OMEROS CORP

Note 1—Organization and Basis of Presentation

General

Omeros Corporation (“Omeros,” the “Company” or “we”) is a clinical-stage biopharmaceutical company committed to discovering, developing and commercializing small-molecule and protein therapeutics for large-market as well as orphan indications targeting immunologic diseases, including complement-mediated diseases and cancers related to dysfunction of the immune system, as well as addictive and compulsive disorders.

Our clinical-stage development programs include: narsoplimab, our antibody targeting mannan-binding lectin-associated serine protease 2 (“MASP-2”), the effector enzyme of the lectin pathway of complement; OMS1029, our long-acting antibody targeting MASP-2; zaltenibart, also known as OMS906, our antibody targeting mannan-binding lectin-associated serine protease-3 (“MASP-3”), the key activator of the alternative pathway of complement; and OMS527, our phosphodiesterase 7 (“PDE7”) inhibitor program.

Clinical development of narsoplimab is currently focused primarily on hematopoietic stem cell transplant-associated thrombotic microangiopathy (“TA-TMA”). We successfully completed a pivotal clinical trial for narsoplimab in TA-TMA and previously submitted to FDA a biologics license application (“BLA”) seeking marketing approval for narsoplimab in this indication. In October 2021, FDA issued a complete response letter (“CRL”) with respect to the original BLA and indicated that additional information would be needed to support regulatory approval. We appealed FDA’s decision to issue the CRL through a formal dispute resolution process that concluded in late 2022. Although our appeal was denied, the decision identified potential paths for resubmission of the BLA, including paths based on comparison of survival data from the completed pivotal trial to a historical control group. Based on the recommendations included in the appeal decision and on subsequent interactions with FDA’s review division, we developed a statistical analysis plan to assess data from our pivotal clinical trial, existing data from a historical control population available from an external source and data from the narsoplimab expanded access program.

In March 2025, we resubmitted to FDA the BLA seeking regulatory approval for narsoplimab in TA-TMA. The resubmission was accepted for review by FDA as a class 2 resubmission and, pursuant to the Prescription Drug User Fee Act (“PDUFA”), has been assigned a target action date for the FDA decision of September 25, 2025. As with any BLA or new drug application, there can be no guarantee that FDA will complete its review within a given timeframe, or that our BLA will ultimately be approved.

Our lectin pathway program also includes OMS1029, our long-acting antibody targeting MASP-2. We have completed Phase 1 clinical trials evaluating both single-ascending and multiple ascending doses of OMS1029. Results of these studies support once-quarterly dosing administered either intravenously or subcutaneously. OMS1029 has been well tolerated to date with no safety concerns identified. Several indications for potential Phase 2 clinical development of OMS1029 have been evaluated/selected and may be pursued pending the availability and allocation of capital.

Our pipeline of clinical-stage complement-targeted therapeutic candidates also includes zaltenibart, a proprietary, patented monoclonal antibody targeting MASP-3, the key and most proximal activator of the alternative pathway of complement. We have substantially completed two Phase 2 clinical trials evaluating zaltenibart in paroxysmal nocturnal hemoglobinuria (“PNH”) and have an ongoing open label extension study to assess the long-term efficacy and safety of zaltenibart in PNH patients who have completed either of the two Phase 2 clinical trials. We also have a small, ongoing Phase 2 study evaluating zaltenibart in complement 3 glomerulopathy (“C3G”), a rare and debilitating renal disease driven by complement dysregulation.

We began initiating clinical trial sites in our Phase 3 program for zaltenibart in PNH during the first quarter of 2025; however, based on considerations of capital availability and the anticipated ramp up in spending on those trials, we have determined temporarily to pause our Phase 3 clinical development program for zaltenibart in this indication in order to prioritize the use of our available capital to other programs. We are working with our vendors and investigators to ensure that these studies can be restarted with as little disruption to the timeline as possible after securing capital and allocating it to the program.

Our phosphodiesterase 7 (“PDE7”) inhibitor program, which we refer to as OMS527, comprises multiple PDE7 inhibitor compounds and is based on our discoveries of previously unknown links between PDE7 and any addiction or compulsive disorder, and between PDE7 and any movement disorders. In April 2023, we were awarded a grant from the National Institute on Drug Abuse (“NIDA”), part of the National Institutes of Health, to develop, at NIDA’s request, our lead orally administered PDE7 inhibitor compound for the treatment of cocaine use disorder (“CUD”). NIDA awarded the grant to us for a total of $6.24 million over three years, of which we have claimed and received $1.3 million of funding to date. The grant is intended to support preclinical cocaine interaction/toxicology studies to assess safety of the therapeutic candidate in the presence of concomitant cocaine administration, as well as an in-patient, placebo-controlled clinical study evaluating the safety and effectiveness of OMS527 in adults with CUD who receive concurrent intravenous cocaine. The preclinical studies have been completed successfully and provide the drug-interaction safety data necessary to support the human study of OMS527 in CUD. We expect enrollment in the study evaluating OMS527 in adult subjects with CUD to begin in 2025, also fully funded by NIDA with data anticipated to be available late this year or early 2026.

We also have various programs in preclinical research and development.

OMIDRIA Sale and Royalty Monetization Transactions

On December 23, 2021, we closed an Asset Purchase Agreement (the “Asset Purchase Agreement”) with Rayner Surgical Inc. (“Rayner”) for the sale of our commercial product OMIDRIA which we recorded as an OMIDRIA contract asset on our condensed consolidated balance sheet. As a result of the divestiture, the results of OMIDRIA activities are classified as discontinued operations in our condensed consolidated statements of operations and comprehensive loss and excluded from continuing operations for all periods presented (See “Note 7 — Discontinued Operations – Sale of OMIDRIA”).

