Form 8-K

8-K — Keros Therapeutics, Inc.

Accession: 0001664710-26-000053

Filed: 2026-09-08

Period: 2026-09-08

CIK: 0001664710

SIC: 2834 (PHARMACEUTICAL PREPARATIONS)

Item: Other Events

Item: Financial Statements and Exhibits

Documents

8-K — kros-20260908.htm (Primary)

EX-99.1 (exhibit9919826pr.htm)

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8-K

8-K (Primary)

Filename: kros-20260908.htm · Sequence: 1

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0001664710FALSE00016647102026-09-082026-09-08

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): September 8, 2026

Keros Therapeutics, Inc.

(Exact name of registrant as specified in its charter)

Delaware 001-39264 81-1173868

(state or other jurisdiction

of incorporation)

(Commission

File Number)

(I.R.S. Employer

Identification No.)

1050 Waltham Street, Suite 302

Lexington, Massachusetts

02421

(Address of principal executive offices) (Zip Code)

Registrant’s telephone number, including area code: (617) 314-6297

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:

☐ Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐ Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

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

Title of each class

Trading

Symbol

Name of each exchange

on which registered

Common Stock, $0.0001 par value per share KROS The Nasdaq Stock Market LLC

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 8.01 Other Events.

Share Repurchase Program

On September 8, 2026, Keros Therapeutics, Inc., a Delaware corporation (the “Company”), issued a press release announcing that the board of directors of the Company has approved a new stock repurchase program for up to $5 million of the Company’s common stock (the “Stock Repurchase”) following receipt of a $20 million development milestone payment under the license agreement with Takeda Pharmaceuticals U.S.A., Inc. (“Takeda”). A copy of the press release is attached hereto as Exhibit 99.1 and is incorporated herein by reference.

As of June 30, 2026, the Company had cash and cash equivalents of $257.6 million. Based on its current operating plans, the Company anticipates that its cash and cash equivalents as of June 30, 2026, after giving effect to (i) the $20 million development milestone received under the license agreement with Takeda and (ii) the Stock Repurchase, will be sufficient to enable it to fund its operating expenses and capital expenditure requirements into the second half of 2028.

Item 9.01 Financial Statements and Exhibits.

(d) Exhibits

Exhibit

No. Description

99.1

Press Release dated September 8, 2026.

104 Cover Page Interactive Data File (the cover page XBRL tags are embedded within the Inline XBRL document)

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.

KEROS THERAPEUTICS, INC.

By: /s/ Jasbir Seehra

Jasbir Seehra, Ph.D.

Chief Executive Officer

Dated: September 8, 2026

EX-99.1

Filename: exhibit9919826pr.htm · Sequence: 2

Document

Exhibit 99.1

Keros Therapeutics Announces $5 Million Share Repurchase Authorization

LEXINGTON, Mass., September 8, 2026 (GLOBE NEWSWIRE) -- Keros Therapeutics, Inc. (“Keros” or the “Company”) (Nasdaq: KROS), a clinical-stage biopharmaceutical company focused on developing and commercializing novel therapeutics to treat a wide range of patients with disorders that are linked to dysfunctional signaling of the transforming growth factor-beta (“TGF-ß”) family of proteins, today announced that its Board of Directors has approved a $5 million share repurchase program of the Company’s common stock following receipt of a $20 million development milestone payment under the license agreement of elritercept with Takeda Pharmaceuticals U.S.A., Inc., following the dosing of the first patient in the ELRiSE MDS clinical trial. This approval grants Keros’ management the authority to repurchase outstanding shares of the Company’s common stock, from time to time, in the open market and/or by such other means in accordance with applicable state and federal securities laws.

The timing and amount of any repurchases will depend on a variety of factors, including the market price of the Company’s common stock, general market and economic conditions, contractual limitations and other considerations. The program may be modified, suspended or discontinued at any time, and does not obligate the Company to repurchase any dollar amount or number of shares.

About Keros Therapeutics, Inc.

Keros is a clinical-stage biopharmaceutical company focused on developing and commercializing novel therapeutics to treat a wide range of patients with disorders that are linked to dysfunctional signaling of the TGF-ß family of proteins. Keros is a leader in understanding the role of the TGF-ß family of proteins, which are master regulators of the growth, repair and maintenance of a number of tissues, including skeletal muscle, bone, adipose, heart tissue and blood. By leveraging this understanding, Keros has discovered and is developing protein therapeutics that have the potential to provide meaningful and potentially disease-modifying benefit to patients. Keros’ lead product candidate, rinvatercept, is being developed for the treatment of Duchenne muscular dystrophy and for the treatment of amyotrophic lateral sclerosis. Keros’ most advanced product candidate, elritercept, is being developed for the treatment of cytopenias, including anemia and thrombocytopenia, in patients with myelodysplastic syndromes and in patients with myelofibrosis.

Cautionary Note Regarding Forward-Looking Statements

Statements contained in this press release regarding matters that are not historical facts are “forward-looking statements” within the meaning of the Private Securities Litigation Reform Act of 1995, as amended. Words such as “may,” “potential,” “will” or similar expressions are intended to identify forward-looking statements. Examples of these forward-looking statements include statements concerning: the Company’s share repurchase program, including the timing, manner and amount of any repurchases; and Keros’ capital allocation strategy and plans for use of its capital resources. Because such statements are subject to risks and uncertainties, actual results may differ materially from those expressed or implied by such forward-looking statements. These risks and uncertainties include, among others: risks related to the Company’s ability to repurchase shares, including market conditions, stock price fluctuations, and regulatory and contractual constraints; Keros’ limited operating history and historical losses; Keros’ ability to raise additional funding to complete the development and any commercialization of its product candidates; Keros’ dependence on the success of its product candidates, rinvatercept and elritercept; that Keros may be delayed in initiating, enrolling or completing any clinical trials; competition from third parties that are developing products for similar uses; Keros’ ability to obtain, maintain and protect its intellectual property; and Keros’ dependence on third parties in connection with manufacturing, clinical trials and preclinical studies.

These and other risks are described more fully in Keros’ filings with the Securities and Exchange Commission (“SEC”), including the “Risk Factors” section of the Company’s Quarterly Report on Form 10-Q, filed with the SEC on August 3, 2026, and its other documents subsequently filed with or furnished to the SEC. All forward-looking statements contained in this press release speak only as of the date on which they were made. Except to the extent required by law, Keros undertakes no obligation to update such statements to reflect events that occur or circumstances that exist after the date on which they were made.

Investor Contact:

Justin Frantz

jfrantz@kerostx.com

617-221-6042

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