Ernexa Therapeutics Inc.

As filed with the Securities and Exchange Commission on February 2, 2026.

Registration No. 333-

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORMS-1

REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933

(Exact name of registrant as specified in its charter)

1035 Cambridge Street, Suite 18A

Cambridge, MA 02141

(617) 798-6700

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

Sanjeev Luther

President and Chief Executive Officer

1035 Cambridge Street, Suite 18A

Cambridge, MA 02141

(617) 798-6700

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

Copies to:

**Approximate date of commencement of proposed sale to the public:**From time to time after the date 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, a non-accelerated filer, a 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 Commission, acting pursuant to said Section 8(a), may determine.

The information in this prospectus is not complete and may be changed. These securities may not be sold until the registration statement filed with the Securities and Exchange Commission is effective. This prospectus is not an offer to sell these securities, and it is not soliciting an offer to buy these securities in any jurisdiction where the offer or sale is not permitted.

Up to [*] Shares of Common Stock

Up to [] Common Warrants to Purchase Up to [] Shares of Common Stock

Up to [*] Shares of Common Stock Underlying the Common Warrants

Up to [*] Shares of Common Stock Issuable to the Placement Agent

We are offering on a best-efforts basis up to [] shares of our common stock, par value $0.005 (the “Common Stock”), together with common stock purchase warrants (the “Common Warrants”) to purchase up to [] shares of Common Stock. Each share of Common Stock is being sold together with a Common Warrant to purchase one share of Common Stock. The shares of Common Stock and Common Warrants are immediately separable and will be issued separately in this offering, but must be purchased together in this offering.

The combined public offering price for each share of Common Stock and accompanying Common Warrant is $[] per share of Common Stock and accompanying Common Warrant (65% of the closing price of our Common Stock on The Nasdaq Capital Market (“Nasdaq”) on [], 2026). Each Common Warrant will have an exercise price per share equal to $[] (closing price of our Common Stock on [], 2026) and will be immediately exercisable. The Common Warrants will expire on the earlier of (i) the five (5)-year anniversary of the original issuance date or (ii) the 180 th calendar day following the public release by the Company of clinical trial data from the first cohort of the Phase 1 study of ERNA-101 (the “Exercise Period”).

We have engaged Brookline Capital Markets, a division of Arcadia Securities, LLC, as exclusive placement agent (“Brookline,” or the “Placement Agent”), to use its reasonable best efforts to arrange for the sale of the securities offered by this prospectus. The Placement Agent is not purchasing or selling any of the securities we are offering, and the Placement Agent is not required to arrange the purchase or sale of any specific number or dollar amount of securities. We have agreed to pay to the Placement Agent the placement agent fees set forth in the table below, which assumes that we sell all of the securities offered by this prospectus.

In addition to the cash compensation described elsewhere in this prospectus, we have agreed to issue to the Placement Agent or its designees, as additional compensation, up to [*] shares of our Common Stock, which is equal to 1.5% of the aggregate number of shares of Common Stock sold in this offering, provided that with respect to sales to certain existing investors, such percentage shall be 0.5%. These shares are referred to herein as the “Agent’s Shares.” The Agent’s Shares have been deemed compensation by the Financial Industry Regulatory Authority (“FINRA”) and will be subject to a 180-day lock-up period from the commencement of sales of securities in this offering pursuant to FINRA Rule 5110(e)(1)(A). See “Plan of Distribution” for additional information.

The securities will be offered at a fixed price and are expected to be issued in a single closing. The offering will terminate on February 27, 2026, unless (i) the closing occurs prior thereto or (ii) we decide to terminate the offering prior thereto (which we may do at any time in our discretion). Investors purchasing securities offered hereby will have the option to execute a securities purchase agreement with us. We expect that the closing of the offering will occur one trading day after we price the securities offered hereby. When we price the securities, we will simultaneously enter into securities purchase agreements relating to the offering with those investors who so choose.

While the offering is ongoing, investors may submit subscription agreements to the Placement Agent. Subscriptions are irrevocable, and subscribers cannot withdraw their funds during the offering period. See the section titled “Plan of Distribution” for more details about the offering, the process of subscriptions and the subscription agreements.

Because this is a best-efforts offering, the Placement Agent does not have an obligation to purchase any securities, and, as a result, there is a possibility that we may not be able to sell the securities. There is no minimum offering requirement as a condition of closing of this offering. Because there is no minimum offering amount required as a condition to closing this offering, we may sell fewer than all of the securities offered hereby, which may significantly reduce the amount of proceeds received by us, and investors in this offering will not receive a refund in the event that we do not sell an amount of securities sufficient to pursue our business goals described in this prospectus. Further, any proceeds from the sale of securities offered by us will be available for our immediate use, despite uncertainty about whether we would be able to use such funds to effectively implement our business plan. See the section titled “Risk Factors” for more information.

Our Common Stock is listed on Nasdaq under the symbol “ERNA.” On January 30, 2026, the last reported sale price of our Common Stock on Nasdaq was $1.22 per share. The actual public offering price per share of Common Stock and accompanying Common Warrant will be determined between us, the Placement Agent and the investors in this offering at the time of pricing, and may be at a discount to the current market price for our Common Stock. We have applied to list the Common Warrants on Nasdaq under the symbol “ERNAW.” No assurance can be given that our application will be approved or that even if approved, an active trading market for the Common Warrants will develop.

Investing in our securities involves risks. You should review carefully the risks and uncertainties described under the heading “Risk Factors” contained in this prospectus and under similar headings in this prospectus, as described beginning on page 8 of this prospectus.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of the securities to be issued under this prospectus or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

Delivery of the securities is expected to be made on or about , 2026.

Exclusive Placement Agent

Brookline Capital Markets

a division of Arcadia Securities, LLC

The date of this prospectus is , 2026

TABLE OF CONTENTS

i