---|
| **, Radnor, PA**<br>**5 Radnor Corporate Center, Suite 500**<br>**100 Matsonford Rd, Radnor, PA** | **19087** |
| *(Address of principal executive offices)* | *(Zip Code)* |

---

Registrant's telephone number, including area code: **(484) 801-4670**

__________________________________________________________________

*(Former name or former address, if changed since last report.)*

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐ Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐ Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

---

| | | |
|:---|:---|:---|
| Title of each class | Trading Symbol(s) | Name of each exchange on which registered |
| Common Stock, par value $0.001 | MRNS | Nasdaq Global Market  |

---

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

------

**Item 2.02. Results of Operations and Financial Condition.**

On March 7, 2023, Marinus Pharmaceuticals, Inc. (the "Company") issued a press release announcing its financial results for the quarter and year ended December 31, 2022 and certain other information. A copy of the press release is being furnished as Exhibit 99.1 to this Current Report on Form 8-K and is incorporated by reference to this Item 2.02.

The information furnished pursuant to this Item 2.02 shall not be deemed to be "filed" for purposes of Section 18 of the Securities Exchange Act of 1934 (the "Exchange Act") or otherwise subject to the liabilities of that section, nor shall it be deemed to be incorporated by reference into any of the Company's filings with the Securities and Exchange Commission under the Exchange Act or the Securities Act of 1933, whether made before or after the date hereof, regardless of any general incorporation language in such a filing, except as expressly set forth by specific reference in such a filing. Except as required by law, we undertake no duty or obligation to publicly update or revise the information so furnished.

**Item 8.01. Other Events.** 

On March 7, 2023, the Company posted the Fourth Quarter 2022 Corporate and Financial Update on its website at www.marinuspharma.com. A copy is filed as Exhibit 99.2 to this Current Report on Form 8-K and is incorporated by reference to this Item 8.01.

**Item 9.01. Financial Statements and Exhibits.**

(d)***Exhibits***

---

| | |
|:---|:---|
| **Exhibit**<br>**No.** | **Description** |
| 99.1 | [Press Release, dated March 7, 2023, of Marinus Pharmaceuticals, Inc.](mrns-20230307xex99d1.htm)  |
| 99.2 | [Corporate Presentation, Fourth Quarter 2022 Corporate and Financial Update, dated March 2023.](mrns-20230307xex99d2.htm) |
| 104 | The cover page from this Current Report on Form 8-K, formatted in Inline XBRL. |

---

#### SIGNATURES
Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

---

| | |
|:---|:---|
|  | **MARINUS PHARMACEUTICALS, INC.** |
| Date: March 7, 2023 | /s/ Steven Pfanstiel |
|  | Steven Pfanstiel |
|  | Chief Operating Officer, Chief Financial Officer and Treasurer |

---

## Exhibit 99.1

![Graphic](mrns-20230307xex99d1001.jpg)

**Exhibit 99.1**

**Marinus Pharmaceuticals Provides Business Update and Reports Fourth Quarter and Full Year 2022 Financial Results**

● ZTALMY <sup>®</sup> U.S. net product revenue of $2.3 million for the fourth quarter of 2022 and $2.9 million for the fiscal year ended December 31, 2022

● Company expects ZTALMY <sup></sup> U.S. net product revenues of between $15 million and $17 million for the fiscal year ending December 31, 2023

● Second generation oral formulation development continues to advance based on encouraging Phase 1 data

● Actively recruiting Phase 3 clinical trials in refractory status epilepticus and tuberous sclerosis complex; data continues to be expected 2H 2023 and Q1 2024, respectively

● Phase 2 clinical trial of oral ganaxolone in PCDH-19 published in *Epilepsy Research*  

● Cash and cash equivalents of $240.6 million as of December 31, 2022

● Marinus to host conference call on March 7, 2023, at 4:30 p.m. ET

**RADNOR, Pa. – March 7, 2023 –** Marinus Pharmaceuticals, Inc. (Nasdaq: MRNS), a pharmaceutical company dedicated to the development of innovative therapeutics to treat seizure disorders, today reported business highlights and financial results for the fourth quarter and year ended December 31, 2022.

"2022 was a year of significant growth and execution for Marinus, underscored by the successful U.S. launch of ZTALMY," said Scott Braunstein, M.D., Chairman and Chief Executive Officer of Marinus. "With a strong balance sheet and continued progress advancing our second generation formulation and Phase 3 trials in status epilepticus and tuberous sclerosis complex, we entered 2023 with increased confidence in our ability to expand the value proposition of ganaxolone in rare epilepsies."

**ZTALMY**<sup>®</sup>

● Continued to execute U.S. commercial launch of ZTALMY <sup>®</sup> (ganaxolone) oral suspension CV, resulting in net product revenue of $2.3 million for the fourth quarter of 2022 and $2.9 million for the fiscal year ended December 31, 2022

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;o Consistent growth in commercial patients with over 90 total completed CDKL5 deficiency disorder (CDD) prescription enrollment forms received from over 60 unique accounts for the fiscal year ended December 31, 2022

● Full year 2023 expected ZTALMY net product revenues of $15 million to $17 million

● As of February 28, 2023, total coverage for ZTALMY increased to approximately 220 million lives, including both commercial and government programs

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;o ZTALMY received favorable coverage determinations representing approximately 125 million commercial lives, or 79% of commercial plans

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;o Medicaid access in all U.S. states, Washington D.C. and Puerto Rico, representing approximately 95 million lives

**Clinical Pipeline**

<u>Status Epilepticus</u>

------

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

![Graphic](mrns-20230307xex99d1001.jpg)

● Protocol amendment for the Phase 3 RAISE trial of intravenous (IV) ganaxolone in refractory status epilepticus (RSE) has been broadly adopted and topline results continue to be expected in the second half of 2023

● Phase 3 RAISE II trial in RSE (for European registration) enrollment anticipated to begin in the second half of 2023

● Phase 2 RESET trial in established status epilepticus (ESE) site activations underway with first cohort data anticipated before year end 2023

● Successfully manufactured modified IV formulation of ganaxolone with new buffer, targeting a shelf life of at least 24 months, and expect to incorporate in RAISE trial in Q2 2023

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;o Registration batches of modified formulation to be placed on stability by Q2 2023

● Received Notice of Allowance from the U.S. Patent and Trademark Office for a second patent with claims related to the Company's clinical therapeutic regimen for the treatment of status epilepticus using IV ganaxolone

*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.*

<u>Second Generation Product Development</u>

● A Phase 1 single ascending dose study of a second generation oral formulation was conducted

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;o Preliminary Phase 1 data showed linear dose response up to 1200 mg and the potential for BID dosing with less peak / trough variability

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;o Second generation ganaxolone was generally well tolerated with no new safety signals

● Multiple ascending dose (MAD) study expected to initiate in the second quarter of 2023

● Planning to finalize clinical program design for Lennox-Gastaut syndrome in second half of 2023

● Prodrug development continues to advance with lead oral candidate selected; Phase 1 data targeted for 2024

<u>Tuberous Sclerosis Complex (TSC)</u>

● Actively screening and enrolling patients in Phase 3 TrustTSC trial of oral ganaxolone at sites in the U.S. and Europe

● Targeting approximately 90 clinical sites, including additional activations in Canada, Israel, Italy, Belgium, Australia, and China

● Topline data continues to be anticipated in the first quarter of 2024

<u>CDKL5 Deficiency Disorder (CDD) Marketing Authorization Application (MAA)</u> 

● Marinus received the Day 180 report from the European Medicines Agency (EMA) in January 2023 containing outstanding major objections, including the choice of regulatory starting material

● The Committee for Medicinal Products for Human Use (CHMP) is expected to present its opinion on the MAA in the second quarter of 2023

------

![Graphic](mrns-20230307xex99d1001.jpg)

<u>PCDH-19</u>

● Results of Phase 2 placebo-controlled clinical trial of oral ganaxolone in PCDH19-clustering epilepsy recently published in *Epilepsy Research*  

**General Business and Financial Update**

● Steven Pfanstiel promoted to Chief Operating Officer in addition to current role as Chief Financial Officer.

