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 31, 2017

MARINUS PHARMACEUTICALS, INC.

(Exact name of registrant as specified in its charter)

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:

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

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

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

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

Item 1.01.                                        Entry into a Material Definitive Agreement.

On March 31, 2017, we entered into a License Agreement and a Supply Agreement with CyDex Pharmaceuticals, Inc.  Under the terms of the License Agreement, CyDex has granted us an exclusive license to use CyDex’s Captisol drug formulation system and related intellectual property in connection with the development and commercialization of ganaxolone in any and all therapeutic uses in humans, with some exceptions.

As consideration for this license, we paid an upfront fee and are required to make additional payments in the future upon achievement of various specified clinical and regulatory milestones.  We will also be required to pay royalties to CyDex on sales of ganaxolone, if successfully developed, in the low-to-mid single digits based on levels of annual net sales.

Under the terms of the Supply Agreement, we are required to purchase all of our requirements for Captisol with respect to ganaxolone from CyDex, and CyDex is required to supply us with Captisol for such purposes, subject to certain limitations.

A copy of the License Agreement and Supply Agreement, with certain terms omitted, are attached as Exhibits 10.1 and 10.2 to this report and is incorporated herein by reference.  Application has been made to the Securities and Exchange Commission for confidential treatment of certain provisions.  Omitted material for which confidential treatment has been requested has been filed separately with the Securities and Exchange Commission.  The descriptions of the License Agreement and Supply Agreement are a summary only and are qualified in their entirety by reference to Exhibits 10.1 and 10.2.

Item 9.01.                                        Financial Statements and Exhibits.

(d)     Exhibits

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SIGNATURE

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.

Date:  April 6, 2017

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