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EX-99.1

2 exhibit991q12026.htm

EX-99.1

Document

Exhibit 99.1

Keros Therapeutics Reports Recent First Quarter 2026 Financial Results

LEXINGTON, Mass., May 14, 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 reported financial results for the quarter ended March 31, 2026.

“Continuing to progress our pipeline remains our top priority, setting the stage for future catalysts and growth opportunities,” said Jasbir S. Seehra, Ph.D., President and Chief Executive Officer. “In addition, we are excited that our partner, Takeda Pharmaceuticals U.S.A., Inc. (“Takeda”), plans to advance elritercept into a Phase 3 clinical trial to evaluate elritercept as a treatment of anemia in myelofibrosis, broadening the indication opportunity beyond myelodysplastic syndromes.”

First Quarter 2026 Financial Results

Keros reported a net loss of $23.7 million in the first quarter of 2026 as compared to a net income of $148.5 million in the first quarter of 2025. The decrease of $172.2 million was largely due to revenue recognized in 2025 related to Keros' license agreement with Takeda and decreased research and development efforts.

Research and development expenses were $16.1 million for the first quarter of 2026 as compared to $48.7 million for the same period in 2025. The decrease of $32.6 million was primarily due to the transition of elritercept-related research and development expenses to Takeda and the corporate restructuring that was completed in 2025.

General and administrative expenses were $10.1 million for the first quarter of 2026 as compared to $10.5 million for the same period in 2025. The decrease of $0.4 million was primarily due to a decrease in compensation costs in connection with the 2025 corporate restructuring.

Keros’ cash and cash equivalents as of March 31, 2026 was $281.5 million compared to $287.4 million as of December 31, 2025. Based on current operating assumptions, Keros expects that its cash and cash equivalents as of March 31, 2026 will enable Keros to fund its operating expenses and capital expenditure requirements into the first half of 2028.

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 syndrome 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 “continue”, “expect”, “plan”, “look forward to”, “will”, “potential” or similar

expressions are intended to identify forward-looking statements. Examples of these forward-looking statements include statements concerning: Keros’ expectations regarding its growth, strategy, progress and the design, objectives and timing of its clinical trials for rinvatercept and elritercept; Takeda’s plans to advance elritercept into a Phase 3 clinical trial to evaluate elritercept as a treatment of anemia in myelofibrosis; and Keros’ expected cash runway. 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: 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

kros-202603040001664710FALSE00016647102026-03-042026-03-040001664710us-gaap:CommonStockMember2026-03-042026-03-040001664710us-gaap:PreferredStockMember2026-03-042026-03-04

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): March 4, 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 Preferred Share Purchase RightsN/AThe 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 2.02    Results of Operations and Financial Condition.

On March 4, 2026, Keros Therapeutics, Inc. (the “Company”) issued a press release announcing its recent business highlights and financial results for the quarter and year ended December 31, 2025. A copy of the press release is furnished hereto as Exhibit 99.1 and is incorporated herein by reference. The information in this Item 2.02, including Exhibit 99.1 attached hereto, is being 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. The information contained in this Item 2.02 and in the accompanying exhibit is not incorporated by reference in any filing of the Company under the Securities Act of 1933, as amended (the “Securities Act”), or the Exchange Act, whether made before or after the date hereof, regardless of any general incorporation language in such filing, except as shall be expressly set forth by specific reference in such filing. Item 9.01     Financial Statements and Exhibits.

(d) Exhibits

Exhibit No. Description 99.1 Press Release dated March 4, 2026.

104Cover 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: March 4, 2026