OMEROS CORP (OMER)

ITEM 7.       MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

The following discussion and analysis should be read in conjunction with the audited annual consolidated financial statements and the related notes thereto included elsewhere in this Annual Report on Form 10-K. This discussion contains forward-looking statements reflecting our current expectations that involve risks and uncertainties. Actual results may differ materially from those discussed in these forward-looking statements due to a number of factors, including those set forth in the section entitled “Risk Factors” and elsewhere in this Annual Report on Form 10-K. For further information regarding forward-looking statements, please refer to the special note regarding forward-looking statements at the beginning of this Annual Report on Form 10-K. Throughout this discussion, unless the context specifies or implies otherwise, the terms “Company,” “we,” “us” and “our” refer to Omeros Corporation and our wholly owned subsidiaries.

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Overview

We are a clinical-stage biopharmaceutical company committed to discovering, developing and commercializing first-in-class 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.

Complement Inhibitor Programs

The complement system plays a role in the body’s inflammatory response and becomes activated as a result of tissue damage or trauma or microbial pathogen invasion. Inappropriate or uncontrolled activation of the complement system can cause diseases characterized by serious tissue injury. Three main pathways can activate the complement system: classical, lectin, and alternative. We are focused on development of therapeutics to treat diseases associated with the lectin and/or alternative pathways of complement. We are developing antibodies as well as small-molecule inhibitors of key enzymes known to be centrally involved in the in activation of the targeted pathway of complement.

Lectin Pathway / MASP 2

MASP-2 is a novel pro-inflammatory protein target that is the effector enzyme of the lectin pathway and is required for the function of this pathway. We are developing antibodies and small-molecule inhibitors of MASP-2 as potential therapeutics for diseases in which the lectin pathway has been shown to contribute to significant tissue injury and pathology. When not treated, these diseases are typically characterized by significant end-organ damage, such as kidney or central nervous system injury. Importantly, inhibition of MASP-2 has been demonstrated not to interfere with the antibody-dependent classical complement activation pathway, a critical component of the acquired immune response to infection.

The lead product candidate in our pipeline of complement-targeted therapeutics is narsoplimab (OMS721), a proprietary, patented human monoclonal antibody targeting MASP-2, the key activator of the lectin pathway of complement. Clinical development of narsoplimab is currently focused primarily on TA-TMA and development efforts are also directed to COVID-19, ARDS and PASC. We are also developing OMS1029, our long-acting antibody targeting MASP-2 which we expect will be well-suited to indications requiring long-term, chronic administration. In addition, we are advancing our orally administered small-molecule MASP-2 inhibitor through IND-enabling studies. For more information, see Part I, Item 1 in this Annual Report on Form 10-K under the heading “Complement Inhibitor Programs: MASP-2 Program – Lectin Pathway Disorders”.

Alternative Pathway / MASP-3

Our pipeline of clinical-stage complement-targeted therapeutic candidates also includes zaltenibart (OMS906), a proprietary, patented monoclonal antibody targeting MASP-3, the key activator of the alternative pathway of complement. We believe zaltenibart has the potential to treat a wide range of alternative pathway-related diseases and that its attributes favorably differentiate zaltenibart from other marketed and in-development alternative pathway inhibitors.

Clinical development of zaltenibart is currently focused on PNH and C3G. We have initiated our Phase 3 clinical development program for zaltenibart in PNH and have an ongoing Phase 2 clinical trial evaluating zaltenibart in C3G. For more information, see Part I, Item 1 in this Annual Report on Form 10-K under the heading “Complement Inhibitor Programs: MASP-3 Program – Alternative Pathway Disorders”.