● Expect that cash and cash equivalents of $240.6 million as of December 31, 2022 will be sufficient to fund the Company's operating expenses, capital expenditure requirements and maintain the minimum cash balance of $15 million required under the Company's debt facility into the second half of 2024.

● In Q4 2022, Marinus completed a follow-on equity offering, a revenue interest financing agreement, and a development and commercialization agreement with Tenacia Biotechnology for the Chinese market. Combined, these three deals brought in net funding of over $100 million within the quarter.

**Financial Results (Preliminary)**

● Recognized $2.3 million and $2.9 million in net product revenues for the three and twelve months ended December 31, 2022, respectively. Net product revenue consists of ZTALMY product sales in the U.S. market, and the 4th quarter of 2022 represents the first full quarter of sales based on the Company's July 2022 launch of ZTALMY.

● Recognized $1.8 million and $6.9 million in Biomedical Advanced Research and Development Authority (BARDA) federal contract revenue for the three and twelve months ended December 31, 2022, respectively, as compared to $1.5 million and $6.4 million for the three and twelve months ended December 31, 2021, respectively.

● Recognized collaboration revenue of $3.0 million in the fourth quarter of 2022 related to the upfront payment associated with the Company's development and commercialization agreement with Tenacia.

● Research and development (R&D) expenses were $21.4 million and $79.9 million for the three and twelve months ended December 31, 2022, respectively, as compared to $18.0 million and $73.5 million, respectively, for the same periods in the prior year; the increase was due primarily to increased R&D headcount and clinical trial activity including the ongoing RSE, TSC, and ESE trials.

● Selling, general and administrative (SG&A) expenses were $14.7 million and $56.8 million for the three and twelve months ended December 31, 2022, respectively, as compared to $10.6 million and $37.3 million, respectively, for the same periods in the prior year; the primary drivers of the change were increased headcount and commercial support for the U.S. launch of ZTALMY.

● The Company had net losses of $34.3 million and $19.8 million for the three and twelve months ended December 31, 2022, respectively; cash used in operating activities increased to $112.9 million for the twelve months ended December 31, 2022, compared to $55.5 million for the same period a year ago.

● At December 31, 2022, the Company had cash and cash equivalents of $240.6 million, compared to $122.9 million at December 31, 2021.

------

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

![Graphic](mrns-20230307xex99d1001.jpg)

● Readers are referred to, and encouraged to read in its entirety, the Company's Annual Report on Form 10-K for the fiscal year ended December 31, 2022, to be filed with the Securities and Exchange Commission, which includes further details on the Company's business plans, operations, financial condition, and results of operations.

**Corporate Guidance** 

● For the fiscal year 2023, the Company expects ZTALMY U.S. net product revenues of between $15 million and $17 million, BARDA revenues in the range of $8 million to $11 million and total GAAP operating expenses, inclusive of SG&A and R&D, to be in the range of $165 to $175 million, of which the company expects stock-based compensation to be approximately $16 million.

Selected Financial Data (in thousands, except share and per share amounts)

---

| | | |
|:---|:---|:---|
|  | &nbsp;&nbsp;December 31,<br>2022<br>(Unaudited) | &nbsp;&nbsp;December 31,<br>2021 |
| &nbsp;&nbsp;ASSETS |  |  |
| &nbsp;&nbsp;Cash and cash equivalents | $&nbsp;&nbsp;240551 | $&nbsp;&nbsp;122927 |
| &nbsp;&nbsp;Other assets | &nbsp;&nbsp;18967 | &nbsp;&nbsp;13913 |
| &nbsp;&nbsp;Total assets | $&nbsp;&nbsp;259518 | $&nbsp;&nbsp;136840 |
| &nbsp;&nbsp;LIABILITIES AND STOCKHOLDERS' EQUITY |  |  |
| &nbsp;&nbsp;Current liabilities | $&nbsp;&nbsp;25017 | $&nbsp;&nbsp;40566 |
| &nbsp;&nbsp;Long term debt, net | &nbsp;&nbsp;71018 | &nbsp;&nbsp;40809 |
| &nbsp;&nbsp;Revenue interest financing payable, net of deferred<br>&nbsp;&nbsp;&nbsp;&nbsp;financing costs | &nbsp;&nbsp;<br>29857 | &nbsp;&nbsp;<br>- |
| &nbsp;&nbsp;Other long-term liabilities | &nbsp;&nbsp;17626 | &nbsp;&nbsp;1979 |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Total liabilities | &nbsp;&nbsp;143518 | &nbsp;&nbsp;83354 |
| &nbsp;&nbsp;Total stockholders' equity | &nbsp;&nbsp;116000 | &nbsp;&nbsp;53486 |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Total liabilities and stockholders' equity | $&nbsp;&nbsp;259518 | $&nbsp;&nbsp;136840 |

---

------

![Graphic](mrns-20230307xex99d1001.jpg)

---

| | | | | |
|:---|:---|:---|:---|:---|
|  | &nbsp;&nbsp;Three Months Ended December 31, | &nbsp;&nbsp;Three Months Ended December 31, | &nbsp;&nbsp;Twelve Months Ended December 31, | &nbsp;&nbsp;Twelve Months Ended December 31, |
|  | &nbsp;&nbsp;2022<br>(unaudited) | &nbsp;&nbsp;2021 | &nbsp;&nbsp;2022<br>(unaudited) | &nbsp;&nbsp;2021 |
| &nbsp;&nbsp;Revenue: |  |  |  |  |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Product revenue, net | $&nbsp;&nbsp;2317 | $&nbsp;&nbsp;- | $&nbsp;&nbsp;2872 | $&nbsp;&nbsp;- |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Federal contract revenue | &nbsp;&nbsp;1847 | &nbsp;&nbsp;1520 | &nbsp;&nbsp;6935 | &nbsp;&nbsp;6358 |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Collaboration revenue | &nbsp;&nbsp;2998 | &nbsp;&nbsp;- | &nbsp;&nbsp;15671 | &nbsp;&nbsp;8987 |
| &nbsp;&nbsp;Total revenue | &nbsp;&nbsp;7162 | &nbsp;&nbsp;1520 | &nbsp;&nbsp;25478 | &nbsp;&nbsp;15345 |
| &nbsp;&nbsp;Expenses: |  |  |  |  |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Research and development | &nbsp;&nbsp;21424 | &nbsp;&nbsp;18014 | &nbsp;&nbsp;79912 | &nbsp;&nbsp;73520 |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Selling, general and administrative | &nbsp;&nbsp;14658 | &nbsp;&nbsp;10622 | &nbsp;&nbsp;56845 | &nbsp;&nbsp;37278 |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Cost of product revenue | &nbsp;&nbsp;142 | &nbsp;&nbsp;- | &nbsp;&nbsp;190 | &nbsp;&nbsp;- |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Cost of collaboration revenue | &nbsp;&nbsp;150 | &nbsp;&nbsp;- | &nbsp;&nbsp;150 | &nbsp;&nbsp;1478 |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Cost of IP license fee | &nbsp;&nbsp;- | &nbsp;&nbsp;- | &nbsp;&nbsp;1169 | &nbsp;&nbsp;- |
| &nbsp;&nbsp;Total expenses: | &nbsp;&nbsp;36374 | &nbsp;&nbsp;28636 | &nbsp;&nbsp;138266 | &nbsp;&nbsp;112276 |
| &nbsp;&nbsp;Loss from operations | &nbsp;&nbsp;(29212) | &nbsp;&nbsp;(27116) | &nbsp;&nbsp;(112788) | &nbsp;&nbsp;(96931) |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Interest income | &nbsp;&nbsp;1744 | &nbsp;&nbsp;23 | &nbsp;&nbsp;2354 | &nbsp;&nbsp;80 |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Interest expense | &nbsp;&nbsp;(3690) | &nbsp;&nbsp;(1553) | &nbsp;&nbsp;(10672) | &nbsp;&nbsp;(2582) |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Gain from sale of priority review<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;voucher, net | &nbsp;&nbsp;<br>- | &nbsp;&nbsp;<br>- | &nbsp;&nbsp;<br>107375 | &nbsp;&nbsp;<br>- |
| &nbsp;&nbsp;Other (expense) income, net | &nbsp;&nbsp;(1517) | &nbsp;&nbsp;341 | &nbsp;&nbsp;(2696) | &nbsp;&nbsp;657 |
| &nbsp;&nbsp;Loss before income taxes | &nbsp;&nbsp;(32675) | &nbsp;&nbsp;(28305) | &nbsp;&nbsp;(16427) | &nbsp;&nbsp;(98776) |
| &nbsp;&nbsp;Provision for income taxes | &nbsp;&nbsp;(1637) | &nbsp;&nbsp;- | &nbsp;&nbsp;(3389) | &nbsp;&nbsp;- |
| &nbsp;&nbsp;Net loss and comprehensive loss | $&nbsp;&nbsp;(34312) | $&nbsp;&nbsp;(28305) | $&nbsp;&nbsp;(19816) | $&nbsp;&nbsp;(98776) |
| &nbsp;&nbsp;Per share information: |  |  |  |  |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Net loss per share of common stock –<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;basic and diluted | $&nbsp;&nbsp;(0.76) | $&nbsp;&nbsp;(0.77) | $&nbsp;&nbsp;(0.51) | $&nbsp;&nbsp;(2.69) |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Basic and diluted weighted average<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;shares outstanding | &nbsp;&nbsp;<br>44973371 | &nbsp;&nbsp;<br>36746112 | &nbsp;&nbsp;<br>39072599 | &nbsp;&nbsp;<br>36697171 |

