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): November 29, 2017

MELINTA THERAPEUTICS, INC.

(Exact name of registrant as specified in its charter)

Registrant’s telephone number, including area code (312) 767-0291

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:

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. ☐

On November 29, 2017, Melinta Therapeutics, Inc. (“Melinta” or the “Company”) issued a press release (the “Press Release”) announcing its entry into an agreement (the “Agreement”) on November 28, 2017 with The Medicines Company (“MedCo”) to acquire the capital stock of certain subsidiaries of MedCo and certain other assets related to MedCo’s infectious disease business unit.

The foregoing description of the Agreement is qualified in its entirety by reference to the Press Release, a copy of which is attached hereto as Exhibit 99.1.

(d) Exhibits

Cautionary Note Regarding Forward-Looking Statements

Certain statements in this communication constitute “forward-looking statements” within the meaning of Section 27A of the Securities Act and Section 21E of the Securities Exchange Act and are usually identified by the use of words such as “anticipates,” “believes,” “estimates,” “expects,” “intends,” “may,” “plans,” “projects,” “seeks,” “should,” “will,” and variations of such words or similar expressions. We intend these forward-looking statements to be covered by the safe harbor provisions for forward-looking statements contained in Section 27A of the Securities Act and Section 21E of the Securities Exchange Act and are making this statement for purposes of complying with those safe harbor provisions. These forward-looking statements reflect our current views about our plans, intentions, expectations, strategies and prospects, which are based on the information currently available to us and on assumptions we have made. Although we believe that our plans, intentions, expectations, strategies and prospects as reflected in or suggested by those forward-looking statements are reasonable, we can give no assurance that the plans, intentions, expectations or strategies will be attained or achieved. Furthermore, actual results may differ materially from those described in the forward-looking statements and will be affected by a variety of risks and factors that are beyond our control.

Risks and uncertainties for Melinta include, but are not limited to: inability to complete the proposed transactions; liquidity and trading market for shares prior to and following the consummation of the proposed transactions; costs and potential litigation associated with the proposed transactions; failure or delay in obtaining required approvals by governmental or quasi-governmental entity necessary to consummate the proposed transactions; failure to satisfy other conditions to the closing of the proposed transactions; risks related to the costs, timing and regulatory review of the Company’s studies and clinical trials, including its ability to address the issues identified by the FDA in the complete response letter relating to Melinta’s new drug applications for solithromycin for community acquired bacterial pneumonia; uncertainties in obtaining successful clinical results for product candidates and unexpected costs that may result therefrom; inability or the delay in obtaining required regulatory approvals for product candidates, which may result in unexpected cost expenditures; failure to realize any value of certain product candidates developed and being developed, in light of inherent risks and difficulties involved in successfully bringing product candidates to market; inability to develop new product candidates and support existing products; inability to commercialize and launch any product candidate that receives regulatory approval, including Baxdela; the Company’s anticipated capital expenditures, its estimates regarding its capital requirements and its need for future capital; uncertainties of cash flows and inability to meet working capital needs; cost reductions that may not result in anticipated level of cost savings or cost reductions prior to or after the consummation of the proposed transactions; the approval by the FDA and EMA and any other similar foreign regulatory authorities of other competing or superior products brought to market; risks resulting from unforeseen side effects; risk that the market for the Company’s products may not be as large as expected; inability to obtain, maintain and enforce patents and other intellectual property rights or the unexpected costs associated with such enforcement or litigation; inability to obtain and maintain commercial manufacturing arrangements with third party manufacturers or establish commercial scale manufacturing capabilities; loss of or diminished demand from one or more key customers or distributors; unexpected cost increases and pricing pressures; the possibility of economic recession and its negative impact on customers, vendors or suppliers; and risks associated with the possible failure to realize certain benefits of the proposed transactions, including future financial, tax, accounting treatment, and operating results. Many of these factors that will determine actual results are beyond Melinta’s ability to control or predict.

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Other risks and uncertainties are more fully described in our Annual Report on Form 10-K for the year ended December 31, 2016, as amended by Form 10-K/A, filed with the SEC on April 13, 2017, and in other filings that Melinta makes and will make with the SEC in connection with the proposed transactions, including the proxy statement described below under “Important Information and Where to Find It.” Existing and prospective investors are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date hereof. The statements made in this press release or presentation speak only as of the date stated herein, and subsequent events and developments may cause our expectations and beliefs to change. While we may elect to update these forward-looking statements publicly at some point in the future, we specifically disclaim any obligation to do so, whether as a result of new information, future events or otherwise, except as required by law. These forward-looking statements should not be relied upon as representing our views as of any date after the date stated herein.

Participants in this Transaction:

Melinta and certain of its directors and executive officers may be deemed to be participants in the solicitation of proxies from Melinta’s stockholders in connection with the proposed transactions. Additional information regarding persons who may, under the rules of the SEC, be deemed to be participants in the solicitation of Melinta stockholders in connection with the proposed transactions, and a description of their direct and indirect interest, whether as security holders, directors or employees of Melinta or otherwise, which may be different from those of Melinta’s stockholders generally, will be set forth in the definitive proxy statement filed with the SEC in connection with the proposed transactions. You can find information about Melinta’s directors and executive officers in Melinta’s Schedule 14F-1 filed with the SEC on October 24, 2017, as supplemented on November 16, 2017.

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Important Information and Where to Find It

Melinta will file a proxy statement with the SEC in connection with the proposed transactions. The proxy statement will be sent to the stockholders of Melinta. Melinta stockholders are advised to read the proxy statement when it becomes available, because it will contain important information about Melinta, and the proposed transactions. When filed, this document and other documents relating to the proposed transactions filed by Melinta can be obtained, free of charge, at the SEC’s website (http://www.sec.gov), at the company’s website (http://ir.melinta.com/), or by writing to the Secretary, Melinta Therapeutics, Inc., at ir@melinta.com.

This communication is being provided for informational purposes only and does not constitute (i) an offer to purchase, nor a solicitation of an offer to sell, subscribe for or buy any securities, (ii) an offer to exchange any securities or (iii) the solicitation of any vote for approval of any transaction. There shall not be any offer, solicitation, sale or exchange of any securities in any state or other jurisdiction in which such offer, solicitation, sale, or exchange is not permitted.

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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.

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