UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d)

of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): March 30, 2021

Design Therapeutics, Inc.

(Exact name of registrant as specified in its charter)

Registrant’s telephone number, including area code: (858) 293-4900

N/A

(Former name or former address, if changed since last report.)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

Securities registered pursuant to Section 12(b) of the Act:

Indicate by check mark whether the registrant is an emerging growth company as defined in as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company  ☒

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 13(a) of the Exchange Act.  ☒

Amendment and Restatement of Certificate of Incorporation

In connection with the closing of the initial public offering of shares of common stock (the “IPO”) of Design Therapeutics, Inc. (the “Company”) on March 30, 2021, the Company filed an amended and restated certificate of incorporation (the “Restated Certificate”) with the Secretary of State of the State of Delaware. The Board of Directors and stockholders of the Company previously approved the Restated Certificate to be effective as of immediately prior to the closing of the IPO.

Amendment and Restatement of Bylaws

Effective as of March 30, 2021, the Company adopted amended and restated bylaws (the “Restated Bylaws”) in connection with the closing of the IPO. The Board of Directors and stockholders of the Company previously approved the Restated Bylaws to be effective upon the closing of the IPO.

The foregoing descriptions of the Restated Certificate and Restated Bylaws are qualified in their entirety by reference to the full text of the Restated Certificate and Restated Bylaws, which are filed as Exhibits 3.1 and 3.2 hereto, and are incorporated herein by reference.

On March 30, 2021, the Company issued a press release announcing the closing of its IPO of 13,800,000 shares of its common stock, including 1,800,000 shares issued and sold pursuant to the exercise in full by the underwriters of their option to purchase additional shares of common stock, at a price to the public of $20.00 per share. The gross proceeds to the Company were approximately $276.0 million, before deducting underwriting discounts and commissions and offering expenses.

A copy of the Company’s press release announcing the closing of the IPO is attached hereto as Exhibit 99.1 and is incorporated by reference herein.

(d) Exhibits.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

Dated: March 30, 2021