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 5, 2020

DECIPHERA PHARMACEUTICALS, INC.

(Exact name of registrant as specified in its charter)

(781) 209-6400

(Registrant’s telephone number, including area code)

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:

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

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.     ☑

On May 5, 2020, Deciphera Pharmaceuticals, Inc. announced its financial results for the quarter ended March 31, 2020. A copy of the press release in connection with the announcement is being furnished as Exhibit 99.1 to this Current Report on Form 8-K.

The information in this Current Report on Form 8-K (including Exhibit 99.1 attached hereto) is intended to be furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”) or otherwise subject to the liabilities of that section, nor shall it be deemed incorporated by reference in any filing under the Securities Act of 1933, as amended, or the Exchange Act, except as expressly set forth by specific reference in such filing.

(d) Exhibits.

EXHIBIT INDEX

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.

Exhibit 99.1

Deciphera Pharmaceuticals, Inc. Announces First Quarter 2020 Financial Results

- NDA for Ripretinib for the Treatment of Advanced GIST Under Review by U.S. FDA with PDUFA Date of August 13, 2020; Commercial Preparations Underway to Support Potential Launch -

- COVID-19 Business Update Provided; Clinical and Commercial Milestone Timing Affirmed -

- First Quarter 2020 Ended with Cash, Cash Equivalents and Marketable Securities of $691.5 Million; Cash Runway Expected into the Second Half of 2022 -

- Company to Host Conference Call Today at 4:30 PM ET -

Waltham, MA – May 5, 2020 – Deciphera Pharmaceuticals, Inc. (NASDAQ:DCPH) today announced financial results for the first quarter ended March 31, 2020 and provided an update on clinical and corporate developments.

“Work is underway across the company as we prepare for the potential approval and launch of ripretinib later this year,” said Steve Hoerter, President and Chief Executive Officer of Deciphera. “We continue to make progress against our planned 2020 company milestones, including advancing our broad clinical-stage pipeline and completing enrollment in the ongoing, pivotal Phase 3 INTRIGUE study of ripretinib in second-line GIST.”

Mr. Hoerter continued, “In these unprecedented times, we remain steadfast in our mission to bring important new medicines to patients for the treatment of cancer. Our employees have done a tremendous job adapting to the COVID-19 related challenges we are facing as a company, and as an industry, to carry out this mission. We are continuing to actively evaluate the potential impact of the pandemic on our business and proactively explore and implement mitigation measures.”

COVID-19 Business Update

Deciphera is continuously assessing and adapting its business operations in an effort to mitigate interruption from the COVID-19 pandemic on its clinical programs, research efforts and other business activities and to ensure the well-being of its employees, as well as the physicians and patients participating in its clinical studies. At this stage of the COVID-19 pandemic, the operating environment remains fluid and uncertain. The full impact on the Company and its business is not known at this time, and the Company’s outlook assumes the COVID-19 impact on its business will be shorter-term over the next few months and not prolonged.

Clinical Trials and Research and Development Efforts

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Drug Supply

Commercial Activities

Recent Program Highlights

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First Quarter 2020 Financial Results

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Conference Call and Webcast

Deciphera will host a conference call and webcast to discuss this announcement today, May 5, 2020 at 4:30 PM ET. To access the live call by phone please dial (866) 930-5479 (domestic) or (409) 216-0603 (international); the conference ID is 5381739. A live audio webcast of the event may also be accessed through the “Investors” section of Deciphera’s website at www.deciphera.com. A replay of the webcast will be available for 30 days following the event.

About Deciphera Pharmaceuticals

Deciphera Pharmaceuticals is a clinical-stage biopharmaceutical company focused on improving the lives of cancer patients by tackling key mechanisms of drug resistance that limit the rate and/or durability of response to existing cancer therapies. Our small molecule drug candidates are directed against an important family of enzymes called kinases, known to be directly involved in the growth and spread of many cancers. We use our deep understanding of kinase biology together with a proprietary chemistry library to purposefully design compounds that maintain kinases in a “switched off” or inactivated conformation. These investigational therapies comprise tumor-targeted agents designed to address therapeutic resistance-causing mutations and immuno-targeted agents designed to control the activation of immunokinases that suppress critical immune system regulators, such as macrophages. We have used our platform to develop a diverse pipeline of tumor-targeted and immuno-targeted drug candidates designed to improve outcomes for patients with cancer by improving the quality, rate and/or durability of their responses to treatment.