On September 30, 2022, we sold an interest in a portion of our future OMIDRIA royalty receipts to DRI Healthcare Acquisition LP (“DRI”) and received $125.0 million in cash consideration, which we recorded as an OMIDRIA royalty obligation on our condensed consolidated balance sheet. Interest expense on the royalty obligation is recorded as a component of continuing operations.

On February 1, 2024, we sold an expanded interest in our OMIDRIA royalties to DRI and received $115.5 million in cash consideration, which we recorded as an addition to the OMIDRIA royalty obligation. The amended and restated royalty purchase agreement with DRI (the “Amendment”) eliminates the previously existing annual caps on royalty payments after January 1, 2024, and provides that DRI now receives all royalties on U.S. net sales of OMIDRIA payable between January 1, 2024 and December 31, 2031. All royalties earned on OMIDRIA sales within the U.S. through December 31, 2031 are remitted by Rayner to an escrow account established by Omeros, from which payments are made to DRI. After December 31, 2031, we will retain any U.S. OMIDRIA royalties. We are entitled to retain all royalties on net sales of OMIDRIA outside of the United States. To date, international royalties have not been significant. (See “Note 8 — OMIDRIA Royalty Obligation”).

On June 3, 2024, we, with certain subsidiaries, as guarantors, entered into a Credit and Guaranty Agreement (the “Credit Agreement”) with funds managed by Athyrium Capital Management LP (collectively, “Athyrium”) and funds managed by Highbridge Capital Management, LLC (collectively, “Highbridge”) as Lenders (the “Lenders”). The Credit Agreement provides for a senior secured term loan facility of up to $92.1 million, consisting of a term loan of $67.1 million (the “Term Loan”) and a $25.0 million delayed draw term loan (the “Delayed Draw Term Loan”), which may be drawn once in full upon notice delivered on or prior to June 3, 2025, conditioned on receipt of FDA approval of narsoplimab in TA-TMA within 30 days of the notice. Based on the September 2025 target date for FDA action assigned to the narsoplimab BLA, we do not expect to meet the conditions required to utilize the Delayed Draw Term Loan.

Also, we used the Term Loan proceeds along with $21.7 million of cash on hand, to repurchase from the Lenders $118.1 million aggregate principal amount of our existing 5.25% convertible senior notes due on February 15, 2026 (the “2026 Notes” and such repurchase, the “2026 Note Repurchase Transaction”), which resulted in a $51.0 million reduction in our total debt outstanding. (See “Note 6 — Debt” for a description of the Credit Agreement provisions).

Basis of Presentation

Our condensed consolidated financial statements include the financial position and results of operations of Omeros and our wholly owned subsidiaries. All inter-company transactions have been eliminated. The accompanying condensed consolidated financial statements reflect all adjustments, consisting of normal recurring adjustments and non-recurring adjustments, considered necessary for the fair presentation of such information. Our financial statements have been prepared in accordance with U.S. generally accepted accounting principles (“GAAP”).

These financial statements should be read in conjunction with the audited financial statements and notes thereto included in our Annual Report on Form 10-K for the year ended December 31, 2024, from which the December 31, 2024, condensed consolidated balance sheet has been derived.

Liquidity and Capital Resources

As of March 31, 2025, we had cash, cash equivalents and short-term investments of $52.4 million. For the three months ended March 31, 2025, our cash used in operations was $35.8 million and included a net loss for the quarter of $33.5 million. Pursuant to a covenant in the Credit Agreement entered on June 3, 2024, we must maintain $25.0 million of unrestricted cash, cash equivalents and short-term investments at all times. (See “Note 6 — Debt”).

In recent years, Omeros has incurred net losses from continuing operations and negative cash flows from operations. The recurring losses, in combination with our cash and investment balances as of March 31, 2025, along with the maturity of the 2026 Notes on February 15, 2026, raises substantial doubt about our ability to continue as a going concern. The accompanying condensed consolidated financial statements do not include any adjustments to reflect the possible future effects on the recoverability and classification of assets or the amounts and classification of liabilities that may result from uncertainty related to our ability to continue as a going concern.

As we currently do not have an ongoing source of revenue sufficient to cover our operating costs, we will need to raise additional capital to accomplish our business plan.

On May 14, 2025, we completed the exchange (the “Convertible Note Exchange”) of $70.8 million of our 2026 Notes on a one-for-one basis for newly issued convertible senior notes maturing on June 15, 2029 (the “2029 Notes”). The Convertible Note Exchange was conducted with a limited number of holders of the 2026 Notes pursuant to exchange agreements dated as of May 12, 2025.

On May 12, 2025, the Company entered into note conversion agreements (each, a “Note Conversion Agreement”) with two affiliated holders of the 2026 Notes to convert $10.0 million aggregate principal amount of 2026 Notes into shares of the Company’s common stock (the “Equitization Transaction”). Under the terms of the Note Conversion Agreements, the holders will convert the equitized principal amount of the 2026 Notes in three equal tranches for a number of shares of common stock to be determined based in part on the closing price of the Company’s common stock on May 9, 2025 and in part based on the 20-day volume-weighted average price applicable to each tranche conversion date, subject to a floor conversion price. The Note Conversion Agreements provide that the final settlement will occur no later than September 15, 2025.