PDE7 Inhibitor Programs

Our 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, part of the National Institutes of Health, to develop our lead orally administered PDE7 inhibitor compound, for which we have successfully completed a Phase 1 study, for the treatment of cocaine use disorder (“CUD”). With NIDA funding, we successfully completed preclinical cocaine interaction/toxicology studies to assess safety of the OMS527 compound when co-administered with cocaine. Based on the successful outcome of the preclinical studies, we have initiated, and NIDA has confirmed availability of grant funding for, an in-patient, placebo-controlled clinical study evaluating the safety and effectiveness of OMS527 in adults with CUD who receive concurrent intravenous cocaine. For more information, see Part I, Item 1 in this Annual Report on Form 10-K under the heading “Other Clinical Programs: PDE7 Inhibitor Programs – OMS527”.

Preclinical Programs - Oncology Platform

We are developing a portfolio of signaling-driven immunomodulators, oncotoxins, and an adoptive T-cell technology combined with an immunostimulator that, unlike other cellular therapy approaches requires no cellular engineering, may reduce manufacturing costs and timelines, and may maintain an enhanced anti-cancer immune response through subsequent repetitive and simple therapeutic administrations.

Our oncology development program is operating in stealth mode as we continue to confirm our results and to generate new data which we expect will contribute to our intellectual property position. For more information, see Part I, Item 1 in this Annual Report on Form 10-K under the heading “Preclinical Programs and Platforms: Oncology Platform”.

OMIDRIA Sale and Royalty Monetization Transactions

We previously developed and commercialized OMIDRIA® (phenylephrine and ketorolac intraocular solutions) 1%/0.3%, which is approved by FDA for use during cataract surgery or intraocular lens replacement to maintain pupil size by preventing intraoperative miosis (pupil constriction) and to reduce postoperative ocular pain. We marketed OMIDRIA in the U.S. from the time of its commercial launch in 2015 until December 2021.

On December 23, 2021, we sold our commercial product, OMIDRIA, to Rayner. Rayner paid us $126.0 million at the closing and we retained all outstanding accounts receivable, accounts payable and accrued expenses as of the closing date.

As contemplated by the Asset Purchase Agreement, in December 2022, we earned a $200.0 million Milestone Payment upon the establishment of separate payment for OMIDRIA for a continuous period of at least four years when furnished in the ASC setting. We received $200.0 million in February 2023. Upon achieving the Milestone Event, the royalty rate applicable to U.S. net sales of OMIDRIA was reduced from 50% to 30%. The 30% royalty rate continues until the expiration or termination of the last issued and unexpired U.S. patent, which we expect to occur no earlier than 2035.

Upon the occurrence of certain events described in the Asset Purchase Agreement, including during any specific period in which OMIDRIA is no longer eligible for separate payment (i.e., becomes included in the packaged payment rate for the surgical procedure) under Medicare Part B, or in certain circumstances involving entry of generic competition for OMIDRIA, the U.S. base royalty rate would be further reduced to 10%. Pursuant to legislation enacted in late 2022, we expect separate payment for OMIDRIA under Medicare Part B to extend until at least January 1, 2028.

As a result of the OMIDRIA divestiture, we recorded an OMIDRIA contract royalty asset on our balance sheet. The results of OMIDRIA activities are classified as discontinued operations in our consolidated statements of operations and comprehensive income (loss) and excluded from continuing operations for all periods presented. See Part II, Item 8, “Note 7 — Discontinued Operations – Sale of OMIDRIA” to our Consolidated Financial Statements in this Annual Report on Form 10-K.

On September 30, 2022, we sold to DRI an interest in a portion of our future OMIDRIA royalty receipts for $125.0 million which we recorded as an OMIDRIA royalty obligation on our consolidated balance sheet. DRI was entitled under that arrangement to receive royalties on OMIDRIA net sales between September 1, 2022 and December 31, 2030, subject to certain annual caps.

