MEDICINOVA INC

S-11 d163359ds1.htm S-1

As filed with the Securities and Exchange Commission on August 22, 2025

Registration No. 333-

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

**FORMS-1 **

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

MEDICINOVA, INC.

(Exact name of registrant as specified in its charter)

4275 Executive Square, Suite 300

La Jolla, California 92037

(858) 373-1500

(Address, including zip code, and telephone number, including area code, of registrant’s principal executive offices)

Yuichi Iwaki, M.D., Ph.D.

President and Chief Executive Officer

MEDICINOVA, INC.

4275 Executive Square, Suite 300

La Jolla, California 92037

(858) 373-1500

(Name, address, including zip code, and telephone number, including area code, of agent for service)

Copies of all communications, including communications sent to agent for service, should be sent to:

Kirt W Shuldberg, Esq.

John E. Maciejewski, Esq.

Gunderson Dettmer Stough Villeneuve

Franklin & Hachigian, LLP

3570 Carmel Mountain Rd., Suite 200

San Diego, California 92130

(858) 436-8000

Approximate date of commencement of proposed sale to the public: From time to time after this Registration Statement becomes effective.

If any of the securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933 check the following box. ☒

If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, please check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ☐

If this Form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ☐

If this Form is a post-effective amendment filed pursuant to Rule 462(d) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, anon-accelerated filer, smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act.

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 7(a)(2)(B) of the Securities Act. ☐

THE REGISTRANT HEREBY AMENDS THIS REGISTRATION STATEMENT ON SUCH DATE OR DATES AS MAY BE NECESSARY TO DELAY ITS EFFECTIVE DATE UNTIL THE REGISTRANT SHALL FILE A FURTHER AMENDMENT WHICH SPECIFICALLY STATES THAT THIS REGISTRATION STATEMENT SHALL THEREAFTER BECOME EFFECTIVE IN ACCORDANCE WITH SECTION 8(a) OF THE SECURITIES ACT OF 1933, AS AMENDED, OR UNTIL THE REGISTRATION STATEMENT SHALL BECOME EFFECTIVE ON SUCH DATE AS THE SECURITIES AND EXCHANGE COMMISSION, ACTING PURSUANT TO SAID SECTION 8(a), MAY DETERMINE.

The information in this preliminary prospectus is not complete and may be changed. The selling stockholder may not sell these securities until the registration statement filed with the Securities and Exchange Commission is effective. This preliminary prospectus is not an offer to sell these securities and we are not soliciting an offer to buy these securities in any state or jurisdiction where the offer or sale is not permitted.

SUBJECT TO COMPLETION, DATED AUGUST 22, 2025.

PRELIMINARY PROSPECTUS

MediciNova, Inc.

25,000,000 Shares of Common Stock

This prospectus relates to the offer and sale of up to 25,000,000 shares of our common stock, par value $0.001 per share, by YA II PN, LTD. (the “YA” or the “selling stockholder”), a Cayman Islands exempt limited partnership.

The shares of common stock being offered by the selling stockholder are being issued pursuant to the Standby Equity Purchase Agreement, dated July 30, 2025, which we entered into with YA (the “Purchase Agreement”). We are not selling any securities under this prospectus and will not receive any of the proceeds from the sale of our shares by the selling stockholder. However, we may receive up to $30.0 million in aggregate gross proceeds from sales of our shares to YA that we may make under the Purchase Agreement, from time to time during the 36 months following the execution of the Purchase Agreement (the “Advance Shares”. The shares that may be offered pursuant to this prospectus represent Advance Shares, which would be purchased by YA from time to time pursuant to the Purchase Agreement at a price equal to 97% of the lowest of the three daily volume weighted average prices(the “VWAPs”), during a pricing period as set forth in the Purchase Agreement and would be subject to certain limitations.

The selling stockholder may sell the shares of common stock included in this prospectus in a number of different ways and at varying prices. We provide more information about how the selling stockholder may sell the shares in the section entitled “Plan of Distribution”. The selling stockholder is an “underwriter” within the meaning of Section 2(a)(11) of the Securities Act of 1933, as amended (the “Securities Act”).

The selling stockholder will pay all brokerage fees and commissions and similar expenses in connection with the offer and sale of the shares by the selling stockholder pursuant to this prospectus. We will pay the expenses (except brokerage fees and commissions and similar expenses) incurred in registering under the Securities Act the offer and sale of the shares included in this prospectus by the selling stockholder. See section entitled “Plan of Distribution”.

Our common stock is listed on the Nasdaq Capital Market under the symbol “MNOV”. On August 21, 2025, the last reported sale price of our common stock on the Nasdaq Capital Market was $1.29 per share.

Investing in our securities involves risks. See the section entitled “Risk Factors” included in this prospectus.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or passed upon the adequacy or accuracy of this prospectus. Any representation to the contrary is a criminal offense.

The date of this prospectus is , 2025.