As filed with the Securities and Exchange Commission on July 10, 2020

Registration No. 333-                

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM S-1

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

Nkarta, Inc.

(Exact name of registrant as specified in its charter)

6000 Shoreline Court, Suite 102

South San Francisco, CA 94080

415-582-4923

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

Paul J. Hastings

Chief Executive Officer

Nkarta, Inc.

6000 Shoreline Court, Suite 102

South San Francisco, CA 94080

415-582-4923

(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 the effective date of this Registration Statement.

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, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.  ☒ 333-239301

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 checkmark 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. ☐

CALCULATION OF REGISTRATION FEE

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

EXPLANATORY NOTE AND INCORPORATION OF CERTAIN INFORMATION BY REFERENCE

Nkarta, Inc., a Delaware corporation (the “Registrant”), is filing this Registration Statement with the Securities and Exchange Commission (the “Commission”) pursuant to Rule 462(b) under the Securities Act of 1933, as amended (the “Securities Act”), with respect to the registration of additional shares of common stock, par value $0.0001 per share (the “Common Stock”), of the Registrant. This Registration Statement relates to the Registrant’s Registration Statement on Form S-1, as amended (File No. 333-239301) (the “Prior Registration Statement”), initially filed by the Registrant on June 19, 2020 and declared effective by the Commission on July 9, 2020. The contents of the Prior Registration Statement, including all amendments and exhibits thereto, are incorporated by reference into this Registration Statement.

This Registration Statement is being filed solely for the purpose of increasing the number of shares to be offered in the public offering by 1,150,000 shares of Common Stock, which includes 150,000 shares of Common Stock that may be sold pursuant to the underwriters’ option to purchase additional shares. The shares of Common Stock that are being registered for sale hereby are in an amount and at a price that together represent no more than 20% of the maximum aggregate number of shares set forth in the Calculation of Registration Fee table contained in the Prior Registration Statement.

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

PART II

Information Not Required in Prospectus

The following documents are filed as exhibits to this Registration Statement, and all other exhibits previously filed as exhibits to the Registrant’s Registration Statement on Form S-1, as amended (File No. 333-239301), are incorporated by reference into, and shall be deemed to be a part of, this filing.

SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, as amended, the registrant has duly caused this Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the city of South San Francisco, on this 10th day of July, 2020.

SIGNATURES

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 held on the dates indicated.

Exhibit 23.1

Consent of Independent Registered Public Accounting Firm

We consent to the incorporation by reference in the Registration Statement on Form S-1 filed pursuant to Rule 462(b) of the Securities Act of 1933 of the reference to our firm under the caption “Experts” and to the incorporation by reference of our report dated April 17, 2020 (except for the retroactive effect of the 1-for-3.7 reverse stock split as described in Note 2, as to which the date is July 1, 2020), with respect to the financial statements of Nkarta Therapeutics, Inc. included in the Registration Statement (Form S-1 No. 333-239301) and related Prospectus of Nkarta Therapeutics, Inc. for the registration of shares of its common stock.

/s/ Ernst & Young LLP