On February 1, 2024, we sold an expanded interest in our future 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”) eliminated the previously existing annual caps on royalty payments after January 1, 2024, and provides that DRI receives all royalties on U.S. net sales of OMIDRIA payable between January 1, 2024 and December 31, 2031. In addition to the cash consideration received at closing, the Amendment also entitles us to receive two milestone payments of up to $27.5 million each, payable in January 2026 and January 2028, respectively, based on achievement of certain thresholds for U.S. net sales of OMIDRIA. 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 rights to receive all royalties payable by Rayner on any net sales of OMIDRIA outside the U.S. as well as royalties on global net sales of OMIDRIA payable from and after December 31, 2031, including royalties on U.S. OMIDRIA net sales. To date, international royalties have not been significant.  DRI has no recourse to our assets other than its interest in OMIDRIA royalties. Interest expense on the OMIDRIA royalty obligation is recorded as a component of continuing operations. See Part II, Item 8, “Note 8 – OMIDRIA Royalty Obligation” to our Consolidated Financial Statements in this Annual Report on Form 10-K for additional information.

Payment on Maturity of 2023 Notes

On November 15, 2023, we extinguished $95.0 million of our 6.25% convertible senior notes (the “2023 Notes”) at par upon maturity.

2024 Term Loan and Repurchase of 2026 Notes

In December 2023, we repurchased $9.1 million par value of our 2026 Notes on the open market at approximately 55% of par value, realizing a $4.1 million non-cash gain on extinguishment.

On June 3, 2024 (the “Closing Date”), we, with certain subsidiaries, as guarantors, entered into the Credit Agreement with Athyrium and Highbridge as lenders (together with additional lenders from time to time, the “Lenders”) and Wilmington Savings Fund Society, FSB, as administrative agent and collateral agent. The Credit Agreement provides for a senior secured term loan facility initially of up to $92.1 million consisting of (i) the Initial Term Loan of $67.1 million, which was fully funded on the Closing Date, and (ii) a $25.0 million 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. We do not expect that FDA approval of narsoplimab will be obtained within a timeframe that would permit the Delayed Draw Term Loan to be drawn absent an amendment to, or waiver of, this condition. Proceeds of the Delayed Draw Term Loan, if borrowed, must be used to fund the commercialization of narsoplimab and to pay transaction costs associated with the Delayed Draw Term Loan. The Initial Term Loan has no original issue discount, while the Delayed Draw Term Loan, if drawn, would be issued with an original issue discount of 3.00%.

In 2024, we used the $67.1 million Initial Term Loan, along with $21.7 million of cash on hand to repurchase from the Lenders $118.1 million aggregate principal amount of the 2026 Notes (the “2026 Note Repurchase Transaction”). The principal amount retired in the 2026 Note Repurchase Transaction represented a 55% reduction of the outstanding principal balance of the 2026 Notes at a purchase price of approximately 75% of par value.

We are permitted under the Credit Agreement to repurchase additional outstanding 2026 Notes for cash in open market or privately negotiated transactions, subject to certain limitations described below. Additionally, until the earlier of November 1, 2025 and the date the we elect to draw under the Delayed Draw Term Loan, we, at our sole discretion, may exchange up to $14.9 million aggregate principal amount of outstanding 2026 Notes for cash and additional term loan amounts, with the holders of such notes becoming Lenders under the Credit Agreement (any such additional term loans, together with the Initial Term Loan and the Delayed Draw Term Loan, the “Loans”). 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.

All indebtedness outstanding under the Credit Agreement is guaranteed by certain of our direct and indirect subsidiaries, other than certain foreign subsidiaries that are not material (we and the guarantors, collectively, the “Credit Parties”). Pursuant to a Pledge and Security Agreement, dated June 3, 2024, the indebtedness under the Credit Agreement is secured by a first-priority security interest in and lien on substantially all tangible and intangible property of the Credit Parties, subject to customary exceptions, and excluding royalty interests in OMIDRIA and certain related rights.

The Credit Agreement contains certain customary default provisions, representations and warranties and affirmative and negative covenants, including a covenant for the Credit Parties 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 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 we offer to prepay an equal amount of Loans with the net cash proceeds of such offering.