The Convertible Note Exchange reduced the aggregate principal balance of our 2026 Notes from $97.9 million to $27.1 million. As a result of the reduced principal balance of the 2026 Notes, the Company will no longer be required to make a $20.0 million prepayment of the Term Loan outstanding under the Credit Agreement which otherwise would have been required to be paid in November 2025 to avoid accelerated maturity of the entire Term Loan balance (see “Note 6 — Debt”). Upon completion of the Equitization Transaction, the aggregate principal balance of our 2026 Notes will be further reduced from $27.1 million to $17.1 million. No new cash was received as a result of these transactions. The accompanying condensed consolidated balance sheet as of March 31, 2025 reflects the reclassification from current to non-current on May 14, 2025 of the 2026 Notes that were acquired in the Convertible Note Exchange and that are subject to the Note Conversion Agreement.

To raise capital for our operations, we may also pursue public and private offerings of our equity securities, additional debt transactions or restructuring, future royalty sales, or other strategic transactions, which may include licensing or selling a portion or all of one or more of our existing technologies. However, pursuing debt financings, certain equity offerings or other strategic transactions may result in mandatory prepayments of the Term Loan to the Credit Agreement. (See “Note 6 — Debt” for further details).

In addition, we have a sales agreement pursuant to an at the market (“ATM”) equity offering facility through which we may, from time to time, offer and sell shares of our common stock equaling an aggregate amount of up to $150.0 million. Subsequent to March 31, 2025, we received $3.5 million in net proceeds from sale of our common stock through the ATM facility.

If these capital resources, for any reason, are needed but inaccessible, it would have a significant negative impact on our financial condition. For purposes of determining available capital resources, any future royalty and/or milestone receipts are excluded. We have taken steps to manage our operating expenses and reduce our projected cash requirements by delaying clinical trials and reducing selected research and development efforts. Should it be necessary, we may determine to further reduce or delay these or other aspects of our operations and/or implement other restructuring activities.

The conditions described above, including the need to raise additional capital, when evaluated in accordance with the relevant accounting literature, raise substantial doubt with respect to our ability to meet our obligations through one year from the issuance of the Company's condensed consolidated financial statements.

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Use of Estimates

The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. Significant items subject to such estimates include the OMIDRIA contract royalty asset valuation and the OMIDRIA royalty obligation valuation. We base our estimates on historical experience and on various other factors that we believe are reasonable under the circumstances; however, actual results could differ from these estimates.

Note 2—Significant Accounting Policies

Segment Reporting

We operate inone business segment focusing on the research, discovery, development and commercialization of small-molecule and protein therapeutics targeting immunologic diseases, including complement-mediated diseases and cancers related to dysfunction of the immune system, as well as addictive and compulsive disorders. The Company defines its operating segment based on internally reported financial information that is regularly used by the Chief Operating Decision Maker (“CODM”) to analyze performance, make decisions and allocate resources. The Company's CODM is our Chief Executive Officer. For the three months ended March 31, 2025, the Company has identifiedone operating and reportable segment. The CODM reviews net loss and expenses reported on the condensed consolidated statement of operations and comprehensive income (loss). The measurement of segment assets is reported on the balance sheet as total consolidated assets. All long-lived assets are held in the U.S. Our segment net income (loss) aligns with our condensed consolidated statement of operations and comprehensive income (loss).

Discontinued Operations

We review the presentation of planned or completed business dispositions in the condensed consolidated financial statements based on the available information and events that have occurred. The review consists of evaluating whether the business meets the definition of a component for which the operations and cash flows are clearly distinguishable from the other components of the business and, if so, whether it is anticipated that, after the disposal, the cash flows of the component would be eliminated from continuing operations and whether the disposition represents a strategic shift that has a major effect on operations and financial results.

Planned or completed business dispositions are presented as discontinued operations when all the criteria described above are met. For those divestitures that qualify as discontinued operations, all comparative periods presented are reclassified in the condensed consolidated balance sheets. Additionally, the results of operations of a discontinued operation are reclassified to income from discontinued operations, net of tax, for all periods presented in the condensed consolidated statements of operations and comprehensive income (loss). Results of discontinued operations include all revenues and expenses directly derived from such businesses. General corporate overhead is not allocated to discontinued operations. The OMIDRIA asset sale to Rayner qualifies as a discontinued operation and has been presented as such for all reporting periods presented. The Company included information regarding cash flow from discontinued operations (See “Note 7 — Discontinued Operations – Sale of OMIDRIA”).

OMIDRIA Royalties, Milestones and Contract Royalty Assets

We have rights to receive future royalties from Rayner on OMIDRIA net sales at royalty rates that vary based on geography and certain regulatory contingencies. Therefore, future OMIDRIA royalties are treated as variable consideration. The sale of OMIDRIA qualified as an asset sale under GAAP. To measure the OMIDRIA contract royalty asset, we use the expected value approach which is the sum of the discounted probability-weighted royalty payments we would receive using a range of potential outcomes, to the extent that it is probable that a significant reversal in the amount of cumulative income recognized will not occur.

The royalty rate applicable to U.S. net sales of OMIDRIA is 30% until the expiration or termination of the last issued and unexpired U.S. patent, which we expect to occur no earlier than 2035. Royalties earned are recorded as a reduction to the OMIDRIA contract royalty asset. All royalties received from Rayner, other than royalties related to any sales outside the U.S. and any royalties received after December 31, 2031, are passed through directly to DRI and are accounted for as interest expense and a reduction of the OMIDRIA royalty obligation. The amount recorded in discontinued operations in future periods will reflect interest earned on the outstanding OMIDRIA contract royalty asset at 11.0% and any amounts we receive that are different from the expected royalties. The OMIDRIA contract royalty asset is re-measured quarterly using the expected value approach, which incorporates actual results and future expectations. Any required adjustment to the OMIDRIA contract royalty asset is recorded in discontinued operations.

