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 13, 2021

Silverback Therapeutics, Inc.

(Exact name of registrant as specified in its charter)

Registrant’s telephone number, including area code: (206) 456-2900

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.  ☐

On May 13, 2021, Silverback Therapeutics, Inc. (the “Company”) issued a press release announcing its financial results for the three months ended March 31, 2021. A copy of the press release is attached hereto as Exhibit 99.1.

The information in this Item and the exhibit attached hereto are being furnished and shall not be deemed “filed” for the 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 they be deemed incorporated by reference into any filing under the Exchange Act or the Securities Act of 1933, as amended, whether filed before or after the date hereof and regardless of any general incorporation language in such filing.

(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: May 13, 2021

Exhibit 99.1

Silverback Therapeutics Reports First Quarter 2021 Financial Results

SEATTLE – May 13, 2021 – Silverback Therapeutics, Inc. (Nasdaq: SBTX) (“Silverback”), a clinical-stage biopharmaceutical company leveraging its proprietary ImmunoTAC technology platform to develop systemically delivered, tissue targeted therapeutics for the treatment of cancer, chronic viral infections, and other serious diseases, today reported financial results for the first quarter ended March 31, 2021 and provided a business update.

“In our first quarter as a public company, our team continues to execute on Silverback’s mission to bring tissue-targeted therapies to patients in need,” said Laura Shawver, Ph.D., chief executive officer of Silverback. “We are on track to report interim clinical data for SBT6050 in the second half of this year, and we are equally excited about the progress and preclinical data emerging from SBT6290 and SBT8230, highlighting the broad applicability of our ImmunoTAC platform.”

Recent Highlights

First Quarter Financial Results

For the first quarter ended March 31, 2021, Silverback reported a net loss of $18.9 million, compared to a net loss of $5.3 million for the comparable period in 2020. Net loss for the first quarter of 2021 included non-cash stock-based compensation expense of $4.3 million compared to $47,000 for the same period in 2020.

Research and development expenses for the first quarter ended March 31, 2021 were $12.2 million, compared to $4.4 million for the same period in 2020. The increases in the Company’s research and development expenses in 2021 were primarily attributable to the advancement of pipeline programs, including SBT6290 and SBT8230, into preclinical development and the continued development of SBT6050. Silverback also incurred additional personnel-related expenses as operations grew in support of program advances.

General and administrative expenses for the first quarter ended March 31, 2021 were $6.6 million, compared to $0.8 million for the same period in 2020. The increases in general and administrative expenses were primarily attributable to an increase in personnel-related expenses due to increased headcount in 2020, including new executives, as well as increases in salaries, bonuses, and stock-based compensation. The increases in general and administrative expenses were also due to an increase in legal fees, professional fees, and other various general and administrative expenses as we now operate as a public company.

As of March 31, 2021, Silverback reported cash and cash equivalents of $374.2 million, compared to $386.6 million at December 31, 2020, which is expected to fund operating expenses and capital expenditure requirements for at least the next 24 months.

About Silverback Therapeutics

Silverback Therapeutics, Inc. is a clinical-stage biopharmaceutical company focused on leveraging its proprietary ImmunoTAC technology platform to develop systemically delivered and tissue targeted therapeutics for the treatment of cancer, chronic viral infections, and other serious diseases. Silverback’s platform enables the strategic pairing of proprietary payloads that modulate key disease modifying pathways with monoclonal antibodies directed at specific disease sites. Initially, Silverback is creating a new class of targeted immuno-oncology agents that direct a TLR8 agonist myeloid cell activator to the tumor microenvironment in solid tumors to promote cancer cell killing. Silverback Therapeutics is located in Seattle, Washington. To learn more, visit www.silverbacktx.com.

Forward-Looking Statements

This news release contains certain forward-looking statements that involve risks and uncertainties that could cause actual results to be materially different from historical results or from any future results expressed or implied by such forward-looking statements. Such forward-looking statements include statements regarding our intentions, beliefs, projections, outlook, analyses or current expectations concerning, among other things, Silverback’s plans and ability to bring new treatments to patients in need, the progress and expected timing of Silverback’s drug development programs and clinical trials, the strength of Silverback’s balance sheet and the adequacy of cash on hand. Factors that may cause actual results to differ materially include the risk that compounds that appeared promising in early research or clinical trials do not demonstrate safety and/or efficacy in later preclinical studies or clinical trials, the risk that Silverback may not obtain approval to market its product candidates, uncertainties associated with performing clinical trials, regulatory filings and applications, risks associated with reliance on third parties to successfully conduct clinical trials, risks associated with the impact of the COVID-19 pandemic on our business and the global economy, the risks associated with reliance on outside financing to meet capital requirements, the risks associated with losing key members of management and other risks associated with the process of discovering, developing and commercializing drugs that are safe and effective for use as human therapeutics, and in the endeavor of building a business around such drugs. You are urged to consider statements that include the words “may,” “will,” “would,” “could,” “should,” “believes,” “estimates,” “projects,” “promise,” “potential,” “expects,” “plans,” “anticipates,” “intends,” “continues,” “designed,” “goal,” or the negative of those words or other comparable words to be uncertain and forward-looking. For a further list and description of the risks and uncertainties that Silverback faces, please refer to Silverback’s periodic and other filings with the Securities and Exchange Commission, which are available at www.sec.gov. Such forward-looking statements are current only as of the date they are made, and Silverback assumes no obligation to update any forward-looking statements, whether as a result of new information, future events or otherwise.

Investor Contact:

Miguel Arcinas

Silverback Therapeutics

(206) 736-7946

ir@silverbacktx.com

Media Contact:

Jason Spark

Canale Communications

(619) 849-6005

jason.spark@canalecomm.com

Silverback Therapeutics, Inc.

Condensed Balance Sheets

(in thousands, except share and par value data)

Silverback Therapeutics, Inc.

Condensed Statements of Operations and Comprehensive Loss

(in thousands, except share and per share data)

(unaudited)