omer20251014

omer20251014_8k.htm

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): October 10, 2025

OMEROS CORPORATION

(Exact name of Registrant as Specified in Its Charter)

Washington	001-34475	91-1663741
(State or Other Jurisdiction of Incorporation)	(Commission File Number)	(IRS Employer Identification No.)

201 Elliott Avenue West

Seattle, WA 98119

(Address of Principal Executive Offices and Zip Code)

Registrant’s Telephone Number, Including Area Code: (206) 676-5000

(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 (see General Instruction A.2. below):

☐	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(s)	Name of each exchange on which registered
Common stock, par value $0.01 per share	OMER	The Nasdaq Stock Market LLC

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 under the Securities Act of 1933 (17 CFR 230.405) or Rule 12b-2 under the Securities Exchange Act of 1934 (17 CFR 240.12b-2).

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 1.01

Entry into a Material Definitive Agreement.

Asset Purchase and License Agreement

On October 10, 2025, Omeros Corporation (the “Company”) entered into an Asset Purchase and License Agreement (the “Agreement”) with Novo Nordisk Health Care AG (“Novo Nordisk”), pursuant to which Novo Nordisk will receive exclusive global rights in all indications to develop and commercialize zaltenibart (OMS906), the Company’s lead human monoclonal antibody targeting mannan-binding lectin-associated serine protease-3 (“MASP-3”), certain related monoclonal antibodies and antigen-binding fragments (collectively, the “Compounds”), and related pharmaceutical products (“Products”). Under the Agreement, the Company agreed to sell and transfer, and Novo Nordisk agreed to purchase and assume, certain assets and liabilities related to the Compounds and Products, and the parties agreed to grant and receive certain intellectual property licenses, as further described below (the “Transaction”).

Pursuant to the terms and subject to the conditions of the Agreement, Omeros is eligible to receive up to $2.1 billion in upfront and milestone-based payments. This includes an upfront cash payment of $240.0 million to be received by the Company at the closing of the Transaction (the “Closing”). In addition, Omeros can receive (i) up to a total of $510 million in one-time milestone payments upon the first achievement by Novo Nordisk or its affiliates or sublicensees of each of the development and approval milestone events as set forth in the Agreement and (ii) up to $1.3 billion in one-time milestone payments upon the first achievement by Novo Nordisk or its affiliates or sublicensees of certain sales-based milestone events as set forth in the Agreement. The Company is also eligible under the Agreement to receive tiered royalties on annual net sales of Products at percentage rates ranging from high single digit to high teens, subject to reduction in certain circumstances, as set forth in the Agreement.

Exclusivity and Retained Rights

During the term of the Agreement, the Company and its respective affiliates will be restricted from exploiting products directed to MASP-3 and certain other alternative pathway targets, subject to certain exceptions for retained preclinical program rights (outside of zaltenibart), products of an acquirer, and non-competing indications. The Company retains rights to continue development of its existing MASP-3 small-molecule program, including the ability to develop and commercialize small-molecule inhibitors with limited indication restrictions. The Company also retains rights to its “grandfathered” MASP-3 antibodies, with temporal and indication restrictions on commercialization and for use in advancing its small-molecule therapeutics.

Closing and Termination Rights.

The Closing is subject to the satisfaction or waiver of certain customary closing conditions, including (i) the absence of any law, order, or governmental proceeding that prohibits or makes illegal the consummation of the Transaction, (ii) the expiration or termination of the applicable waiting period under the Hart-Scott-Rodino Antitrust Improvements Act of 1976, as amended, (iii) the accuracy of each party’s representations and warranties contained in the Agreement (subject to customary materiality and other qualifiers), (iv) each party’s performance and compliance with its covenants contained in the Agreement, (v) the absence of a material adverse effect, and (vi) delivery of certain closing deliverables.

Either the Company or Novo Nordisk may terminate the Agreement if (i) the Closing has not occurred before a certain date, (ii) any final and non-appealable order, decree, or injunction has been issued by a governmental entity that makes illegal or restrains or enjoins the Transaction, or (iii) the other party is in material breach under the Agreement such that certain conditions to the Closing would not be satisfied and such material breach is not cured within the time period specified in the Agreement. The Agreement may also be terminated by the mutual written consent of the Company and Novo Nordisk.

Subject to the satisfaction or waiver of the foregoing conditions and the other terms and conditions contained in the Agreement, the Transaction is expected to close in the fourth quarter of 2025.