Cautionary Note Regarding Forward-Looking Statements

This press release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, as amended, including, without limitation, our expectations regarding the impact of COVID-19 on our operations, our goals of obtaining FDA approval for and bringing ripretinib to patients with advanced GIST, working with the FDA through its review of our NDA application, preparing for the potential commercial launch of ripretinib in the United States, if approved, including the potential for a virtual launch in light of COVID-19, the progress and potential of our clinical and preclinical development programs for ripretinib, DCC-3014, rebastinib, and DCC-3116, and corporate guidance for 2020, including timing of completion of enrollment in the INTRIGUE Phase 3 study, progress on the pipeline, presentation of updated clinical data, and cash guidance. The words “may,” “will,” “could,” “would,” “should,” “expect,” “plan,” “anticipate,” “intend,” “believe,” “estimate,” “predict,” “project,” “potential,” “continue,” “target” and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words. Any forward-looking statements in this press release are based on management’s current expectations and beliefs and are subject to a number of risks, uncertainties and important factors that may cause actual events or results to differ materially from those expressed or implied by any forward-looking statements contained in this press release, including, without limitation, risks and uncertainties related to the severity and duration of the impact of COVID-19 on the Company’s business and operations, including, without limitation, the progress of our clinical studies and 2020 guidance, commercial and clinical drug supply chain continuity, and the potential commercial launch of ripretinib if approved, our ability to monitor the impact of COVID-19 on our business operations, take mitigation actions to minimize any impact and take steps to ensure the safety of patients and employees, our expectations regarding when COVID-19 impacts may not be as severe, any

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delays and impact of COVID-19 on clinical study sites, patient enrollment, study timelines and data, and regarding drug supply for clinical studies and potential commercialization, the delay of any current or planned clinical studies or the development of our product candidates, including ripretinib, our ability to successfully demonstrate the efficacy and safety of our product candidates including in later-stage studies, the preclinical and clinical results for our product candidates, which may not support further development of such product candidates, our ability to manage our reliance on sole-source third parties such as our third party drug substance and drug product contract manufacturers, actions of regulatory agencies, our ability to plan for potential commercialization of our product candidates, such as ripretinib, and if approved, execute on our marketing plans, the inherent uncertainty in estimates of patient populations and incidence and prevalence estimates, competition from other products, our ability to obtain and maintain reimbursement for any approved product and the extent to which patient assistance programs are utilized, our ability to comply with healthcare regulations and laws, our ability to obtain, maintain and enforce our intellectual property rights, any or all of which may affect the initiation, timing and progress of clinical studies and the timing of and our ability to obtain regulatory approval, if at all, and make our investigational drugs, including ripretinib, available to patients, and, once commercial, to derive revenue from product sales, and other risks identified in our Securities and Exchange Commission (SEC) filings, including our Annual Report on Form 10-K for the year ended December 31, 2019, and subsequent filings with the SEC. We caution you not to place undue reliance on any forward-looking statements, which speak only as of the date they are made. We disclaim any obligation to publicly update or revise any such statements to reflect any change in expectations or in events, conditions or circumstances on which any such statements may be based, or that may affect the likelihood that actual results will differ from those set forth in the forward-looking statements. Any forward-looking statements contained in this press release represent our views only as of the date hereof and should not be relied upon as representing its views as of any subsequent date. We explicitly disclaim any obligation to update any forward-looking statements.

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DECIPHERA PHARMACEUTICALS, INC.

CONSOLIDATED BALANCE SHEETS

(Unaudited, in thousands, except share and per share amounts)

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DECIPHERA PHARMACEUTICALS, INC.

CONSOLIDATED STATEMENTS OF OPERATIONS

(Unaudited, in thousands, except share and per share amounts)

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Contacts:

Investor Relations:

Jen Robinson

Deciphera Pharmaceuticals, Inc

jrobinson@deciphera.com

781-906-1112

Media:

David Rosen

Argot Partners

David.Rosen@argotpartners.com

212-600-1902

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