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): October 28, 2019

MEDICINOVA, INC.

(Exact name of registrant as specified in its charter)

Registrant’s telephone number, including area code: (858) 373-1500

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):

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

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).

On October 28, 2019 (Japanese Standard Time), MediciNova, Inc. (the “Company”) filed with the Tokyo Stock Exchange, an amended version of a Japanese report referred to as “Kessan Tanshin,” which contained the Company’s financial results for the quarter ended September 30, 2019 (the “Tanshin”).

The Tanshin is substantially the same as the Company’s Quarterly Report on Form 10-Q for the quarter ended September 30, 2019, except the following supplemental information is provided:

Expected basic and diluted loss per share for the year ending December 31, 2019 is $0.33*

Note to financial results forecast: The above estimates are based on certain assumptions made by the Company’s management as of the date hereof. These assumptions are based on management’s experience and perception of current conditions, trends, expected future developments and other factors believed to be appropriate in the circumstances. Such estimates are subject to a number of assumptions, risks and uncertainties, many of which are beyond the control of the Company and may cause the Company’s actual results to differ materially from the above estimates. Although the Company’s management believes that these assumptions are reasonable, the Company cannot assure you that the Company’s business will develop in accordance with these estimates. Investors are cautioned not to rely on these estimates as it is highly likely that actual results will differ, perhaps materially. These risks include the risk factors detailed in the Company’s Securities and Exchange Commission filings, including the Company’s Annual Report on Form 10-K for the year ended December 31, 2018. The Company’s independent auditors have not compiled or been involved in the preparation of the forecasted financial results for fiscal year 2019. Accordingly, they assume no responsibility for the accuracy or presentation of this information.

The information in this Current Report is being furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of that Section. The information in this Current Report shall not be deemed incorporated by reference in any filing under the Securities Act of 1933, as amended, or the Exchange Act, except as expressly set forth by specific reference in such a filing.

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The Tanshin may include forward-looking statements that involve a number of risks and uncertainties, many of which are beyond the Company’s control. The Company’s actual results may differ from those anticipated or expressed in these forward-looking statements as a result of various factors, including those set forth in the Company’s Annual Report on Form 10-K for the year ended December 31, 2018 filed with the Securities and Exchange Commission and its subsequent periodic reports on Forms 10-Q and 8-K, and the differences may be material. Forward-looking statements discuss matters that are not historical facts. Forward-looking statements include discussions regarding our operating strategy, growth strategy, licensing and acquisition strategy, cost savings initiatives, industry and economic conditions, market factors, financial condition, liquidity and capital resources, results of operations, expected progress of the development of our product candidates, potential licensing, collaboration and partnering plans, anticipated trends and challenges in our business and the markets in which we operate, competitive position, intellectual property protection, critical accounting policies and the impact of recent accounting pronouncements. For example, we make forward-looking statements regarding the potential for our product candidates to receive regulatory approval for one or more indications on a timely basis or at all; the progress and results of pending clinical trials for certain of our product candidates, including any delays in commencing or completing enrollment for our ongoing or planned clinical trials; plans for future clinical trials and regulatory submissions; unexpected adverse side effects or inadequate therapeutic efficacy of certain of our product candidates that could delay or prevent regulatory approval or commercialization or that could result in product liability claims; other difficulties or delays in development, testing, manufacturing and marketing of and obtaining regulatory approval for our product candidates; the scope and validity of patent protection for our product candidates; the market potential for our target markets and our ability to compete; the potential to attract and maintain relationships with one or more strategic partners and terms of any related transactions; intense competition if any of our product candidates are ever commercialized; the potential impact of uncertainties in the credit and capital markets or a future deterioration of these markets on our cash reserves; and our ability to raise sufficient capital or debt financing when needed, or at all. Such forward-looking statements include statements preceded by, followed by or that otherwise include the words “may,” “might,” “will,” “intend,” “should,” “could,” “can,” “would,” “expect,” “believe,” “estimate,” “anticipate,” “predict,” “potential,” “plan” or similar words. For all forward-looking statements, we claim the protection of the safe harbor for forward-looking statements contained in the Private Securities Litigation Reform Act of 1995. You should not rely unduly on these forward-looking statements, which speak only as of the date on which they are made. The Company undertakes no obligation to revise or update publicly any forward-looking statements, whether as a result of new information, future events or otherwise, unless required by law.

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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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