The Loans accrue interest at an adjusted term secured overnight financing rate, (“adjusted term SOFR”) (with a 3.00% floor) plus 8.75% per annum, payable quarterly. We may choose to pay up to 50% of any quarterly interest payment in kind by adding the portion of such interest payment to the outstanding principal amount of Loans using a quarterly interest rate of adjusted term SOFR (with a 3.00% floor) plus 10.25% per annum. A default interest rate of an additional 3.00% per annum would apply on all outstanding obligations after the occurrence and during the continuance of certain specified events of default.

The Credit Agreement with a four-year term has a scheduled maturity date of June 3, 2028 (unless all Loans become due and payable at an earlier date, whether by acceleration or otherwise). If on November 1, 2025, (i) the aggregate principal amount of the 2026 Notes outstanding that is not held by the Lenders is equal to or greater than $38.5 million and (ii) we have not made nor 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 to prepay the Loans in the amount necessary to achieve the $20.0 million prepayment requirement. We expect to prepay the $20.0 million in November 2025 along with a $1.0 million prepayment penalty and have reflected this consideration in our consolidated balance sheet. All mandatory prepayments are subject to the prepayment premiums as described below.

We may elect to prepay Loans, in whole or in part, in cash, subject to (i) during the first year of such Loans, a make-whole premium plus 5.00% of the aggregate principal amount of Loans subject to prepayment (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 5.00% prepayment premium; and (iii) during the third year, a 3.00% prepayment premium. The Credit Agreement requires mandatory prepayments of Loans in an amount equal to 60% of the net cash proceeds (excluding research and development and certain other milestone payments) received by the Credit Parties from asset sales and licenses, provided that if an asset sale or license involving narsoplimab occurs while any Delayed Draw Term Loans are outstanding, mandatory prepayments must be in an amount equal to 100% of the net cash proceeds from such sale. Mandatory prepayments are also required: (i) from insurance recoveries on loss of property that are not otherwise reinvested in other assets of the Credit Parties; (ii) from indebtedness incurred by any of the Credit Parties other than as permitted by the Credit Agreement; (iii) in the event of a change of control and (iv) in respect of 25% of the amount of any Milestone Payment received from DRI its affiliates on the basis of net sales of OMIDRIA.

Financial Summary

As of December 31, 2024, we had cash, cash equivalents and short-term investments of $90.1 million available to fund operations and to service debt.

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Results of Operations

Research and Development Expenses

Our research and development expenses can be divided into three categories: direct external expenses, which include clinical research and development and preclinical research and development activities; internal overhead and other expenses; and stock-based compensation expense. Direct external expenses consist primarily of expenses incurred pursuant to agreements with third-party manufacturing organizations prior to receiving regulatory approval for a product candidate, CROs, clinical trial sites, collaborators, licensors and consultants. Preclinical research and development includes costs prior to beginning Phase 1 studies in human subjects. Internal overhead and other expenses primarily consist of costs for personnel, overhead, rent, utilities and depreciation. Our accounting policy is to expense all manufacturing costs related to product candidates until regulatory approval is reasonably assured in either the U.S. or European Union.

The following table illustrates our expenses associated with these activities:

Clinical research and development expenses increased $0.5 million between 2024 and 2023. The change primarily relates to $16.1 million of TA-TMA drug manufacturing costs in anticipation of our BLA and $2.1 million in zaltenibart clinical trials expense and associated costs to manufacture drug supply. These costs are partially offset by a $15.5 million reduction in IgA nephropathy expenses with the closing out of the program and a $2.2 million reduction in OMS1029 expenses primarily due to the completion of one of our single ascending dose studies.

Clinical research and development expenses increased $4.8 million between 2023 and 2022. The $16.5 million increase in OMS906 development costs was due to an increase in manufacturing and Phase 2 clinical trial costs and a $5.0 million development milestone paid in 2023 under a technology license agreement. The $3.6 million increase in OMS1029 expense was primarily due to costs associated with initiation of human trials and other clinical development costs in the transition from preclinical to clinical development status in the third quarter of 2022. These increases were offset by decreased narsoplimab manufacturing costs during 2023.