---

**Conference Call Information**

Participants may access the conference call via webcast on the Investor page of Marinus' website at ir.marinuspharma.com/events-and-presentations. An archived version of the call will be available approximately two hours after the completion of the event on the website.

**About Marinus Pharmaceuticals**

Marinus is a commercial-stage pharmaceutical company dedicated to the development of innovative therapeutics for seizure disorders. The Company's commercial product, ZTALMY<sup>®</sup> (ganaxolone) oral suspension CV, has been approved by the U.S. FDA for the treatment of seizures associated with CDKL5 deficiency disorder in patients two years of age and older. The potential of ganaxolone is also being studied in other seizure disorders, including in Phase 3 trials in tuberous sclerosis complex and refractory status epilepticus. Ganaxolone is a neuroactive steroid GABA<sub>A</sub> receptor modulator that acts on a well-characterized target in the brain known to have anti-seizure effects. It is being developed in IV and oral formulations to maximize therapeutic reach for adult and pediatric patients in acute and chronic care settings. For more information visit www.marinuspharma.com<u>.</u>

**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",

------

![Graphic](mrns-20230307xex99d1001.jpg)

"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 commercialization and marketing plans for ZTALMY; the potential benefits ZTALMY will provide for physicians and patients; our expectations regarding the ZTALMY One program; statements regarding our expected clinical development plans, enrollment in our clinical trials, regulatory communications and submissions for ganaxolone, and the timing thereof; our expected cash runway; our expectations regarding BARDA funding; our expectations and beliefs regarding the FDA and EMA with respect to our product candidates; our expectations regarding the development of new formulations and prodrug candidates; our expectation regarding the impact of the COVID-19 pandemic on our business and clinical development plans; our financial projections; the potential safety and efficacy of ganaxolone, as well as its therapeutic potential in a number of indications; and other statements regarding the company's future operations, financial performance, financial position, prospects, objectives and other future event.

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, unexpected results or delays in the commercialization of ZTALMY; unexpected market acceptance, payor coverage or future prescriptions and revenue generated by ZTALMY; unexpected actions by the FDA or other regulatory agencies with respect to our products; competitive conditions and unexpected adverse events or patient outcomes from being treated with ZTALMY, uncertainties and delays relating to the design, enrollment, completion, and results of clinical trials; unanticipated costs and expenses; the varying interpretation of clinical data; our ability to comply with the FDA's requirement for additional post-marketing studies in the required time frames; the timing of regulatory filings for our other product candidates; the potential that regulatory authorities, including the FDA and EMA, may not grant or may delay approval for our product candidates including with respect to the CDD MAA; 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 FDA or EMA 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 develop new formulations of ganaxolone or prodrugs; our ability to obtain, maintain, protect and defend intellectual property for our product candidates; the potential negative impact of third party patents on our or our collaborators' ability to commercialize ganaxolone; delays, interruptions or failures in the manufacture and supply of our product candidate; the size and growth potential of the markets for the company's product candidates, and the company's ability to service those markets; the company's cash and cash equivalents may not be sufficient to support its operating plan for as long as anticipated; the company's expectations, projections and estimates regarding expenses, future revenue, capital requirements, and the availability of and the need for additional financing; the company's ability to obtain additional funding to support its clinical development and commercial programs; the potential for our ex-US partners to breach their obligations under their respective agreements with us or terminate such agreements in accordance with their respective terms; the risk that drug product quality requirements may not support continued clinical investigation of our product candidates and result in delays or termination of such clinical studies and product approvals; the effect of the COVID-19 pandemic on our business, the medical community, regulators 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

------

![Graphic](mrns-20230307xex99d1001.jpg)

product candidate. This list is not exhaustive and these and other risks are described in our periodic reports, including the annual report on Form 10-K, quarterly reports on Form 10-Q and current reports on Form 8-K, filed with or furnished to the Securities and Exchange Commission and available at www.sec.gov. Any forward-looking statements that we make in this press release speak only as of the date of this press release. We assume no obligation to update forward-looking statements whether as a result of new information, future events or otherwise, after the date of this press release.

**Company Contact**<br>Sasha Damouni Ellis<br>Senior Vice President, Corporate Affairs & Investor Relations<br>Marinus Pharmaceuticals, Inc.<br>sdamouni@marinuspharma.com

------

## Exhibit 99.2

#### Exhibit 99.2

---

| | |
|:---|:---|
| &nbsp;&nbsp;![GRAPHIC](mrns-20230307xex99d2g001.jpg) | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Nasdaq: MRNS @MarinusPharma Photo Credit: Kelly Crews Photography Ryan (center) Living with CDKL5 deficiency disorder Corporate Presentation March 2023 |

---

---

| | |
|:---|:---|
| &nbsp;&nbsp;![GRAPHIC](mrns-20230307xex99d2g002.jpg) | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;©2023 Marinus Pharmaceuticals. All Rights Reserved I To the extent that statements contained in this presentation 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 presentation include, among others, statements regarding our expected revenue and operating expenses for 2023; our commercialization plans for ZTALMY® and clinical development plans for ganaxolone and the expected timing thereof; our anticipated and potential financing plans; expected dosing in our clinical trials; the clinical development schedule and milestones; our expected timing to begin and complete enrollment in our clinical trials; 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; the potential safety and efficacy and therapeutic potential of ganaxolone; timing and expectations regarding the potential benefits ZTALMY will provide for patients and physicians, our expectations regarding the ZTALMY One program; timing and expectations regarding regulatory communications and submissions; expectations regarding our agreement with BARDA; expectations regarding our collaborations with ex-US partners; expectations regarding the potential market opportunities for our product candidates, including oral ganaxolone; potential commercial alliances; expectations regarding our cash flow and cash runway; and our expectations regarding the effect of the COVID-19 pandemic on our business and clinical development plans. Forward-looking statements in this presentation 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 our ability to establish commercial infrastructure and capabilities to deliver commercial supply of ZTALMY, patient and physician acceptance of ZTALMY, our ability to obtain adequate market access for ZTALMY; our ability to comply with the FDA's requirement for additional post-market studies in the required timeframes; the timing of regulatory filings, including the timing of filing the ganaxolone MAA with the EMA; the potential that regulatory authorities, including the FDA and EMA, may not grant or may delay approval for our product candidates; 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 FDA or EMA 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 candidates; our ability to obtain, maintain, protect and defend intellectual property for our product candidates; the potential negative impact of third party patents on our or our collaborators' ability to commercialize ganaxolone; delays, interruptions or failures in the manufacture and supply of our product candidates; the size and growth potential of the markets for our product candidates, and our ability to service those markets; our cash and cash equivalents may not be sufficient to support our operating plan for as long as anticipated; our expectations, projections and estimates regarding expenses, future revenue, capital requirements, and the availability of and the need for additional financing; our ability to obtain additional funding to support our commercial and clinical development programs; the potential for our ex-US partners to breach our collaboration agreement or terminate the agreement in accordance with its terms; the effect of the COVID-19 pandemic on our business, the medical community, regulators 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 candidates. 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 our business in general, see filings we have made with the Securities and Exchange Commission. You may access these documents for free by visiting EDGAR on the SEC web site at www.sec.gov. Safe Harbor Statement 2 |