OMIDRIA Royalty Obligation

On September 30, 2022, we sold to DRI an interest in a portion of our future OMIDRIA royalty receipts for a purchase price of $125.0 million and recorded an OMIDRIA Royalty Obligation for the same amount. On February 1, 2024, DRI purchased our remaining U.S. OMIDRIA royalty receipts through December 31, 2031 for $115.5 million in cash, which increased the OMIDRIA royalty obligation by the same amount. The OMIDRIA royalty obligation is valued based on our estimates of future OMIDRIA royalties and is amortized through December 31, 2031 using the implied effective interest rate of 10.27%. Interest expense is recorded in continuing operations.

To the extent our estimates of future royalties differ materially from previous estimates, we will adjust the carrying amount of the OMIDRIA royalty obligation to reflect the present value of the revised estimated cash flows, discounted at the implied effective interest rate of 10.27% utilizing the cumulative catch-up method. This is reflected as a remeasurement adjustment recognized as non-cash interest expense, a component of net income (loss) from continuing operations (See “Note 8 — OMIDRIA Royalty Obligation”).

Inventory

We expense inventory costs related to product candidates as research and development expenses until regulatory approval is reasonably assured in the U.S. or the European Union (“EU”). Once approval is reasonably assured, costs, including amounts related to third-party manufacturing, transportation and internal labor and overhead, will be capitalized.

Right-of-Use Assets and Related Lease Liabilities

We record operating leases as right-of-use assets and recognize the related lease liabilities equal to the fair value of the lease payments using our incremental borrowing rate when the implicit rate in the lease agreement is not readily available. We recognize variable lease payments when incurred. Costs associated with operating lease assets are recognized on a straight-line basis within operating expenses over the term of the lease.

We record finance lease obligations as a component of property and equipment and amortize these assets within operating expenses on a straight-line basis to their residual values over the shorter of the term of the underlying lease or the estimated useful life of the equipment. The interest component of finance lease obligations is included in interest expense and recognized using the effective interest method over the lease term.

We account for leases with initial terms of 12 months or less as an operating expense.

In June 2024, we performed an assessment of the Credit Agreement which was entered into with Highbridge and Athyrium and determined that it met the criteria to be accounted for as a troubled debt restructuring. As a result, the $29.3 million difference between the $118.1 million aggregate principal amount of the 2026 Notes repurchased by the Company and the $88.8 million aggregate repurchase price (consisting of the $67.1 million Term Loan and $21.7 million cash on hand) was recorded as a premium (i.e. an increase) to the term debt recorded on the Company's condensed consolidated balance sheet instead of being recognized as a gain on early extinguishment of debt. We amortize the premium as both a reduction of term debt in the condensed consolidated balance sheet and interest expense in the condensed consolidated statement of operations and comprehensive income (loss) over the duration of the term loan.

Income Taxes

Deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their tax basis. Deferred tax assets and liabilities are measured using enacted tax rates applied to taxable income in the years in which those temporary differences are expected to be recovered or settled. We recognize the effect of income tax positions only if those positions are more likely than not of being sustained upon an examination by the relevant taxing authority. A valuation allowance is established when it is more likely than not that the deferred tax assets will not be realized.

Financial Instruments and Concentrations of Credit Risk

Cash and cash equivalents, receivables, accounts payable and accrued liabilities, which are recorded at invoiced amount or cost, approximate fair value based on the short-term nature of these financial instruments. The fair value of short-term investments is based on quoted market prices. Financial instruments that potentially subject to concentrations of credit risk consist primarily of cash and cash equivalents, short-term investments and receivables. At times, our cash and cash equivalents balance held at financial institutions may exceed the federally insured limits. To limit the credit risk, we invest our excess cash in high-quality securities such as money market mutual funds, certificates of deposit and U.S. treasury bills.

Recent Accounting Pronouncements

In December 2023, the Financial Accounting Standards Board (“FASB”) issued ASU 2023-09,* Income Taxes - Improvements to Income Tax Disclosure* (Topic 740), to enhance the transparency of income tax disclosures. ASU 2023-09 provides enhancements to the income tax disclosures related to the rate reconciliation and income taxes paid information. ASU 2023-09 is effective for annual years beginning after December 15, 2024 and applied prospectively. The Company is evaluating the impact of this pronouncement on its consolidated financial statements.

In November 2024, the FASB issued ASU 2024-03,Income Statement - Reporting Comprehensive Income - Expense Disaggregation Disclosures (Subtopic 220-40):Disaggregation of Income Statement Expense, requiring public entities to disclose additional information about specific expense categories in the notes to the financial statements on an interim and annual basis. ASU 2024-03 is effective for annual years beginning after December 15, 2026, and for interim periods beginning after December 15, 2027, with early adoption permitted. The Company is currently evaluating the impact on its financial statement disclosures.

In November 2024, the FASB issued ASU 2024-04,Debt - Debt with Conversion and Other Options (Subtopic 470-20): Induced Conversions of Convertible Debt Instruments, which provides clarification on the accounting treatment of convertible debt settlements that occur under terms differing from those of the original instrument. The amendments specify that if the settlement is considered an induced conversion, an entity must recognize an inducement expense at the offer acceptance date. Conversely, if the settlement is treated as a debt extinguishment, an entity must recognize a gain or loss at the extinguishment date. This ASU is effective for all entities for annual years beginning after December 15, 2025, including interim periods within those years, with early adoption permitted. The Company is in the process of assessing the potential impact of this ASU on its debt accounting policies.

