As filed with the Securities and Exchange Commission on July 19, 2021

Registration No. 333-                

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM S-1

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

HCW BIOLOGICS INC.

(Exact name of Registrant as specified in its charter)

2929 N Commerce Parkway

Miramar, FL 33025

(954) 842-2024

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

Hing C. Wong, Ph.D.

Chief Executive Officer

HCW Biologics Inc.

2929 N Commerce Parkway

Miramar, FL 33025

(954) 842-2024

(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:

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.  ☒ 333-256510

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 Securities Exchange Act of 1934

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 to Section 7(a)(2)(B) of the Securities Act.   ☐

CALCULATION OF REGISTRATION FEE

The Registration Statement shall become effective upon filing in accordance with Rule 462(b) promulgated under the Securities Act of 1933, as amended.

EXPLANATORY NOTE

This Registration Statement is being filed pursuant to Rule 462(b) under the Securities Act of 1933, as amended (the “Securities Act”), for the sole purpose of increasing the aggregate number of shares of common stock offered by HCW Biologics Inc. (the “Registrant”) to be registered for sale by 1,610,000 shares, 241,500 of which are subject to purchase upon exercise of the underwriters’ option to purchase additional shares of the Registrant’s common stock. The additional shares that are being registered for issuance and sale are in an amount and at a price that together represent no more than 20% of the maximum aggregate offering price set forth in the Calculation of Registration Fee table contained in the Registration Statement on Form S-1, as amended (File No. 333-256510) (the “Initial Registration Statement”). The contents of the Initial Registration Statement, filed by the Registrant with the Securities and Exchange Commission (the “Commission”) pursuant to the Securities Act, which was declared effective by the Commission on July 19, 2021, are incorporated by reference into this Registration Statement.

The required opinion and consents are listed on the Exhibit Index attached hereto and filed herewith.

EXHIBIT INDEX

SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, the registrant has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the city of Miramar, State of Florida on July 19, 2021.

Pursuant to the requirements of the Securities Act of 1933, as amended, this Registration Statement has been signed by the following persons in the capacities and on the dates indicated:

Exhibit 5.1

				Orrick, Herrington & Sutcliffe LLP The Orrick Building 405 Howard Street San Francisco, CA 94105   +1 415 773 5700 orrick.com

July 19, 2021

HCW Biologics Inc.

2929 N Commerce Parkway

Miramar, Florida 33025

Ladies and Gentlemen:

We are acting as counsel for HCW Biologics Inc., a Delaware corporation (the “Company”), in connection with (i) the registration statement on Form S-1 filed by the Company with the Securities and Exchange Commission (the “Commission”) on May 26, 2021, as amended (the “Prior Registration Statement”), under the Securities Act of 1933, as amended (the “Securities Act”), and (ii) a second Registration Statement on Form S-1 filed pursuant to Rule 462(b) promulgated under the Securities Act (the “462(b) Registration Statement”, and together with the Prior Registration Statement, the “Registration Statement”). This opinion letter is being furnished to you in connection with your filing of the 462(b) Registration Statement relating to the registration of the offering by the Company of up to 1,610,000 shares (the “Shares”) of the Company’s common stock, $0.0001 par value per share, including Shares purchasable by the underwriters upon their exercise of the option granted to the underwriters by the Company to purchase additional shares. This opinion is in addition to our opinion that was filed as Exhibit 5.1 to the Company’s Prior Registration Statement.

In connection with rendering the opinion set forth below, we have examined and relied upon originals or copies, certified or otherwise identified to our satisfaction, of instruments, documents, and records which we deemed relevant and necessary for the purpose of rendering our opinion set forth below. In such examination, we have assumed the following: (a) the authenticity of original documents and the genuineness of all signatures, (b) the conformity to the originals of all documents submitted to us as copies, (c) the representations of officers and employees are correct as to questions of fact, (d) the Registration Statement has been declared effective pursuant to the Securities Act and (e) a pricing committee of the board of directors will have taken action necessary to set the sale price of the Shares.

Our opinion herein is limited to the General Corporation Law of the State of Delaware.

Based upon the foregoing, we are of the opinion that the Shares to be issued and sold by the Company have been duly authorized and, when such Shares are issued and paid for in accordance with the terms of the Underwriting Agreement, will be validly issued, fully paid and non-assessable.

HCW Biologics Inc.

July 19, 2021

Page 2

We consent to the filing of this opinion as an exhibit to the Registration Statement, and we further consent to the use of our name under the caption “Legal matters” in the Registration Statement and the prospectus that forms a part thereof. In giving these consents, we do not thereby admit that we are within the category of persons whose consent is required under Section 7 of the Securities Act or the Rules and Regulations of the Commission promulgated thereunder, nor do we thereby admit that we are “experts” within the meaning of such term as used in the Securities Act with respect to any part of the Registration Statement, including this opinion letter as an exhibit or otherwise.

Very truly yours,

/s/ Orrick, Herrington & Sutcliffe LLP

ORRICK, HERRINGTON & SUTCLIFFE LLP

Exhibit 23.1

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

We have issued our report dated April 16, 2021, except for Note 15 as to which the date is July 6, 2021, with respect to the financial statements of HCW Biologics Inc. contained in the Registration Statement on Form S-1, as amended (File No. 333- 256510), which are incorporated by reference in this Registration Statement on Form S-1MEF. We consent to the incorporation by reference of the aforementioned report in this Registration Statement, and to the use of our name as it appears under the caption “Experts” in the prospectus incorporated by reference in this Registration Statement.

/s/ GRANT THORNTON LLP

Miami, Florida

July 19, 2021