---

---

| | |
|:---|:---|
| &nbsp;&nbsp;![GRAPHIC](mrns-20230307xex99d2g003.jpg) | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;©2023 Marinus Pharmaceuticals. All Rights Reserved I Ganaxolone Development Pipeline 3 PDUFA date March 2022 MAA filing validation Q4 2021 Ph3 patient enrollment Q1 2022 Topline data 1H 2024 GANAXOLONE Phase 1 Phase 2 Phase 3 Approved Oral Suspension Intravenous Intravenous Intravenous Oral Suspension (Second Gen. Formulation) Administered Seizure Disorders Oral Suspension CDKL5 Deficiency Disorder Marigold Study FDA approved Topline data 2H 2023 Enroll first patient 2H 2023 First cohort data year end 2023 Initiate multiple ascending dose trial Q2 2023 Topline data Q1 2024 Ongoing trial Planned future trial Preclinical Lennox-Gastaut Syndrome Anticipated Milestones EU CHMP opinion Q2 2023 Refractory Status Epilepticus RAISE Trial Tuberous Sclerosis Complex TrustTSC Trial Established Status Epilepticus RESET Trial Second Generation Formulation Refractory Status Epilepticus RAISE II Trial Ganaxolone is a positive allosteric GABAA receptor modulator with a well-defined MOA designed to treat patients suffering from seizure disorders. Ganaxolone is designed to modulate both synaptic and extrasynaptic GABAA receptors to calm over-excited neurons. |

---

---

| | |
|:---|:---|
| &nbsp;&nbsp;![GRAPHIC](mrns-20230307xex99d2g004.jpg) | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;©2023 Marinus Pharmaceuticals. All Rights Reserved I 4 ¹Symonds JD 2019 Brain ²Curatolo P, Bombardieri R, Jozwiak S. Tuberous sclerosis. Lancet. 2008;372:657–68. ³DeLorenzo RJ et al. J Clin Neurophysiol. 1995; 12: 316-325 4Kapur et al. N Engl J Med 2019;381:2103-13 5Rossetti and Lowenstein. Lancet Neurol. 2011 Oct; 10(10): 922–930 6Trevathan et al. (1997). Epilepsia, 38(12), 1283–1288 Ganaxolone U.S. Market Opportunity Oral Ganaxolone Intravenous (IV) Ganaxolone Second Generation Product Development Stage Incidence / Prevalence Seizure type(s) Indication CDKL5 deficiency disorder Tuberous sclerosis complex FDA approved for seizures associated with CDD in patients 2 and older - Ph3 TrustTSC trial underway - Topline data anticipated Q1 2024 - 1:40,000 live births¹ - 90-100 U.S. newborns / year - 1:6,000 live births2 - 25-40k refractory U.S. patients Generalized and focal seizures Focal seizures (primarily) Refractory status epilepticus Established status epilepticus - Ph3 RAISE trial underway - Topline data anticipated 2H 2023 - Ph3 RAISE II trial for European registration expected to initiate 2H 2023 - First cohort data anticipated year end 2023 35k U.S. patients / year3,5 75k patients / year 3,4 Continuous/persistent electrographic or clinical seizures Lennox-Gastaut syndrome - Initiate multiple ascending dose trial Q2 2023 - 26:100,000 people6 - 48k U.S. patients - Drop seizures (atonic, tonic, or tonic-clonic) - 90% intractable COMMERCIAL PIPELINE PIPELINE PIPELINE Not for promotional use |

---

---

| | |
|:---|:---|
| &nbsp;&nbsp;![GRAPHIC](mrns-20230307xex99d2g005.jpg) | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;ZTALMY® (ganaxolone) oral suspension CV Marigold Clinical Data & Commercial Launch Not for promotional use |

---

---

| | |
|:---|:---|
| &nbsp;&nbsp;![GRAPHIC](mrns-20230307xex99d2g006.jpg) | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;©2023 Marinus Pharmaceuticals. All Rights Reserved I 6 Ganaxolone Placebo 0 10 20 30 40 Median Percent Reduction 28-day Frequency of Major Motor Seizures 30.7% 6.9% \*Wilcoxon Rank-Sum Test \*\*Hodges-Lehman Estimate of Median Dif erence Patients taking ganaxolone experienced a significant reduction in seizure frequency Ganaxolone reduced the frequency of monthly major motor seizures by a median of 30.7% compared with 6.9% for placebo (p=0.0036)\* Δ = 27.1% (47.9 - 9.6)\*\* \*Hodges-Lehmann estimate of median difference (95% confidence interval); \*\*Wilcoxon rank-sum test Data as of July 22, 2021 1. Pestana-Knight EM, et al. Lancet Neurol. 2022;21(5):417-427. 2. Data on file. Reduction in monthly major motor seizure frequency over 24 months in OLE ► At the time of the analysis, 54 patients (61.4%) were still in the OLE study ► Median percent reductions in MMSF from baseline ranged 25% to 42% during initial 12 months and was between 44% and 56% through 24 months in the OLE phase • Open-label design and small sample size preclude efficacy conclusions from being drawn ► No new safety findings emerged in the OLE preliminary analysis and adverse reactions were consistent with the double-blind phase1 Seizure reductions were observed in OLE patients Phase 3 Marigold data published in The Lancet Neurology First international CDKL5 guidelines published in Frontiers in Neurology Phase 3 Marigold Trial and Open Label Extension Data Not for promotional use |

---

---

| | |
|:---|:---|
| &nbsp;&nbsp;![GRAPHIC](mrns-20230307xex99d2g007.jpg) | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;©2023 Marinus Pharmaceuticals. All Rights Reserved I ZTALMY® Performance Metrics Indicate Early Launch Success 7 • $2.3M ZTALMY® U.S. net product revenues • ~40 completed CDD prescription enrollment forms received from 30+ unique accounts • ~90 completed CDD prescription enrollment forms received from 60+ unique accounts • >75% of CDD patients with completed prescription enrollment forms were able to receive reimbursed therapy, with an average conversion rate of ~30 days • ~5 average bottles per naive patient with median age of ~10 years old • As of February 28, 2023, total coverage for ZTALMY increased to ~220M lives, including both commercial and government programs • Received favorable coverage determinations representing ~125M commercial lives or 79% of commercial plans; Medicaid access in all U.S. states, Washington D.C. and Puerto Rico, representing ~95M lives • Expect ZTALMY U.S. net product revenues of between $15M -$17M for the fiscal year 2023 Q4 2022: Fiscal Year 2022: 2023 Update: Not for promotional use |

---

---

| | |
|:---|:---|
| &nbsp;&nbsp;![GRAPHIC](mrns-20230307xex99d2g008.jpg) | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;©2023 Marinus Pharmaceuticals. All Rights Reserved I ZTALMY U.S. Market Opportunity & Key Accounts 8 ~2,000 Addressable Pediatric Patients\* Several data points suggest additional market opportunity in adult population 1Symonds JD 2019 Brain \*Estimated based on Symonds JD 2019 Brain • 8 CDD Centers of Excellence & 40 National Association of Epilepsy Centers • Genetic testing/screening widely used and available for early diagnoses • Usage of ICD-10 code continues to increase • Insights from key advocacy groups Refractory to current treatments Target patient population: ages 2-21 with seizures 1 in 40,000 live births have CDKL5 Deficiency Disorder1 Factors that support addressable patient population: CDD 'A' Accounts (40) • National Association of Epilepsy Centers • Largest # of patient claims • Early adopters • High influence CDD 'B' Accounts (47) • Large # of patient claims • Delayed adoption • High influence CDD 'C' Accounts (178) • Medium # of patient claims • Adoption of new therapies • Require targeted commercial effort CDD Centers of Excellence (8) • Included for in A & B accounts • Sponsored by International Foundation for CDKL5 • Coordinated multi-specialty effort to address entirety of burden of disease Sales Lead, 2 Area Directors, 16 Field Representatives Market Access Team, 2 Area Directors, 1 Director Government Access, Channel Strategy & Operations Targeted & Scalable Commercial Structure Not for promotional use |

