Profusa, Inc.

As filed with the Securities and Exchange Commission on October 9, 2025.

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)

**626 Bancroft Way

Suite A

Berkeley, CA 94710

(925) 997-6925

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

Ben C. Hwang

Chief Executive Officer

**626 Bancroft Way

Suite A

Berkeley, CA 94710

(925) 997-6925

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

Copies to:

**Ralph V. De Martino, Esq.

Marc Rivera, Esq.

ArentFox Schiff LLP

1717 K Street, NW

Washington, DC 20006

Phone: (202) 724-6847

**Approximate date of commencement of proposed sale to the public:**As soon as practicable 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, a non-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.☐

This registration statement shall hereafter become effective in accordance with the provisions of Section 8(a) of the Securities Act of 1933.

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, nor does it seek an offer to buy these securities in any jurisdiction where the offer or sale is not permitted.

SUBJECT TO COMPLETION, DATED october 8, 2025.

PRELIMINARY PROSPECTUS

42,594,048 Shares of Common Stock

This prospectus relates to the resale, from time to time, by the Selling Stockholders identified in this prospectus under the caption “Selling Stockholders,” of up to 42,594,048 shares of common stock, par value $0.0001 per share, of the Company (the “Common Stock”) comprising: (a) up to 42,211,548 shares of Common Stock by Ascent Partners Fund LLC, whom we refer to in this prospectus as “Ascent,” pursuant to a common stock purchase agreement, dated as of July 28, 2025, we entered into with Ascent, which we refer to in this prospectus as the Purchase Agreement; and (b) up to 382,500 shares of Common Stock issued to certain parties in satisfaction of transaction costs incurred in connection with the Business Combination we completed on July 11, 2025.

In our registration statement, filed on August 22, 2025 and declared effective on August 25, 2025, we previously registered the resale of up to 8,970,830 shares by Ascent pursuant to the Purchase Agreement. This prospectus registers the resale of up to an additional 42,211,548 shares of Common Stock (the “Purchase Shares”) that we may, in our sole discretion, elect to sell to Ascent, from time to time over a period of up to 36 months from and after the Effective Date (defined below) pursuant to the Purchase Agreement. Ascent is deemed to be an “underwriter” within the meaning of Section 2(a)(11) of the Securities Act of 1933, as amended, or the Securities Act.

We are registering the offer and sale and/or resale of these securities to satisfy certain registration obligations we have and certain registration rights we have granted. The Selling Stockholders may offer all or part of the Resale Securities for resale from time to time through public or private transactions, at either prevailing market prices or at privately negotiated prices. The Resale Securities are being registered to permit the Selling Stockholders to sell Resale Securities from time to time, in amounts, at prices and on terms determined at the time of offering. The Selling Stockholders may sell the Resale Securities through ordinary brokerage transactions, in underwritten offerings, directly to market makers of our securities or through any other means described in the section entitled “Plan of Distribution” herein. In connection with any sales of Resale Securities offered hereunder, the Selling Stockholders, any underwriters, agents, brokers or dealers participating in such sales may be deemed to be “underwriters” within the meaning of the Securities Act, or the Exchange Act. We are registering the Resale Securities for resale by the Selling Stockholders, or their donees, pledgees, transferees, distributees or other successors**-**in-interest selling our Common Stock received after the date of this prospectus from the Selling Stockholders as a gift, pledge, partnership distribution or other transfer.

The Selling Stockholders may sell the shares of our common stock offered by this prospectus from time to time on terms to be determined at the time of sale through ordinary brokerage transactions or through any other means described in this prospectus under the caption*“Plan of Distribution.”* The shares of common stock may be sold at fixed prices, at market prices prevailing at the time of sale, at prices related to prevailing market price or at negotiated prices.

We will pay the expenses incurred in registering under the Securities Act the offer and sale of the shares of Common Stock to which this prospectus relates by the Selling Stockholders, including legal and accounting fees. See*“Plan of Distribution — Offer and Resale of Common Stock by the Selling Stockholders”* beginning on page 145.

Our common stock is listed on the Nasdaq Global Market under the symbol “PFSA.” On October 7, 2025, the last sale price for our common stock as reported on the Nasdaq Global Market was $0.33 per share.

We are a “smaller reporting company” as defined under the federal securities laws and, as such, have elected to comply with certain reduced public company reporting requirements for this prospectus and may elect to do so in future filings.

Investing in our securities involves a high degree of risk. See the section entitled*“Risk Factors”* appearing on page 5 of this prospectus for a discussion of information that should be considered in connection with an investment in our securities.

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

The date of this prospectus is__________, 2025

TABLE OF CONTENTS

You should rely only on the information contained in this prospectus or any amendment or supplement to this prospectus. This prospectus is an offer to sell only the securities offered hereby, but only under the circumstances and in jurisdictions where it is lawful to do so. Neither we nor the Selling Stockholders have authorized anyone to provide you with information different from that contained in this prospectus or any amendment or supplement to this prospectus. Neither we nor the Selling Stockholders take any responsibility for, or can provide any assurance as to the reliability of, any information other than the information in this prospectus or any amendment or supplement to this prospectus. The information in this prospectus or any amendment or supplement to this prospectus is accurate only as of its date, regardless of the time of delivery of this prospectus or any amendment or supplement to this prospectus, as applicable, or any sale of the securities offered by this prospectus. Our business, financial condition, results of operations and prospects may have changed since that date.

For Investors Outside the United States: The Selling Stockholders are offering to sell, and seeking offers to buy, the securities offered by this prospectus only in jurisdictions where offers and sales are permitted. Neither we nor the Selling Stockholders have done anything that would permit this offering or the possession or distribution of this prospectus in any jurisdiction where action for that purpose is required, other than in the United States. Persons outside the United States who come into possession of this prospectus must inform themselves about, and observe any restrictions relating to, the offering of the securities offered by this prospectus and the distribution of this prospectus outside the United States.

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