Other Terms

The Agreement contains other customary terms and conditions, including representations, warranties, and covenants of the parties, including, among others, covenants by the Company regarding the conduct of the Company prior to the Closing. The Agreement also includes customary indemnification obligations of both parties.

The Agreement also contemplates that, at the Closing, the Company and Novo Nordisk will enter into a transition services agreement (the “Transition Services Agreement”), pursuant to which the Company will provide certain transition services to Novo Nordisk to facilitate the transfer of the acquired assets and liabilities under the Agreement and to provide for the continued operation of relevant studies and program activities during the applicable term. Subject to certain exceptions and limitations, Novo Nordisk will reimburse the Company for costs and expenses incurred by the Company under the Transition Services Agreement, including third-party costs and expenses and costs associated with delivery by Omeros of transition services on an hourly basis at rates specified in the Agreement.

The foregoing is a brief description of the material terms of the Agreement and does not purport to be a complete description of the rights and obligations of the parties thereunder. A copy of the Agreement will be filed as an exhibit to a future periodic or current report. The Agreement contains representations, warranties, and covenants that were made for the purpose of allocating contractual risk between those parties, that do not establish these matters as facts and, in certain cases, are subject to separately scheduled exceptions and qualifications. Investors should not rely on the representations, warranties, and covenants as characterizations of the actual state of facts or condition of the Company, Novo Nordisk, or any of their respective subsidiaries or affiliates.

Repayment of Credit Agreement at Closing

At Closing of the Transaction, a portion of the $240.0 million upfront payment will be applied to the repayment of all outstanding obligations under that certain Credit and Guarantee Agreement, dated June 3, 2024 (the “Credit Agreement”), among the Company, the various lenders party thereto, and Wilmington Savings Fund Society, FSB, as Administrative Agent and Collateral Agent. The retirement will relate to the $67.1 million outstanding term loan under the Credit Agreement, along with related prepayment premiums and accrued and unpaid interest. Repayment of our obligations under the Credit Agreement will result in the release in full of all liens and covenants thereunder.

Item 8.01

Other Events.

On October 15, 2025, the Company issued a press release announcing the Transaction. A copy of the press release is attached as Exhibit 99.1 to this Current Form 8-K and is incorporated by reference herein.

This Current Report on Form 8-K contains forward-looking statements within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934, which are subject to the “safe harbor” created by those sections for such statements. All statements other than statements of historical fact are forward-looking statements, which are often indicated by terms such as “anticipate,” “believe,” “could,” “estimate,” “expect,” “goal,” “intend,” “likely,” “look forward to,” “may,” “objective,” “plan,” “potential,” “predict,” “project,” “should,” “slate,” “target,” “will,” “would” and similar expressions and variations thereof. Forward-looking statements, including statements regarding the Company’s expectations with regard to completion of, and payments to be received from, the Transaction, are based on management’s beliefs and assumptions and on information available to management only as of the date hereof. The Company’s actual results could differ materially from those anticipated in these forward-looking statements for many reasons, including, without limitation, risks associated with product commercialization and commercial operations, regulatory processes and oversight, and the risks, uncertainties and other factors described under the heading “Risk Factors” in the Company’s Annual Report on Form 10-K filed with the Securities and Exchange Commission on March 30, 2025, as amended on April 30, 2025. Given these risks, uncertainties and other factors, you should not place undue reliance on these forward-looking statements, and the Company assumes no obligation to update these forward-looking statements, whether as a result of new information, future events or otherwise, except as required by applicable law.

Item 9.01

Financial Statements and Exhibits.

(d) Exhibits.

Exhibit Number		Description
99.1		Press Release, dated October 15, 2025.
104		Cover Page Interactive Data File (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.

	OMEROS CORPORATION

Date: October 15, 2025	By:	/s/ Gregory A. Demopulos
		Gregory A. Demopulos, M.D.
		President, Chief Executive Officer and
		Chairman of the Board of Directors

Exhibit 99.1

Novo Nordisk and Omeros announce asset purchase and license agreement for Omeros’ clinical-stage MASP-3 inhibitor zaltenibart (OMS906)

● Zaltenibart has best-in-class potential across multiple rare blood and kidney disorders and will enhance Novo Nordisk’s Rare Disease portfolio

● Omeros is eligible to receive 340 million US dollars in upfront and near-term milestone payments, up to a total of 2.1 billion dollars including potential development and commercial milestones, plus tiered royalties on net sales

Bagsværd, Denmark and Seattle, US, 15 October 2025 – Novo Nordisk and Omeros Corporation (Nasdaq: OMER) today announced that they have entered into a definitive asset purchase and license agreement for the candidate drug zaltenibart (formerly OMS906) in clinical development for rare blood and kidney disorders.