---

---

| | |
|:---|:---|
| &nbsp;&nbsp;![GRAPHIC](mrns-20230307xex99d2g009.jpg) | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Rare Epilepsies Oral Ganaxolone Pipeline |

---

---

| | |
|:---|:---|
| &nbsp;&nbsp;![GRAPHIC](mrns-20230307xex99d2g010.jpg) | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Tuberous Sclerosis Complex "Many individuals with TSC continue to experience uncontrolled seizures despite a cocktail of multiple antiepileptic drugs. Because new options are always needed, the TSC community welcomes clinical evaluation of new epilepsy treatments" - Kari Luther Rosbeck, President & CEO of the Tuberous Sclerosis Alliance  |

---

---

| | |
|:---|:---|
| &nbsp;&nbsp;![GRAPHIC](mrns-20230307xex99d2g011.jpg) | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;©2023 Marinus Pharmaceuticals. All Rights Reserved I 11 Tuberous Sclerosis Complex (TSC) 1 diMichele, et al, J. Neuro Neurosurg Psychiatry, 2003 \*Failure of two prior antiseizure medications with ongoing, frequent seizures. CAUSE • Defect or mutation of TSC1 and/or TSC2 genes SYMPTOMS • Benign tumors, seizures, cognitive impairment, behavioral difficulties, skin abnormalities INCIDENCE PREVALENCE • 1:6,000 live births • ~25K-40K refractory TSC patients in the U.S.\* TREATMENTS • Despite available treatments, continued unmet medical need MECHANISTIC RATIONALE • Potential neurosteroid deficiency1 • Pathophysiology may involve GABAergic dysfunction |

---

---

| | |
|:---|:---|
| &nbsp;&nbsp;![GRAPHIC](mrns-20230307xex99d2g012.jpg) | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;©2023 Marinus Pharmaceuticals. All Rights Reserved I TSC Phase 2 Trial Results 12 \* -200 -100 -80 -60 -40 -20 0 20 40 60 80 100 Percent reduction in TSC-associated seizure frequency =median 16.6% Secondary and Exploratory Analyses Primary Endpoint Results: 16.6% median reduction in TSC-associated seizures Ganaxolone was generally well-tolerated with somnolence, sedation and fatigue reported as the most common adverse events; in addition, one treatment-related serious adverse event of seizure was reported in the trial \* Secondary endpoint Proportion of patients with a ≥50% reduction in TSC-associated seizure frequency Intent to Treat (n=23) +Cannabidiol (n=12) +Everolimus (n=11) 0 5 10 15 20 25 30 35 40 45 50 36.4 25.0 30.4 Percent of patients % % % Subjects with Focal Seizure Types (n=19) 0 10 20 30 25.2 Percent reduction in focal seizure frequency (median) % |

---

---

| | |
|:---|:---|
| &nbsp;&nbsp;![GRAPHIC](mrns-20230307xex99d2g013.jpg) | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;©2023 Marinus Pharmaceuticals. All Rights Reserved I Phase 3 Protocol Refinements Informed by Phase 2 13 Phase 3 Slower titration initially, designed to optimize tolerability and improve efficacy 0 7 14 21 28 35 0 20 40 60 80 100 Time (days) Approx. % Max GNX Dose TSC Ph2 Titration TSC Ph3 Titration No (n=6) Yes (n=17) 0 5 10 15 20 25 30 Somnolence-related AE Percentreduction in TSC-associated seizure frequency (median) Phase 2 Patients without somnolence related AEs experienced directionally better seizure reductions |

---

---

| | |
|:---|:---|
| &nbsp;&nbsp;![GRAPHIC](mrns-20230307xex99d2g014.jpg) | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;©2023 Marinus Pharmaceuticals. All Rights Reserved I Phase 3 Trial Overview 14 ► Enrollment: ~162 patients, targeting 85 sites in the U.S., Western Europe, Canada, Israel and Australia ► Primary Endpoint: Percent change in 28-day TSC-associated seizure frequency ► Key Secondary Endpoints: Percent change in TSC-associated seizure frequency during 12-week maintenance period, 50% responder rate, and clinical global impression ► FDA has indicated a single pivotal TSC Phase 3 trial could be sufficient for approval Ganaxolone Placebo Baseline (4 weeks) Titration (28 days) Maintenance (12 weeks) Eligible Patients with TSC R 1:1 Primary Endpoint Analysis Open-label Ganaxolone Double-blind Phase |

---

---

| | |
|:---|:---|
| &nbsp;&nbsp;![GRAPHIC](mrns-20230307xex99d2g015.jpg) | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Second Generation Product Development |

---

---

| | |
|:---|:---|
| &nbsp;&nbsp;![GRAPHIC](mrns-20230307xex99d2g016.jpg) | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;©2023 Marinus Pharmaceuticals. All Rights Reserved I Second Generation Ganaxolone 16 Goals Target Oral Pharmacokinetic Profile Increase efficacy Consistent delivery to achieve target plasma concentration Improve tolerability Optimize PK profile to reduce Cmax-related adverse effects Reduce dosing frequency More sustained exposure to allow once- or twice-daily dosing Lower cost of goods Better absorption to reduce API requirements per dose Enhance IP protection Improve formulation characteristics to provide opportunity for new IP AUC Cmax Tmax MEC MTC Current profile Target profile Increase the proportion of time the plasma level exceeds a minimally effective concentration (MEC) Avoid a significant increase in peak level (Cmax) that would exceed the maximum tolerated concentration (MTC) Second-generation ganaxolone development approaches: • Reformulation • Prodrug |

---

---

| | |
|:---|:---|
| &nbsp;&nbsp;![GRAPHIC](mrns-20230307xex99d2g017.jpg) | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;©2023 Marinus Pharmaceuticals. All Rights Reserved I Phase 1 Oral Reformulation Single Ascending Dose (SAD) PK Ganaxolone reformulation demonstrates linear kinetics at single doses from 100-1200 mg 0 500 1000 1500 2000 2500 3000 3500 100 200 300 400 500 600 700 800 900 1000 1100 1200 Mean AUC0-t (ng\*hr/mL) Dose (mg) AUC Reference Reformulation MAD historical reference 0.0 50.0 100.0 150.0 200.0 250.0 300.0 350.0 100 200 300 400 500 600 700 800 900 1000 1100 1200 Mean Cmax (ng/mL) Dose (mg) Cmax Reference Reformulation MAD historical reference Trial Design Single dose PK trial in healthy adult volunteers Evaluated PK profile of 100, 200, 400, 600, 900 and 1200 mg of reformulated oral ganaxolone Compared to reference formulation (ganaxolone suspension) at doses of 400, 600 and 900 mg Ganaxolone reformulation administered as sprinkle mixed with water or yogurt 17 |

---

---

| | |
|:---|:---|
| &nbsp;&nbsp;![GRAPHIC](mrns-20230307xex99d2g018.jpg) | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;©2023 Marinus Pharmaceuticals. All Rights Reserved I 18 Modeling of multiple dose BID PK from SAD data Cmax ~ 187 ng/mL Cmin~ 50 ng/mL Steady state PK modeling shows linear dose exposure relationship up to 1500 mg BID for ganaxolone reformulation 0.0 50.0 100.0 150.0 200.0 250.0 300.0 350.0 400.0 450.0 100 200 300 400 500 600 700 800 900 1000 1100 1200 Mean Cmax (ng/mL) Dose (mg)\* Cmax Reformulation multiple dose PK model MAD data oral suspension Measured ganaxolone concentration, 900 mg single dose Modeling of BID PK from SAD study, 900 mg BID Oral suspension: 900 mg BID Reformulation: 900 mg BID Cmax ~ 251 ng/mL Cmin~ 92 ng/mL Oral Ganaxolone Steady state Reformulation: Potential for Optimized Efficacy, Tolerability and Dosing Frequency |