Note 3—Net Loss Per Share

Basic net income (loss) per share (“Basic EPS”) is computed by dividing net income (loss) by the weighted average number of common shares outstanding during the period. Diluted net income (loss) per share (“Diluted EPS”) is computed by dividing net income (loss) by the weighted average number of common shares and potentially dilutive common shares outstanding during the period. Our potential dilutive securities include common shares related to our stock options and convertible senior notes calculated using the treasury stock method. In periods where we have a net loss from continuing operations but overall net income, we do not compute Diluted EPS because the effect would be anti-dilutive. Potentially dilutive securities excluded from Diluted EPS are as follows:

Note 4—Investments and Fair-Value Measurements

All of our investments are short-term and held in our name. Money market funds are classified as available-for-sale on the accompanying condensed consolidated balance sheets. Interest income is included as a component of interest and other income on our condensed consolidated statement of operations and comprehensive loss. Interest and other income for the three months ended March 31, 2025 and March 31, 2024 consists primarily of interest earned of $0.7 million and $2.8 million, respectively.

The following tables summarize our investments:

Fair value is defined as the exchange price that would be received for an asset or paid to transfer a liability, an exit price, in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. The accounting standard establishes a fair value hierarchy that requires an entity to maximize the use of observable inputs, where available. The following summarizes the three levels of inputs required:

Level 1—Observable inputs for identical assets or liabilities, such as quoted prices in active markets;

Level 2—Inputs other than quoted prices in active markets that are either directly or indirectly observable; and

Level 3—Unobservable inputs in which little or no market data exists, therefore they are developed using estimates and assumptions developed by us, which reflect those that a market participant would use.

Our fair value hierarchy for our financial assets and liabilities are as follows:

Cash held in demand deposit accounts of $4.3 million and $3.4 million is excluded from our fair-value hierarchy disclosure as of March 31, 2025 and December 31, 2024, respectively. The carrying amounts reported in the accompanying condensed consolidated balance sheets for receivables, accounts payable and accrued liabilities, and other current monetary assets and liabilities approximate fair value.

See “Note 6 — Debt” and “Note 8 — OMIDRIA Royalty Obligation” for the carrying amount and estimated fair value of our outstanding term loan, convertible senior notes and the OMIDRIA royalty obligation.

Note 5—Certain Balance Sheet Accounts

OMIDRIA Contract Royalty Asset

The OMIDRIA contract royalty asset consists of the following:

See “Note 7 — Discontinued Operations – Sale of OMIDRIA” for discussion regarding the estimated fair value of our OMIDRIA contract royalty asset.

Receivables

Receivables consist of the following:

Other receivables of $1.4 million includes $1.1 million of royalties paid by Rayner representing escrowed funds in-transit to DRI and received on April 1, 2025. These funds are also recorded as a current OMIDRIA royalty obligation during the quarter.

Property and Equipment, Net

Property and equipment, net consists of the following:

For the three months ended March 31, 2025 and 2024, depreciation and amortization expense was $0.3 million and $0.2 million, respectively.

Accrued Expenses

Accrued expenses consist of the following:

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Note 6—Debt

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2024 Secured Term Loan

On June 3, 2024, we entered into a Credit Agreement with the Lenders, pursuant to which we have a Term Loan of $67.1 million. The Credit Agreement also provides for a Delayed Draw Term Loan of $25.0 million conditioned on the receipt of FDA approval of narsoplimab for TA-TMA within 30 days of a draw notice delivered no later than June 3, 2025, but we do not expect to meet this condition based on the September 25, 2025 target date for FDA action on our narsoplimab BLA. At any time prior to November 1, 2025, the Company, at its sole discretion, may exchange up to $14.9 million aggregate principal amount of outstanding 2026 Notes for cash and/or additional term loan amounts, with the holders of such notes becoming Lenders under the Credit Agreement (any such additional term loans, together with the Term Loan and the Delayed Draw Term Loan, the “Loans”). As of May 15, 2025, no such additional exchanges for additional term loans have occurred. All indebtedness under the Credit Agreement is secured by a first-priority security interest in and lien on substantially all our tangible and intangible property, subject to customary exceptions, and excluding royalty interests in OMIDRIA and certain related rights.

In connection with our entry into the Credit Agreement, we used the Term Loan along with $21.7 million of cash on hand to repurchase $118.1 million aggregate principal amount of the 2026 Notes held by the Lenders. The total consideration paid at closing of $88.8 million represented a purchase price equal to approximately 75% of the par value of the 2026 Notes retired in the transaction. The reduction in the aggregate outstanding principal balance of our 2026 Notes and incurrence of a new Term Loan resulted in a $51.0 million reduction of our outstanding debt. The $29.3 million difference between the $118.1 million aggregate principal amount of the 2026 Notes and the $88.8 million aggregate repurchase price was recorded as a premium (i.e., an increase) to the long-term debt on the Company’s condensed consolidated balance sheet instead of being recognized as a gain on early extinguishment of debt. The premium is being amortized as both a non-cash reduction of long-term debt in the condensed consolidated balance sheets and interest expense in the condensed consolidated statement of operations and comprehensive loss over the duration of the term loan.

