As filed with the Securities and Exchange Commission on March 9, 2020

Registration No. 333-            

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM S-8

REGISTRATION STATEMENT

Under

The Securities Act of 1933

DECIPHERA PHARMACEUTICALS, INC.

(Exact name of registrant as specified in its charter)

200 Smith Street

Waltham, MA 02451

(781) 209-6400

(Address of Principal Executive Offices)

Deciphera Pharmaceuticals, Inc. 2017 Stock Option and Incentive Plan

Deciphera Pharmaceuticals, Inc. 2017 Employee Stock Purchase Plan

(Full Title of the Plans)

Steven L. Hoerter

President & Chief Executive Officer

Deciphera Pharmaceuticals, Inc.

200 Smith Street

Waltham, MA 02451

(781) 209-6400

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

Copies to:

Richard A. Hoffman, Esq.

Sarah Ashfaq, Esq.

Goodwin Procter LLP

100 Northern Avenue

Boston, MA 02210

(617) 570-1000

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 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.  ☒

CALCULATION OF REGISTRATION FEE

EXPLANATORY NOTE

This Registration Statement on Form S-8 registers additional shares of Common Stock under the Registrant’s 2017 Stock Option and Incentive Plan (the “Plan”) and the Registrant’s 2017 Employee Stock Purchase Plan (the “ESPP”). The number of shares of Common Stock reserved and available for issuance under the Plan is subject to an automatic annual increase on each January 1, beginning in 2018, by an amount equal to four percent of the number of shares of Common Stock issued and outstanding on the immediately preceding December 31 or such lesser number of shares of Common Stock as determined by the Administrator (as defined in the Plan). Accordingly, on January 1, 2020, the number of shares of Common Stock reserved and available for issuance under the Plan increased by 2,064,706 shares. The number of shares of Common Stock reserved and available for issuance under the ESPP is subject to an automatic annual increase on each January 1, beginning in 2018, by the lesser of 400,000 shares, one percent of the number of shares of Common Stock issued and outstanding on the immediately preceding December 31 or such lesser number of shares of Common Stock as determined by the Administrator (as defined in the ESPP). Accordingly, on January 1, 2020, the number of shares of Common Stock reserved and available for issuance under the ESPP increased by 400,000 shares. This Registration Statement registers these additional 2,464,706 shares of Common Stock. The additional shares are of the same class as other securities relating to the Plans for which the Registrant’s Registration Statement filed on Form S-8 (Registration No.  333-220866) on October 6, 2017 is effective. The information contained in the Registrant’s registration statement on Form S-8 (Registration No. 333-220866) is hereby incorporated by reference pursuant to General Instruction E.

Part II

INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

See the Exhibit Index on the page immediately preceding the exhibits for a list of exhibits filed as part of this Registration Statement, which Exhibit Index is incorporated herein by reference.

EXHIBIT INDEX

SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, the Registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-8 and has duly caused this Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Waltham, Commonwealth of Massachusetts, on the 9^th day of March, 2020.

POWER OF ATTORNEY AND SIGNATURES

KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature appears below constitutes and appoints Steven L. Hoerter and Thomas P. Kelly his or her true and lawful attorney-in-fact and agent with full power of substitution, for him or her and in his or her name, place and stead, in any and all capacities, to sign any and all amendments (including post-effective amendments) to this Registration Statement on Form S-8, and to file the same, with all exhibits thereto and all documents in connection therewith, with the Securities and Exchange Commission, granting unto said attorney-in-fact and agent, full power and authority to do and perform each and every act and thing requisite and necessary to be done in and about the premises, as fully to all intents and purposes as he or she might or could do in person, hereby ratifying and confirming that all said attorneys-in-fact and agents or any of them, or his, her or their substitute or substitutes, may lawfully do or cause to be done by virtue hereof.

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 date indicated.

Exhibit 5.1

March 9, 2020

Deciphera Pharmaceuticals, Inc.

200 Smith Street

Waltham, MA 02451

We have acted as counsel to you in connection with your filing of a Registration Statement on Form S-8 (the “Registration Statement”) pursuant to the Securities Act of 1933, as amended (the “Securities Act”), on or about the date hereof relating to an aggregate of 2,464,706 shares (the “Shares”) of Common Stock, $0.01 par value per share (“Common Stock”), of Deciphera Pharmaceuticals, Inc., a Delaware corporation (the “Company”), that may be issued pursuant to the Company’s 2017 Stock Option and Incentive Plan and 2017 Employee Stock Purchase Plan (collectively, the “Plans”).

We have reviewed such documents and made such examination of law as we have deemed appropriate to give the opinions set forth below. We have relied, without independent verification, on certificates of public officials and, as to matters of fact material to the opinion set forth below, on certificates of officers of the Company.

The opinion set forth below is limited to the Delaware General Corporation Law.

For purposes of the opinion set forth below, we have assumed that no event occurs that causes the number of authorized shares of Common Stock available for issuance by the Company to be less than the number of then unissued Shares.

Based on the foregoing, we are of the opinion that the Shares have been duly authorized and, upon issuance and delivery against payment therefor in accordance with the terms of the Plans, will be validly issued, fully paid and nonassessable.

We hereby consent to the inclusion of this opinion as Exhibit 5.1 to the Registration Statement. In giving our consent, we do not admit that we are in the category of persons whose consent is required under Section 7 of the Securities Act or the rules and regulations thereunder.

Exhibit 23.1

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

We hereby consent to the incorporation by reference in this Registration Statement on Form S-8 of Deciphera Pharmaceuticals, Inc. of our report dated March 9, 2020 relating to the financial statements, which appears in Deciphera Pharmaceuticals, Inc.’s Annual Report on Form 10-K for the year ended December 31, 2019.