---

---

| | |
|:---|:---|
| &nbsp;&nbsp;![GRAPHIC](mrns-20230307xex99d2g019.jpg) | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;©2023 Marinus Pharmaceuticals. All Rights Reserved I Next Steps: Ganaxolone Reformulation and Prodrug 19 Ganaxolone Prodrug Cohort Dose (BID) N Vehicle Diet 1 600 6 A A 2a 900 6 B B 2b 900 6 B A 2c 900 6 C A 3a 1200 6 B B 3b 1200 6 B A MAD Trial design • Healthy adult volunteers • 36 subjects in 6 equal cohorts • All cohorts receive BID GNX reformulation • Steady state PK assessment on Day 8 • Incorporates assessment of food effect and vehicle Oral prodrug candidate selected Goals: • Optimize PK parameters for efficacy, tolerability and dosing frequency • Increase absorption (oral), solubility (IV) Preclinical: IND-enabling trials to initiate Q3 2023 Clinical: Phase 1 trials to initiate Q3 2024 MAD trial starting Q2 2023 Planning to finalize clinical program design for Lennox-Gastaut syndrome in second half of 2023 |

---

---

| | |
|:---|:---|
| &nbsp;&nbsp;![GRAPHIC](mrns-20230307xex99d2g020.jpg) | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;©2023 Marinus Pharmaceuticals. All Rights Reserved I Development plan goals • Efficiently select next generation product for clinical development in LGS and other potential indications • Proceed with targeted investments in parallel formulation and prodrug development to accelerate entry to Phase 2/3 • Ensure data related to PK, PD and CMC is sufficient to inform decisions to enter and advance clinical development Pathways to a Novel Oral Formulation for Lennox-Gastaut Syndrome Phase 2A LGS Key Decision Point: Selection of optimal LGS development candidate: prodrug or next generation ganaxolone formulation Reformulation Candidates Final decision for Phase 2b & 3 will be driven by pharmacokinetics, safety / tolerability, dosing schedule, IP and COGS Preclinical PK Candidate 1 Preclinical PK Candidate 2 Prodrug Candidates >150 synthesized Screening IND enabling studies Preclinical PK SAD MAD Phase 3 LGS SAD Phase 2B LGS = Decision point SAD: single-ascending dose MAD: multiple-ascending dose Reformulation Prodrug 20 MAD |

---

---

| | |
|:---|:---|
| &nbsp;&nbsp;![GRAPHIC](mrns-20230307xex99d2g021.jpg) | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Acute Seizure Disorders Intravenous (IV) Ganaxolone Pipeline |

---

---

| | |
|:---|:---|
| &nbsp;&nbsp;![GRAPHIC](mrns-20230307xex99d2g022.jpg) | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Status Epilepticus |

---

---

| | |
|:---|:---|
| &nbsp;&nbsp;![GRAPHIC](mrns-20230307xex99d2g023.jpg) | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;©2023 Marinus Pharmaceuticals. All Rights Reserved I Status Epilepticus (SE): Definition and Epidemiology 23 SE is the second most common neurologic emergency in the U.S.1 150,000 cases per year2 1. Anesthesia and Intensive Care Medicine, February 02, 2018 , Update on the management of status epilepticus 2. DeLorenzo RJ Pellock JM Towne AR Boggs JG. Epidemiology of status epilepticus. J Clin Neurophysiol. 1995; 12: 316-325 Background Prolonged continuous or near-continuous seizures Heterogeneous patient population with etiologies that include brain tumors, stroke, encephalitis, drug intoxication, or alcohol withdrawal Pre-existing epilepsy in less than half of SE cases Status epilepticus can result in permanent neuronal damage and contribute to high morbidity and mortality Becomes more treatment refractory with progression |

---

---

| | |
|:---|:---|
| &nbsp;&nbsp;![GRAPHIC](mrns-20230307xex99d2g024.jpg) | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;©2023 Marinus Pharmaceuticals. All Rights Reserved I 24 Pharmacokinetics/Pharmacodynamics Well Suited for Acute SE Treatment Experimental PK – plasma and brain1 Brain and plasma concentration after ganaxolone 3 mg/kg IM in mice Human PD – EEG changes2 EEG bispectral index in healthy volunteers following IV ganaxolone 1. Zolkowska D, Wu CY, Rogawski MA. Intramuscular allopregnanolone and ganaxolone in a mouse model of treatment-resistant status epilepticus. Epilepsia. 2018 Oct;59:220-7. 2. Data on file, Marinus Pharmaceuticals, inc. Human PK2 Following 30 mg ganaxolone bolus (over 5 minutes): Cmax 1,240 ng/mL Tmax 0.08 hrs Ganaxolone activates the extrasynaptic GABAA receptor, is associated with high brain concentrations, and delivers a rapid onset of action.  |

---

---

| | |
|:---|:---|
| &nbsp;&nbsp;![GRAPHIC](mrns-20230307xex99d2g025.jpg) | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;©2023 Marinus Pharmaceuticals. All Rights Reserved I Strategic Approach to SE Clinical Development 25 1. DeLorenzo RJ Pellock JM Towne AR Boggs JG. Epidemiology of status epilepticus. J Clin Neurophysiol. 1995; 12: 316-325 2. Kapur et al. Randomized Trial of Three Anticonvulsant Medications for Status Epilepticus N Engl J Med 2019;381:2103-13. 3. Rossetti and Lowenstein. Management of refractory status epilepticus in adults Lancet Neurol. 2011 Oct; 10(10): 922–930 Benzodiazepine Administered (Medically induced Coma) Established Status Epilepticus (ESE) IV AEDs (antiepileptic drugs) IV Anesthetics Super Refractory Status Epilepticus (SRSE) Refractory Status Epilepticus (RSE) 1st Line Status Epilepticus 2nd Line 3rd Line 150,000 Pts/Year1 75,000 Pts/Year2 35,000 Pts/Year3 10,000 Pts/Year3 |

---

---

| | |
|:---|:---|
| &nbsp;&nbsp;![GRAPHIC](mrns-20230307xex99d2g026.jpg) | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;©2023 Marinus Pharmaceuticals. All Rights Reserved I Treatment Period Loading Dose Maintenance Taper 26 Phase 2 Refractory Status Epilepticus Trial (RSE) Design • Diagnosis of convulsive or non-convulsive SE • Failed at least one 2nd line IV AED but had not progressed to 3rd line IV anesthetics Bolus plus continuous infusion 2-4 day infusion 18-hour taper Screening Post-treatment Follow-up 24 hour Weeks 2, 3, 4 SE Patients Cohort Dose of ganaxolone/day N Low 500mg/day 5 Medium 650mg/day 4 High 713mg/day 8 Goals of a new treatment Limitations of current treatments Endpoints • Rapid cessation • Maintenance of seizure control • Prevent progression to IV anesthetics • 1st line Benzodiazepines ineffective in 45%-50%; limited by cardiovascular and respiratory side effects • 2nd line Ineffective in over 50% of established SE; further decreased response in refractory SE • 3rd line IV Anesthetics: high morbidity, mortality ~35%; increased duration of hospitalization and costs of care • Primary: Percent of patients who did not require escalation of treatment with IV anesthetic within the first 24 hours after ganaxolone initiation • Secondary: Additional efficacy, safety and tolerability 8 males, 9 females Mean age: 57 years old (range: 23-88) 17 patients enrolled |