The amount outstanding on the Term Loan is as follows:

The Loans have a stated maturity date of June 3, 2028 and bear interest at an adjusted secured overnight financing rate (“adjusted SOFR”), subject to a 3.00% floor, plus 8.75% per annum, payable quarterly from the closing date. As of March 31, 2025, the contractual interest rate on the Loans was 13.17%. We have the option to pay all of the interest in cash or to pay 50% in cash and pay-in-kind (“PIK”), the remaining interest. When this provision is elected, interest for the quarter, including both the cash interest and PIK interest, is calculated based on adjusted SOFR plus a 10.25% PIK margin (instead of the customary 8.75% margin). The PIK interest is then added to the outstanding principal balance and interest is computed using the original adjusted SOFR plus 8.75% margin rate. Due to the premium amortization on the Term Loan, interest expense is currently being recognized at an implied effective interest rate of 1.43%.

The following table sets forth interest expense recognized related to the Term Loan:

We may elect to prepay the Loans, in whole or in part, in cash, plus an applicable prepayment and/or make-whole premium. Under certain circumstances, we are required to prepay all or a portion of the outstanding Loans, plus an applicable prepayment and/or make-whole premium, as described below.

(1) If, on November 1, 2025, (i) the aggregate outstanding principal amount of the outstanding 2026 Notes that is not held by the Lenders equals or exceeds $38.5 million and (ii) we have not made or delivered notice that we expect to make certain voluntary or mandatory prepayments under the Credit Agreement of at least $20.0 million in the aggregate, then we would be required, on or prior to November 15, 2025, to make a $20.0 million mandatory prepayment, together with a $1.0 million prepayment premium to avoid accelerated maturity of the entire Term Loan balance. As a result of the Convertible Note Exchange completed on May 14, 2025, the prepayment requirement is no longer applicable because the outstanding principal amount under the 2026 Notes was reduced below $38.5 million. As a result, the accompanying condensed consolidated balance sheet as of March 31, 2025 reflects the entire Term Loan balance of $67.1 million as a long-term liability.

(2) Upon the occurrence of a change in control, we must prepay the entire outstanding amount of the Loans, plus the applicable make-whole or prepayment premium.

(3) We must prepay the Loans in an amount equal to: (i)25.0% of any milestone payments received from DRI or its affiliates on the basis of net sales of OMIDRIA; (ii)60.0% of the net cash proceeds (excluding transaction expenses and certain milestone payments) received by Omeros from the sale or license of our assets (or in the case of an asset sale or license involving narsoplimab that occurs while any Delayed Draw Term Loan is outstanding, an amount equal to 100% of the net cash proceeds from such transaction); (iii)100.0% of net cash proceeds of indebtedness incurred by the Company other than as permitted by the Credit Agreement; and (iv)100% of the net cash proceeds of insurance recoveries on loss of property, except to the extent utilized to repair or replace the relevant assets within a specified time.

Voluntary and mandatory prepayments of the Loans are subject to payment of the following premiums: (i) during the first year of such Loans, a make-whole premium plus 5.0% of the applicable prepayment amount (unless the prepayment is made in contemplation of a change of control, in which case only the make-whole premium would be payable); (ii) during the second year, a prepayment premium equal to 5.0% of the applicable prepayment amount; and (iii) during the third year, a prepayment premium equal to 3.0% of the applicable prepayment amount.

The Credit Agreement contains certain customary default provisions, representations and warranties and affirmative and negative covenants. These include a covenant requiring us to maintain at all times unrestricted cash, cash equivalents and short-term investments of at least $25.0 million in accounts subject to control agreements and a covenant limiting the use of cash for open market or privately negotiated repurchases of any outstanding 2026 Notes to: (i) an initial amount not exceeding $25.0 million, which may be increased by up to an additional $10.0 million subject to the satisfaction of certain conditions; (ii) an unlimited amount, if the amount of the Loans outstanding at the time of repurchase does not exceed $38.5 million; and (iii) an additional amount not to exceed 50% of the net cash proceeds from an equity offering, provided that the Company offers to prepay an equal amount of the Loans with the net cash proceeds of such offering. As of March 31, 2025, the Company was in compliance with the covenants under the Credit Agreement. After review of the customary default provisions, affirmative and negative covenants, and voluntary and mandatory prepayment options, this resulted in a net derivative asset that was not significant as of March 31, 2025. A default under the Credit Agreement that results in the outstanding debt thereunder being declared due and payable prior to the stated maturity would constitute a cross-default under the indenture governing the 2026 Notes. In such an event, the principal and all accrued and unpaid interest on the 2026 Notes may be declared immediately due and payable either by the trustee under the indenture, or by holders of at least 25% of the aggregate principal amount of the 2026 Notes outstanding.

The fair value of the Loans is classified as a Level 3 liability. As of March 31, 2025 and December 31, 2024, the approximate fair value of our Loan obligations was $70.2 million and $69.5 million, respectively. We determined the fair market value by discounting the future cash flows based on adjusted SOFR at each measurement date.

2026 Unsecured Convertible Senior Notes

We have outstanding unsecured convertible senior notes which accrue interest at an annual rate of 5.25% per annum, payable semi-annually in arrears on February 15 and August 15 of each year. The 2026 Notes mature on February 15, 2026, unless earlier purchased, redeemed or converted in accordance with their terms.

In 2024, we repurchased $118.1 million of principal amount outstanding on our 2026 Notes for total consideration of $88.8 million (approximately 75% of par value), using proceeds from the Term Loan of $67.1 million and paying $21.7 million of cash on hand.

