UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, DC 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):  April 16, 2015

Momenta Pharmaceuticals, Inc.

(Exact Name of Registrant as Specified in Charter)

(617) 491-9700

(Registrant’s telephone number,
including area code)

Not applicable

(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 (see General Instruction A.2. below):

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 8.01. Other Events.

On April 16, 2015, Momenta Pharmaceuticals, Inc. (“Momenta”) issued a press release announcing that the U.S. Food and Drug Administration has granted marketing approval of the Abbreviated New Drug Application for once-daily GlatopaTM (glatiramer acetate injection) 20 mg/mL, a generic equivalent of COPAXONE®.  Glatopa, formerly M356, was developed under the Collaboration and License Agreement, dated June 13, 2007, by and between Momenta and Sandoz AG.

A copy of the press release is furnished as Exhibit 99.1 and is incorporated herein by reference.

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.

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EXHIBIT INDEX

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