---

---

| | |
|:---|:---|
| &nbsp;&nbsp;![GRAPHIC](mrns-20230307xex99d2g027.jpg) | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;©2023 Marinus Pharmaceuticals. All Rights Reserved I 27 Phase 2 Trial Results Demonstrated Rapid Onset And Durability of Effect Data presented at AES 2019 AEDs – antiepileptic drugs Cohort No escalation to IV anesthetics within 24 hours from infusion initiation (Primary Endpoint) Status-free through 24 hours from infusion initiation (investigator determination) No escalation to additional IV AEDs or IV anesthetics for status relapse at any time through 24 hours after ganaxolone discontinuation No SE Relapse at anytime during the 4-wk follow up period High (713 mg/day) (n=8) 100% (8 of 8) 88% (7 of 8) 100% (8 of 8) 100% (6 of 6) (1ET, 1 died) Medium (650 mg/day) (n=4) 100% (4 of 4) 100% (4 of 4) 75% (3 of 4) 67% (2 of 3) (1 ET) Low (500 mg/day) (n=5) 100% (5 of 5) 100% (5 of 5) 60% (3 of 5) 50% (1 of 2) (1 died) Immediate Prior AED Administered 4 Hours (mean) to ganaxolone treatment SE Cessation Occurred Rapidly in All Dose Groups (median = 5 minutes) Safety Summary: • 2 treatment emergent serious adverse events noted as severe sedation • 13 treatment emergent adverse events: 5 moderate (4 somnolence; 1 hypercarbia); 6 mild (2 hypotension, 2 somnolence, 1 urinary retention, 1 hypercarbia) Trial data published in Epilepsia |

---

---

| | |
|:---|:---|
| &nbsp;&nbsp;![GRAPHIC](mrns-20230307xex99d2g028.jpg) | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;©2023 Marinus Pharmaceuticals. All Rights Reserved I 28 PK/PD Relationship and Rationale for Target Dose Modeled PK Curves for All Dose Groups High Dose Achieved Target Range ≥ 500 ng/mL for ~8 hours Only High Dose Provided Sustained Reduction (>80%) Throughout Entire Analysis Window Data presented at AES 2019 PK: Pharmacokinetics / PD: Pharmadynamic Seizure Burden Reduction Occurred Rapidly in All Dose Groups |

---

---

| | |
|:---|:---|
| &nbsp;&nbsp;![GRAPHIC](mrns-20230307xex99d2g029.jpg) | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;©2023 Marinus Pharmaceuticals. All Rights Reserved I RAISE: Phase 3 Trial in Refractory Status Epilepticus 29 Ganaxolone development for RSE is being funded, in part, by the Biomedical Advanced Research and Development Authority (BARDA), part of the Office of the Assistant Secretary for Preparedness and Response at the U.S. Department of Health and Human Services, under contract number 75A50120C00159. TRIAL DESIGN • Double-blind, randomized, placebo-controlled trial in 124 patients with RSE DOSING • 36-hour infusion followed by a 12-hour taper (48-hour treatment) • Phase 2 dose paradigm and extends ganaxolone plasma exposure ≥ 500 ng/mL for 12 hours CO-PRIMARY ENDPOINTS • Proportion of participants with SE cessation within 30 minutes of trial drug initiation without medications for acute treatment of SE • Proportion of participants with no progression to IV anesthesia for 36 hours following trial drug initiation SECONDARY ENDPOINTS • No progression to IV anesthesia for 24 hours off trial drug (72 hours) • Time to SE cessation • Healthcare utilization metrics (e.g., length of stay, # of ICU days • Functional outcomes ANALYSIS • Sequential testing of primary followed by key secondary endpoints • Analysis plan allows for potential interim analysis at N=82 subjects SCREENING Dose Initiation (Time 0) Treatment Period Follow-up Period Weeks 1,2,3 & 4 Daily 48-120 hours Day 2 Hours 24-48 Hours 36-48 (taper) Daily Hours 0 -24 Bolus dose Continuous Infusion Taper Treatment duration is 2 days (including a 12-hour taper) |

---

---

| | |
|:---|:---|
| &nbsp;&nbsp;![GRAPHIC](mrns-20230307xex99d2g030.jpg) | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;©2023 Marinus Pharmaceuticals. All Rights Reserved I Patient Demographics: RSE Phase 2 vs. Phase 3 30 \*This is preliminary data is as of the end of Q3 2022 and may not be representative of demographics of patients upon full enrollment of the RAISE trial Age (mean range) Consented Subjects Dosed History of Epilepsy Seizure Burden (Standard Deviation) 56.9 (23-88) 55.6 (15-88) 53% 58% 81% 57% 61.4% (37) 44.6% (36) STESS (SE Severity Score - mean range) Etiology With Prominent Motor features 2.8 (0-6) 2.8 (0-6) 29% 22% Tumors Stroke/hemorrhage Traumatic brain injury Neurodegenerative disorder Alcohol withdrawal Illicit drug use Metabolic disturbance Infection Autoimmune disorder Tumors Stroke/hemorrhage Traumatic brain injury Alcohol withdrawal Infection Autoimmune disorder Medication noncompliance Tuberous sclerosis Open Label Phase 2 RSE Trial Phase 3 RSE Trial\*  |

---

---

| | |
|:---|:---|
| &nbsp;&nbsp;![GRAPHIC](mrns-20230307xex99d2g031.jpg) | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;©2023 Marinus Pharmaceuticals. All Rights Reserved I RESET: Phase 2 Trial in Established Status Epilepticus 31 1 Kapur et al. Randomized Trial of Three Anticonvulsant Medications for Status Epilepticus N Engl J Med 2019;381:2103-13. Key Trial points: • Patients with convulsive status epilepticus • New dosing paradigm • FDA has indicated alignment on overall study design • Exception From Informed Consent community engagement planning underway • Planned start in 2H 2022 Benzodiazepine Administered IV AEDs (antiepileptic drugs) IV Anesthetics (Medically Established Status induced Coma) Epilepticus (ESE) Super Refractory Status Epilepticus (SRSE) Refractory Status Epilepticus (RSE) 1st Line 2nd Line 3rd Line Status Epilepticus ICU Tertiary Center ICU Emergency Room Key Trial points: • Patients with convulsive status epilepticus • New dosing paradigm • Exception From Informed Consent community engagement underway • Sequential subject cohorts will evaluate dose and duration of treatment |

---

---

| | |
|:---|:---|
| &nbsp;&nbsp;![GRAPHIC](mrns-20230307xex99d2g032.jpg) | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;©2023 Marinus Pharmaceuticals. All Rights Reserved I RESET Trial Design in Established Status Epilepticus 32 Screening <30 min Enrollment Fail BZD IV ganaxolone infusion 1 IV ganaxolone infusion 3 SOC IV AED Convulsive SE (N=40) Ganaxolone bolus Ganaxolone bolus Ganaxolone bolus Seizures YES NO Seizures YES NO Seizures YES NO SOC Treatment Phase After each 5-subject cohort, will evaluate: Bolus – safety (sedation) / efficacy within 30 min Infusion – safety (sedation) / efficacy during ganaxolone infusion Duration – efficacy after infusion has been completed IV ganaxolone infusion 2 Dose optimization phase followed by double-blind phase with selected regimen Dose Optimization Phase |

---

---

| | |
|:---|:---|
| &nbsp;&nbsp;![GRAPHIC](mrns-20230307xex99d2g033.jpg) | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;©2023 Marinus Pharmaceuticals. All Rights Reserved I RAISE II: Phase 3 Trial in Refractory Status Epilepticus 33 1 Kapur et al. Randomized Trial of Three Anticonvulsant Medications for Status Epilepticus N Engl J Med 2019;381:2103-13. Benzodiazepine Administered IV AEDs (antiepileptic drugs) IV Anesthetics (Medically Established Status induced Coma) Epilepticus (ESE) Super Refractory Status Epilepticus (SRSE) Refractory Status Epilepticus (RSE) 1st Line 3rd Line Status Epilepticus 2nd Line ICU Tertiary Center ICU Emergency Room RAISE vs. RAISE II TARGET PATIENT POPULATION Failure of at least two or more treatments, either: Benzodiazepine(s) + > 1 IV AED OR > 2 IV AEDs (n=124) Failure of benzodiazepines and at least one IV AED's (RSE) (n=70) COMPARATOR Ganaxolone vs. Placebo in patients receiving background standard of care Ganaxolone vs. Placebo with concurrent IV AED initiation PRIMARY ENDPOINT Co-primary endpoints: (1)SE cessation within 30 min (2) no escalation to IV anesthesia within 36 hrs Responder analysis: SE cessation within 30 min and no escalation of care within 36 hrs Trial Goals: • Support potential European approval in RSE • Potential indication expansion opportunity (relative to the RAISE trial population) |