On May 14, 2025, we completed the Convertible Note Exchange in which we exchanged $70.8 million in aggregate principal of our 2026 Notes for a like principal amount of our 2029 Notes. The Convertible Note Exchange reduced the principal balance of our 2026 Notes from $97.9 million to $27.1 million. In addition, on May 12, 2025, we entered into the Equitization Transaction, which will result in conversion of an additional $10.0 million aggregate principal amount of our 2026 Notes into shares of the Company's common stock, to be delivered in three approximately equal tranches on or prior to September 15, 2025.

Amounts outstanding on our 2026 Notes as of March 31, 2025 and December 31, 2024 are as follows:

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Unamortized debt issuance costs represent an allocation of the $0.5 million of debt issuance costs under the original 2026 Notes as of March 31, 2025. We have amortized interest expense on the 2026 Notes at an effective interest rate of 5.89%.

The following table sets forth interest expense recognized related to the 2026 Notes:

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The conversion rate is 54.0906 shares of our common stock per $1,000 of note principal (equivalent to an initial conversion price of approximately $18.4875 per share of common stock), which equals approximately 5.3 million shares issuable upon conversion, subject to adjustment in certain circumstances.

The 2026 Notes are convertible at the option of the holders on or after November 15, 2025 at any time prior to the close of business on February 12, 2026, the second scheduled trading day immediately before the stated maturity date of February 15, 2026. Additionally, holders may convert their 2026 Notes at their option at specified times prior to the maturity date only if:

(1) during any calendar quarter, the last reported sale price per share of our common stock exceeds 130% of the conversion price of the 2026 Notes for each of at least 20 trading days, whether or not consecutive, in the period of 30 consecutive trading days ending on, and including, the last trading day of the immediately preceding calendar quarter;

(2) during thefive consecutive business days immediately after anyfive-consecutive-trading-day period (such five-consecutive-trading-day period, the “measurement period”) in which the trading price per $1,000 principal amount of 2026 Notes for each trading day of the measurement period was less than 98% of the product of the last reported sale price per share of our common stock on such trading day and the conversion rate on such trading day;

(3) there is an occurrence of one or more certain corporate events or distributions of our common stock; or

(4) we call the 2026 Notes for redemption.

We will settle any conversions by paying or delivering, as applicable, cash, shares of our common stock or a combination of cash and shares of our common stock, at our election, based on the applicable conversion rate(s).

Subject to the satisfaction of certain conditions, we may redeem in whole or in part the 2026 Notes at our option beginning August 15, 2023 through the 50 th scheduled trading day immediately before the maturity date at a cash redemption price equal to the principal amount of the 2026 Notes to be redeemed plus any accrued and unpaid interest. The 2026 Notes are subject to redemption only if certain requirements are satisfied, including that the last reported sale price per share of our common stock exceeds 130% of the conversion price on (i) each of at least 20 trading days, whether or not consecutive, during the 30 consecutive trading days ending on, and including, the trading day immediately before the date we send the related redemption notice and (ii) the trading day immediately before the date we send such notice.

In order to reduce the dilutive impact or potential cash expenditure associated with the conversion of the 2026 Notes, we entered into capped call transactions in connection with the issuances of the 2026 Notes (the “2026 Capped Call”). The 2026 Capped Call will cover, subject to anti-dilution adjustments substantially similar to those applicable to the 2026 Notes, the number of shares of common stock underlying the 2026 Notes when our common stock is trading within the range of approximately $18.49 and $26.10. However, should the market price of our common stock exceed the $26.10 cap, then the conversion of the 2026 Notes would have an additional dilutive impact or may require a cash expenditure to the extent the market price of our common stock exceeds the cap price. The 2026 Capped Call will expire on various dates over the 50-trading-day period ranging from December 2, 2025 to February 12, 2026, if not exercised earlier. The 2026 Capped Call is a separate transaction and not part of the terms of the 2026 Notes and was executed separately from the issuance of the 2026 Notes. The amount paid for the 2026 Capped Call was recorded as a reduction to additional paid-in capital in the condensed consolidated balance sheet. As of March 31, 2025, approximately 12.2 million shares remained outstanding under the 2026 Capped Call. We also retain all potential future value of the capped call purchased in connection with the issuance of the 2026 Notes covering all shares underlying the original 2026 Notes.

Further, we concluded the 2026 Capped Call qualifies for a derivative scope exception for instruments that are both indexed to an entity’s own stock and classified in stockholders’ equity in its balance sheet. Consequently, the fair value of the 2026 Capped Call of $23.2 million is classified as equity, not accounted for as derivatives, and will not be subsequently remeasured.

Minimum Commitments

As of March 31, 2025, the most probable principal payments on our convertible notes and the Term Loan are as follows and reflects the impact of refinancing our 2026 Notes from short-term to long-term:

Note 7—Discontinued Operations - Sale of OMIDRIA

On December 23, 2021, we sold the rights to OMIDRIA and related assets to Rayner, which is reported as discontinued operations in our condensed consolidated statements of operations and comprehensive loss and excluded from continuing operations for all periods presented.

The results of operations for OMIDRIA are recorded as income from discontinued operations for all periods presented in the condensed consolidated statements of operations and comprehensive loss are as follows:

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The following is a roll forward of the OMIDRIA contract royalty asset (in thousands):

We remeasure the OMIDRIA contract royalty asset on a quarterly basis using the expected value approach, which incorporates actual results and future expectations.

Cash flow from discontinued operations is as follows:

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Net cash provided by discontinued operations primarily represents royalties received from Rayner. ​All royalties earned on OMIDRIA sales within the U.S. through December 31, 2031 are remitted by Rayner to an escrow account established by Omeros, from which payments are made to DRI.

