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): May 20, 2021

Assembly Biosciences, Inc.

(Exact name of Registrant as Specified in Its Charter)

Registrant’s Telephone Number, Including Area Code: (833) 509-4583

Not Applicable

(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 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. ☐

Item 5.02 Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers.

Amendment No. 4. to 2018 Stock Incentive Plan

At the Assembly Biosciences, Inc. (the “Company”) Annual Meeting of Stockholders held on May 20, 2021 (the “Annual Meeting”), the Company’s stockholders approved Amendment No. 4 (the “Amendment”) to the Assembly Biosciences, Inc. Stock Incentive Plan (the “2018 Plan”) to increase the number of shares reserved for issuance thereunder from 4,600,000 shares of common stock to 6,600,000 shares. A copy of the Amendment is attached as Exhibit 10.1 and is incorporated herein by reference.

A summary of the material terms of the 2018 Plan, as amended by the Amendment, is set forth as a part of Proposal 4 in the Company’s definitive proxy statement on Schedule 14A filed with the Securities and Exchange Commission on April 7, 2021 (the “Proxy Statement”) and is incorporated by reference herein. That summary is qualified in its entirety by reference to the full text of the 2018 Plan incorporating the Amendment, set forth as Appendix B of the Proxy Statement, which is also incorporated by reference herein.

Amended and Restated 2018 Employee Stock Purchase Plan

At the Annual Meeting, the Company’s stockholders approved the Assembly Biosciences, Inc. Amended and Restated 2018 Employee Stock Purchase Plan (the “Amended and Restated 2018 ESPP”). The Amended and Restated 2018 ESPP increased (1) the aggregate number of shares of the Company’s common stock reserved for issuance thereunder from 400,000 shares to 1,300,000 shares and (2) the maximum number of shares purchasable from 1,000 shares per offering period to 2,500 shares per offering period.

A summary of the material terms and conditions of the Amended and Restated 2018 ESPP is set forth in the Proxy Statement and is incorporated herein by reference. That summary is qualified in its entirety by reference to the full text of the Amended and Restated 2018 ESPP, which is attached hereto as Exhibit 10.2 and is incorporated herein by reference.

Item 5.07 Submission of Matters to a Vote of Security Holders.

On May 20, 2021, the matters listed below were submitted to a vote of the Company’s stockholders at the Annual Meeting through the solicitation of proxies. Detailed descriptions of each of the proposals are included in the Proxy Statement. The results of the stockholders’ votes are as follows:

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Item 9.01 Financial Statements and Exhibits.

(d) Exhibits.

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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 thereunto duly authorized.

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