Keros Therapeutics reported $40.01 million revenue for Q3 2026

Item 6. Exhibits

Signature s

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SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS

This Quarterly Report on Form 10-Q contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. All statements other than statements of historical facts contained in this Quarterly Report on Form 10-Q are forward-looking statements, including statements about:

▪ the timing of announcement of data from our ongoing Phase 2 clinical trial of our lead product candidate, rinvatercept (KER-065), in patients with Duchenne muscular dystrophy;

▪ the timing of engagement with regulators on the planned Phase 2 clinical trial of rinvatercept in patients with amyotrophic lateral sclerosis;

▪ plans of Takeda Pharmaceuticals U.S.A., Inc., or Takeda, related to the development of elritercept (KER-050) in patients with myelodysplastic syndromes and in patients with myelofibrosis;

▪ risks associated with public health crises, which may adversely impact our business, nonclinical studies and clinical trials;

▪ our ability to receive the required regulatory approvals and clearances to successfully market and sell our products, if approved in the United States and certain other countries;

▪ our ability to successfully advance our pipeline of additional product candidates;

▪ our ability to develop sales and marketing capabilities;

▪ the rate and degree of market acceptance of any products we are able to commercialize;

▪ the effects of increased competition as well as innovations by new and existing competitors in our market;

▪ our ability to obtain funding for our operations;

▪ the sufficiency of our existing capital resources;

▪ our ability to establish and maintain collaborations;

▪ our ability to effectively manage our anticipated growth;

▪ our ability to maintain, protect and enhance our intellectual property rights and proprietary technologies;

▪ our ability to operate our business without infringing the intellectual property rights and proprietary technology of third parties;

▪ costs associated with defending intellectual property infringement, product liability and other claims;

▪ regulatory developments in the United States, Australia, New Zealand, Georgia, Europe, the United Kingdom and other foreign countries;

▪ our ability to attract and retain qualified employees;

▪ statements regarding future revenue, hiring plans, expenses, capital expenditures, capital requirements and stock performance; and

▪ the future trading prices of our common stock and the impact of securities analysts' reports on these prices.

In some cases, you can identify forward-looking statements by the words "anticipate," "believe," "continue," "could," "estimate," "expect," "intend," "may," "might," "objective," "ongoing," "plan," "predict," "project," "potential," "should," "will," or "would," or the negative of these terms, or other comparable terminology intended to identify statements about the future. These statements involve known and unknown risks, uncertainties and other factors that may cause our actual results, levels of activity, performance or achievements to be materially different from the information expressed or implied by these forward-looking statements.

In addition, statements that "we believe" and similar statements reflect our beliefs and opinions on the relevant subject. These statements are based upon information available to us as of the date of this report, and while we believe such information forms a reasonable basis for such statements, such information may be limited or incomplete, and our statements should not be read to indicate that we have conducted an exhaustive inquiry into, or review of, all potentially available relevant information. These statements are inherently uncertain, and investors are cautioned not to unduly rely upon these statements.

You should read the section titled "Risk Factors" set forth in Part II, Item 1A of this Quarterly Report on Form 10-Q for a discussion of important factors that may cause our actual results to differ materially from those expressed or implied by our forward-looking statements. Moreover, we operate in an evolving environment. New risk factors and uncertainties may emerge

2 from time to time, and it is not possible for management to predict all risk factors and uncertainties. As a result of these factors, we cannot assure you that the forward-looking statements in this Quarterly Report on Form 10-Q will prove to be accurate. Except as required by applicable law, we do not plan to publicly update or revise any forward-looking statements contained herein, whether as a result of any new information, future events, changed circumstances or otherwise.

You should read this Quarterly Report on Form 10-Q completely and with the understanding that our actual future results may be materially different from what we expect. We qualify all of our forward-looking statements by these cautionary statements.

SPECIAL NOTE REGARDING COMPANY REFERENCES

Throughout this Quarterly Report on Form 10-Q, "Keros," the "Company," "we," "us" and "our" refer to Keros Therapeutics, Inc. and its subsidiaries.

SPECIAL NOTE REGARDING TRADEMARKS

All trademarks, trade names and service marks appearing in this Quarterly Report on Form 10-Q are the property of their respective owners.

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SUMMARY OF SELECTED RISKS ASSOCIATED WITH OUR BUSINESS

Our business faces significant risks and uncertainties. If any of the following risks are realized, our business, financial condition and results of operations could be materially and adversely affected. You should carefully review and consider the full discussion of our risk factors in the section titled "Risk Factors" in Part II, Item 1A of this Quarterly Report on Form 10-Q. Some of the more significant risks include the following:

• We have a limited operating history, have incurred net losses in almost every year since our inception and anticipate that we will continue to incur net losses in the future.

• We will need subs

Item 1. FINANCIAL STATEMENTS (unaudited)

KEROS THERAPEUTICS, INC.

Condensed Consolidated Balance Sheets

(In thousands, except share and per share data)

(Unaudited)

SEPTEMBER 30, 2026 DECEMBER 31,

2025

ASSETS

CURRENT ASSETS:

Prepaid expenses and other current assets 5,920 22,202

Operating lease right-of-use assets 14,887 16,841

Other long-term assets 11 —

TOTAL ASSETS $ 307,371² $ 338,021 LIABILITIES AND STOCKHOLDERS' EQUITY CURRENT LIABILITIES:

Accounts payable $ 3,787 $ 1,967

Current portion of operating lease liabilities 2,695 2,408

Accrued expenses and other current liabilities 8,761 16,039

Current tax liability 615 —

Total current liabilities 15,858 20,414

Operating lease liabilities, net of current portion 12,415 14,475

— —

Series A junior participating preferred stock, par value of $ 0.0001 per share; 500,000 shares authorized as of September 30, 2026 and December 31, 2025; no shares issued and outstanding

— —

TOTAL LIABILITIES AND STOCKHOLDERS' EQUITY

$ 307,371 $ 338,021

See notes to condensed consolidated financial statements.

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KEROS THERAPEUTICS, INC.

Condensed Consolidated Statements of Operations

(In thousands, except share and per share data)

(Unaudited)

THREE MONTHS ENDED SEPTEMBER 30, NINE MONTHS ENDED SEPTEMBER 30,

See notes to condensed consolidated financial statements.

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KEROS THERAPEUTICS, INC.

Condensed Consolidated Statements of Stockholders' Equity

(In thousands, except share and per share data)

(Unaudited)

COMMON STOCK $ 0.0001 PAR VALUE TREASURY STOCK ADDITIONAL PAID-IN

CAPITAL ACCUMULATED DEFICIT TOTAL STOCKHOLDERS' EQUITY SHARES AMOUNT SHARES AMOUNT

Vesting of restricted stock 173,827 — — — — — —

Vesting of restricted stock 27,351 — — — — — —

Vesting of restricted stock 138,113 — — — — — —

Repurchase of treasury stock, including commissions of $ 3 thousand

COMMON STOCK $ 0.0001 PAR VALUE TREASURY STOCK ADDITIONAL PAID-IN

CAPITAL ACCUMULATED DEFICIT TOTAL STOCKHOLDERS' EQUITY SHARES AMOUNT SHARES AMOUNT

Stock-bas