---

---

| | |
|:---|:---|
| &nbsp;&nbsp;![GRAPHIC](mrns-20230307xex99d2g034.jpg) | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Building Commercial Infrastructure for Future IV Launches |

---

---

| | |
|:---|:---|
| &nbsp;&nbsp;![GRAPHIC](mrns-20230307xex99d2g035.jpg) | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;©2023 Marinus Pharmaceuticals. All Rights Reserved I Clinical and Healthcare Costs Associated with RSE 35 Utilization and Cost Outcomes Metric Cohort 1 (≤ 1 IV AED) Cohort 2 (> 1 IV AED) Cohort 3 (≥ 1 IV anesthetic) All Unique RSE patient encounter, N (%) 14,694 (33.4) 10,140 (23.1) 19,154 (43.5) 43,988 (100) Hospital length of stay (LOS) (days) Mean\* 4.7 7.2 12.0 8.4 Median\* 3 4 8 5 ICU LOS (for ICU patients only) Mean\* 2.7 3.1 6.6 5.4 Median\* 2 2 4 3 Total hospital cost\* ($USD) Mean\* $11,532 $18,328 $41,858 $26,304 Median\* $6,812 $10,592 $24,105 $13,201 \* Indicates p<0.05 across all pairwise comparisons Source: Guterman EL 2021 JAMA Neurol. Ganaxolone may offer the potential to reduce hospital costs and length of stay Treatments that prevent progression to SRSE with its associated complications may reduce length of stay and hospital costs |

---

---

| | |
|:---|:---|
| &nbsp;&nbsp;![GRAPHIC](mrns-20230307xex99d2g036.jpg) | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;©2023 Marinus Pharmaceuticals. All Rights Reserved I Differentiated Market Access Strategy to Ensure Success for IV Ganaxolone Formulation (DRG), diagnosis-related group reimbursement 36 PRICING & REIMBURSEMENT • U.S./EU Pricing research initiated and ongoing • Determining New Technology Add-on Payment (NTAP) timing • Evaluating DRGs and other hospital payment systems DELIVERY & PATIENT ACCESS • Aligning on distribution pathway • Building plan for RSE and evaluating impact of ESE expansion VALUE PROPOSITION & HEALTH ECONOMIC MESSAGING • Assessing current treatment protocols • Evaluating burden of illness and hospital impact to expand & include cost avoidance metric CUSTOMER ENGAGEMENT • Considering impact of hospital networks to payer team • Ongoing assessment of potential hospital target segmentation underway |

---

---

| | |
|:---|:---|
| &nbsp;&nbsp;![GRAPHIC](mrns-20230307xex99d2g037.jpg) | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Financial Update  |

---

---

| | |
|:---|:---|
| &nbsp;&nbsp;![GRAPHIC](mrns-20230307xex99d2g038.jpg) | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;©2023 Marinus Pharmaceuticals. All Rights Reserved I Financial Overview 38 Analyst Coverage\*: Cantor Fitzgerald: Charles C. Duncan, Ph.D. Cowen: Joseph Thome, Ph.D. H.C. Wainwright & Co: Douglas Tsao Jefferies: Andrew Tsai JMP Securities: Jason N. Butler, Ph.D. Ladenburg Thalmann: Michael Higgins Oppenheimer: Jay Olson RBC: Brian Abrahams RW Baird: Brian Skorney SVB Securities: Marc Goodman Truist: Joon Lee, M.D., Ph.D. \*Note: Opinions, estimates, and forecasts of the individual analysts regarding Marinus do not represent opinions, estimates, and forecasts of Marinus. The listing above does not imply endorsement or concurrent with their information, conclusions, or recommendations. 1 Fully dilutive total includes impact of pre-funded warrants, convertible preferred stock and outstanding stock options and RSU's Investor Relations – Nasdaq: MRNS 2023 Full Year Guidance Revenues: • U.S. Ztalmy Net Product Revenue: $15 - $17 million • BARDA Revenue: $8 - $11 million Operating Expenses • FY 2023 GAAP operating expenses (SG&A and R&D) of between $165 - $175 million; total includes approximately $16 million of non-cash stock-based compensation Financial Summary (at December 31, 2022): • $240.6 million in cash and cash equivalents • $75 million in debt • 49.6 million shares outstanding; 59.0 million shares outstanding on a fully dilutive basis1 |

---

---

| | |
|:---|:---|
| &nbsp;&nbsp;![GRAPHIC](mrns-20230307xex99d2g039.jpg) | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;©2023 Marinus Pharmaceuticals. All Rights Reserved I Liquidity Overview 39 Note: All values shown are gross transactional proceeds 1 Marinus potential to draw subject to achievement of certain clinical and financial milestones Financial Summary (as of December 31, 2022): • $240.6 million in cash and cash equivalents • $75 million in debt from Oaktree Capital agreement; interest-only through May 2024, matures 2026 • $32.5 million revenue interest financing agreement with Sagard Healthcare Partners (executed Q4 2022) Q4 2022 Financing Activity: • Net equity raise of $64.5 million from issuance of 12.4 million shares of common stock and 2.1 million of pre-funded warrants • $32.5 million in gross proceeds from revenue interest financing agreement with Sagard • $10 million gross upfront fee from collaboration with Tenacia Biotechnology (Shanghai) Co., Ltd. for China market Completed & Potential Non-Dilutive Funding Options: FDA Approval March 2022 Q1 2022 $30 million Oaktree Capital Credit Funding - Drawn March '22 based upon FDA CDD approval Q3 2022 $110 million Sale of PRV - Completed August '22 Q4 2022 $32.5 million U.S. revenue interest financing - Completed October '22 Ongoing R&D Reimbursement: BARDA and Orion Corporation Q1 2022 Additional credit available under Oaktree Capital facility - Potential to draw $25 million of additional funding1 Orion & Tenacia Potential Milestones & Royalties Q4 2022 $10 million Tenacia partnership upfront (China) - Completed November '22 |

---

---

| | |
|:---|:---|
| &nbsp;&nbsp;![GRAPHIC](mrns-20230307xex99d2g040.jpg) | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Intellectual Property |

---

---

| | |
|:---|:---|
| &nbsp;&nbsp;![GRAPHIC](mrns-20230307xex99d2g041.jpg) | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;©2023 Marinus Pharmaceuticals. All Rights Reserved I Multiple Layers Of Potential Protection 41 Orphan drug designations for CDD and PCDH19 provide 7 and 10 years regulatory exclusivity in U.S. and EU, respectively. Orphan drug designation for SE provides 7 years regulatory exclusivity in U.S. Patents/ Patent Applications Expiration Date Status Epilepticus Method of Use Applications pending on potential dosing regimens for SRSE and ESE 2041/2042 U.S. patent granted on clinical regimen, applications pending in other jurisdictions 2040 Formulation Licensed Captisol® patents Through 2033 Applications pending on IV formulation 2036 CDKL5 Deficiency Disorder Method of Use Patents granted in U.S. and Europe (oral suspension) 2031 (if PTE granted) Licensed patent granted in U.S. for treatment of epileptic disorders 2037 Application pending on potential dosing regimen 2038/2041/2042 Formulation Patents granted in U.S. and Europe (oral suspension) 2031 (if PTE granted) Tuberous Sclerosis Complex Method of Use Application pending on potential dosing regimen 2040/2041/2042 Formulation Patents granted in U.S. and Europe (oral suspension) 2031 (if PTE granted) Second Generation Ganaxolone Formulation Application pending on potential second generation formulations 2042/2043 |

---