Under the terms of the agreement, Novo Nordisk will be granted exclusive global rights to develop and commercialise zaltenibart in all indications. Omeros is eligible to receive 340 million US dollars in upfront and near-term milestone payments, up to a total of 2.1 billion dollars including potential development and commercial milestones, plus tiered royalties on net sales.

Zaltenibart is an antibody designed to inhibit MASP-3, a protein that acts as a key activator of the complement system’s alternative pathway. Dysregulation of the complement system, a crucial part of the immune system, has been shown to be involved in the pathophysiology of a number of rare diseases.

“Zaltenibart has a novel mode of action that could offer several advantages over other treatments for complement-mediated diseases,” said Martin Holst Lange, chief scientific officer and executive vice president of Research & Development at Novo Nordisk. “Novo Nordisk is in a strong position to build on the work done by Omeros to maximise the value of this asset and develop zaltenibart into a differentiated and potentially best-in-class treatment approach for a number of rare blood and kidney disorders.”

Omeros has reported positive phase 2 data for zaltenibart in paroxysmal nocturnal hemoglobinuria (PNH) - a rare, acquired blood disorder where the body's immune system mistakenly attacks and destroys red blood cells, leading to low levels of healthy red blood cells and other complications. Zaltenibart has shown multiple potential advantages over other alternative pathway inhibitors in development or on the market, and it has been well tolerated and demonstrated an acceptable safety profile across all clinical trials to date.

“We are pleased to enter into this agreement with Novo Nordisk, a global leader in therapeutic innovation and development,” said Gregory A. Demopulos, M.D., Chairman and Chief Executive Officer of Omeros. “We look forward to Novo Nordisk levering its extensive expertise and global reach to unlock the potential of zaltenibart across alternative pathway indications. With Novo Nordisk driving the success of zaltenibart, Omeros remains focused on securing approval and commercialisation of narsoplimab this quarter and continuing to advance its robust development pipeline.”

Omeros retains certain rights to its preclinical MASP-3 programmes unrelated to zaltenibart, including the ability to develop and commercialise small-molecule MASP-3 inhibitors with limited indication restrictions.

Following closing of the transaction, Novo Nordisk aims to initiate a global phase 3 programme for zaltenibart in PNH and explore further development in a range of other rare blood and kidney disorders.

“With zaltenibart, we have a compelling opportunity to help a significant number of people living with rare blood and kidney disorders in the future and support our leadership ambition in this space,” said Ludovic Helfgott, executive vice president of Product and Portfolio Strategy at Novo Nordisk. “This agreement will build on Novo Nordisk’s heritage and enhance our existing Rare Disease portfolio with potential to drive additional growth in this business area.”

The transaction is subject to certain customary closing conditions, including applicable regulatory approvals, and is expected to close in the fourth quarter of 2025.

About zaltenibart

Zaltenibart (OMS906) is an investigational humanized monoclonal antibody that selectively targets mannan-binding lectin-associated serine protease-3 (MASP-3), the key and most upstream activator of the alternative pathway of the complement system and a critical component of innate immunity involved in host defense and immune regulation.

MASP-3 is responsible for converting complement pro-factor D to its active form, factor D. With a low systemic circulation compared to other alternative pathway proteins and slow circulation clearance, MASP-3 is considered a highly attractive therapeutic target. Unlike inhibitors of C3 or C5, MASP-3 inhibition preserves the classical pathway function, which is critical to vaccine-induced immunity and defense against infections. Moreover, MASP-3 is not believed to be an acute-phase reactant, potentially offering another significant advantage for MASP-3 inhibitors like zaltenibart.

Zaltenibart has potential applications across a broad range of therapeutic areas and indications, including paroxysmal nocturnal hemoglobinuria (PNH), renal diseases such as immunoglobulin A nephropathy (IgAN), C3 glomerulopathy and atypical hemolytic uremic syndrome, and other immune and complement driven-disorders.