Note 8—OMIDRIA Royalty Obligation

In September 2022, we sold to DRI an interest in our future OMIDRIA royalty receipts and received $125.0 million in cash consideration, which was recorded as an OMIDRIA royalty obligation on our condensed consolidated balance sheet. DRI was entitled to receive royalties on OMIDRIA net sales between September 1, 2022 and December 31, 2030, subject to annual caps.

In February 2024, Omeros and DRI expanded their royalty purchase agreement under the Amendment, resulting the elimination of previously existing annual caps on royalty payments and Omeros receiving an additional $115.5 million in cash consideration, which we accounted for as a modification of our existing debt from DRI. All royalties earned on OMIDRIA sales within the U.S. through December 31, 2031 are remitted by Rayner to an escrow account established by Omeros, from which payments are made to DRI.

We retain the right to receive all royalties payable by Rayner on any U.S. net sales of OMIDRIA after December 31, 2031 and all royalties on global net sales of OMIDRIA from and after December 31, 2031. To date, international royalties have not been significant. DRI has no recourse to our assets other than its interest in OMIDRIA royalties.

We are also entitled to receive a milestone payment ranging between $10.0 million and $27.5 million if U.S. net sales of OMIDRIA reach applicable thresholds ranging between a total of $156.0 million and $160.0 million for any period of four consecutive quarters prior to January 1, 2026. In addition, we are entitled to receive a separate milestone payment ranging between $8.0 million and $27.5 million if U.S. net sales of OMIDRIA reach applicable thresholds ranging between a total of $181.0 million and $185.0 million for any period of four consecutive quarters prior to January 1, 2028.

The changes in the OMIDRIA royalty obligation during the three months ended March 31, 2025 are as follows (in thousands):

The OMIDRIA royalty obligation is classified as a Level 3 liability as its valuation requires substantial judgment and estimation of factors that are not currently observable in the market. The fair value of the OMIDRIA royalty obligation is determined by calculating the net present value of our estimated future OMIDRIA cash flows using the interest rate at inception of our royalty purchase agreement with DRI, adjusted for the change in the prime rate through the measurement date. As of March 31, 2025 and December 31, 2024, the approximate fair value of our obligation was $204.9 million and $209.7 million, respectively.

For the three months ended March 31, 2025 and 2024, we incurred interest expense of $1.8 million and $5.0 million, respectively.

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As of March 31, 2025, the expected scheduled principal and interest payments (based on an implied effective interest rate of 10.27%) are as follows:

Note 9—Lease Liabilities

We have an operating lease for our office and laboratory facilities with an initial term that ends in November 2027 andtwo options to extend the lease term by an additional five years each. Restricted investments of $1.1 million represent the security deposit on our office and laboratory facilities. We have finance leases for certain laboratory and office equipment that have lease terms expiring through October 2029.

Supplemental lease information is as follows:

The supplemental cash flow information related to leases is as follows:

Note 10—Commitments and Contingencies

Good and Service Contracts

We have various agreements with third parties that collectively require payment of termination fees totaling $4.4 million as of March 31, 2025 if we cancel the work within specific time frames, either prior to commencing or during performance of the contracted services.

Development Milestones and Product Royalties

We have entered a variety of development, collaboration, licensing or similar agreements with third parties under which we have accessed technology or services in connection with our development assets and programs. Some of these agreements require milestone payments based on achievements of development, regulatory or sales milestones, and/or low-single to low-double digit royalties on net income or net sales of the relevant product. For the three months ended March 31, 2025 and 2024, development milestone expenses were not significant.

Note 11—Shareholders’** Deficit**

Common Stock

At the Market Sales Agreement - We have a sales agreement to sell shares of our common stock having an aggregate offering price of up to $150.0 million, from time to time, through an ATM equity offering program. Subsequent to March 31, 2025, we sold 0.5 million shares of common stock pursuant to our ATM program, generating net proceeds of $3.5 million at an average price per share of $6.94.

Share Repurchase Program - On November 9, 2023, the Board of Directors approved a share repurchase program under which we were permitted to repurchase from time to time up to $50.0 million of our common stock in the open market or through privately negotiated transactions. From inception through its termination in June 2024, we repurchased and retired 5.0 million shares at an average price of $3.30 per share. During the first quarter of 2024, we repurchased and retired 3.2 million shares of common stock at an average share price of $3.71 at an aggregate cost of $11.9 million.

Note 12—Stock-Based Compensation

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Our stock option plans provide for the grant of incentive and non-qualified stock options, restricted stock awards, restricted stock units, and other stock awards to employees, non-employee directors and consultants.

Stock-based compensation is as follows:

The fair value of each option grant is estimated on the date of grant using the Black-Scholes option-pricing model. The following assumptions were applied to all stock option grants:

Expected volatility is based on the historical volatility of our stock price weighted by grant issuances over the reporting period. We estimated the expected life of the stock options granted using the historical exercise behavior of option holders. The risk-free interest rate is based on the U.S. Treasury yield curve in effect at the time of grant. Forfeiture expense is estimated at the time of grant and revised in subsequent periods if actual forfeitures differ from those estimates.

Stock option activity for all stock plans and related information is as follows:

Of the 16.6 million common stock options outstanding as of March 31, 2025,8.2 million have an exercise price per share above $8.22, which was the closing price of our stock on the Nasdaq exchange on March 31, 2025.

As of March 31, 2025, there were 4.8 million unvested options outstanding that will vest over a weighted-average period of 2.4 years. The total estimated compensation expense yet to be recognized on outstanding options is $10.4 million.

As of March 31, 2025, the total number of shares of common stock available for grant was 6.9 million.