About Omeros Corporation

Omeros is a clinical-stage biopharmaceutical company focused on discovering, developing, and commercializing first-in-class small-molecule and protein therapeutics for large-market and orphan indications, with a particular emphasis on complement-mediated diseases, cancers, and addictive or compulsive disorders. Omeros’ lead MASP-2 inhibitor narsoplimab targets the lectin pathway of complement and is under regulatory review by both the U.S. FDA and the European Medicines Agency for the treatment of hematopoietic stem cell transplant-associated thrombotic microangiopathy. OMS1029, a long-acting MASP-2 inhibitor, has successfully completed Phase 1 clinical trials. Zaltenibart (OMS906), Omeros’ MASP-3 inhibitor, is in clinical development for PNH and C3 glomerulopathy. Under a recently announced agreement, Novo Nordisk will acquire global rights to zaltenibart, including associated intellectual property and related assets. Omeros’ pipeline also includes OMS527, a phosphodiesterase 7 inhibitor in clinical development for cocaine use disorder, fully funded by the National Institute on Drug Abuse, as well as a growing portfolio of novel molecular and cellular therapeutic programs for oncology. For more information visit www.omeros.com.

About Novo Nordisk

Novo Nordisk is a leading global healthcare company, founded in 1923 and headquartered in Denmark. Our purpose is to drive change to defeat serious chronic diseases, built upon our heritage in diabetes. We do so by pioneering scientific breakthroughs, expanding access to our medicines, and working to prevent and ultimately cure disease. As of August 2025, Novo Nordisk employed about 78,400 people in 80 countries and markets its products in around 170 countries. For more information, visit novonordisk.com, Facebook, X, LinkedIn and YouTube.

Contacts for further information

Novo Nordisk Media:
Ambre James-Brown +45 3079 9289 [email protected],	Liz Skrbkova (US) +1 609 917 0632 [email protected]

Novo Nordisk investors:
Jacob Martin Wiborg Rode +45 3075 5956 [email protected]	Sina Meyer +45 3079 6656 [email protected]

Max Ung +45 3077 6414 [email protected]	Christoffer Sho Togo Tullin +45 3079 1471 [email protected]

Alex Bruce +45 3444 2613 [email protected]	Frederik Taylor Pitter +1 609 613 0568 [email protected]

Omeros Investors and Media: Jennifer Cook Williams Cook Williams Communications, Inc. [email protected]

Omeros Corporation Cautionary Note on Forward-Looking Statements

This press release contains forward-looking statements within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934, which are subject to the “safe harbor” created by those sections for such statements. All statements other than statements of historical fact are forward-looking statements, which are often indicated by terms such as “anticipate,” “believe,” “could,” “estimate,” “expect,” “goal,” “intend,” “likely,” “look forward to,” “may,” “objective,” “plan,” “potential,” “predict,” “project,” “should,” “slate,” “target,” “will,” “would,” and similar expressions and variations thereof. Forward-looking statements, including statements regarding the anticipated closing of the transactions contemplated by the Agreement, plans for development of zaltenibart or other products under the Agreement, the potential therapeutic benefits of zaltenibart and its commercial prospects, and expectations regarding Omeros’ other programs and operations, including statements regarding commercialization of its product candidates are based on management’s beliefs and assumptions and on information available to management only as of the date of this press release. Omeros’ actual results could differ materially from those anticipated in these forward-looking statements for many reasons, including, without limitation, unfavorable or unexpected regulatory conclusions or interpretations related to the clinical data, external registry data, statistical analyses or other information and data, unanticipated or unexpected outcomes or requirements of regulatory processes in relevant jurisdictions, our financial condition and results of operations, including our ability to raise additional capital for our operations or complete other transactions on favorable terms or at all, regulatory processes and oversight, challenges associated with manufacture or supply of our products to support clinical trials, regulatory inspections and/or commercial sale following any marketing approval, changes in reimbursement and payment policies by government and commercial payers or the application of such policies, intellectual property claims, competitive developments, litigation, and the risks, uncertainties, and other factors described under the heading “Risk Factors” in our Annual Report on Form 10-K filed with the Securities and Exchange Commission on March 31, 2025. Given these risks, uncertainties, and other factors, you should not place undue reliance on these forward-looking statements, and we assume no obligation to update these forward-looking statements, whether as a result of new information, future events or otherwise, except as required by applicable law.