Preclinical research and development expenses increased $1.3 million in 2024 compared to 2023, primarily due to increased preclinical oncology research and cocaine addiction work during 2024. The cocaine addiction work is being funded by a grant from NIDA, with associated grant revenue included in other income. The $2.1 million decrease in 2023 over 2022 in preclinical research and development expenses was primarily due to the migration of OMS1029 from preclinical to clinical research and development status during the third quarter of 2022, offset by an increase in preclinical oncology work during 2023.

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Internal overhead and other expenses increased $3.5 million for the year ended December 31, 2024 primarily due to additional employee related costs and having received an employee retention tax credit in the prior year that was recorded as an offset to expense.

The changes in stock-based compensation expense between the three covered years were due to the valuation and timing of the vesting of employee stock options.

We expect our overall research and development costs in 2025 to be slightly higher than in 2024, driven by increases in zaltenibart clinical trial costs associated with Phase 3 trials in PNH and C3G, a milestone payment under an existing licensing agreement, and drug manufacturing costs, which we expect to be partially offset by decreases in narsoplimab drug manufacturing and clinical trial costs. Our accounting policy is to expense all manufacturing costs related to product candidates until regulatory approval is reasonably assured in either the U.S. or Europe.

At this time, we are unable to estimate with certainty the longer-term costs we will incur in the continued development of our product candidates due to the inherently unpredictable nature of our preclinical and clinical development activities. Clinical development timelines, the probability of success and development costs can differ materially as new data become available and as expectations change. Our future research and development expenses will depend, in part, on the preclinical or clinical success of each product candidate as well as ongoing assessments of each program’s commercial potential. In addition, we cannot forecast with precision which product candidates, if any, may be subject to future collaborations, when such arrangements will be secured, if at all, and to what degree such arrangements would affect our development plans and capital requirements.

We are required to expend substantial resources in the development of our product candidates due to the lengthy process of completing clinical trials and seeking regulatory approval. Any failure or delay in completing clinical trials, or in obtaining regulatory approvals, could delay our generation of product revenue and increase our research and development expenses.

Selling, General and Administrative Expenses

Our selling, general and administrative expenses are comprised primarily of salaries, benefits and stock-based compensation costs for marketing and administrative personnel who are not directly engaged in research and development. Costs also include marketing expenses, professional and legal services, general corporate costs and an allocation of our occupancy costs.

The changes in stock-based compensation expense between the three covered years were due to the valuation and timing of vesting related to employee stock options.

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Our selling, general and administrative expenses are expected to be higher than in 2024. The magnitude of the anticipated increase in selling, general and administrative expenses for 2025 will be highly dependent on whether narsoplimab receives U.S. regulatory approval for treatment of TA-TMA. If narsoplimab is approved in 2025, we expect to hire a field sales force and initiate commercial launch activities which will increase our selling, general and administrative expenses.

Interest Expense

Interest expense is comprised of contractual cash and accrued interest on our 2026 Notes, 2023 Notes and Initial Term Loan.  In addition, we record pass through interest on the OMIDRIA royalty obligation, non-cash interest comprised of remeasurement adjustments taken on our OMIDRIA royalty obligation and amortization of debt discount or premiums on our notes and term debt.

Interest expense, net of premiums, discounts, issuance costs and remeasurement adjustments is shown below:

Interest expense decreased $6.2 million in 2024 compared to 2023 primarily due to extinguishing $95.0 million in par value of our 2023 Notes at maturity in November 2023 and partially repurchasing $127.2 million in collective par value of our 2026 Notes in December 2023 and June 2024 reducing interest expense on our 2026 Notes by $4.4 million. This decrease was partially offset by increased interest expense of $3.2 million related to our OMIDRIA royalty obligation as we added $115.5 million of principal upon sale in February 2024 to DRI of our remaining OMIDRIA U.S. royalty earnings through 2031.  In addition, with the execution of the Credit Agreement, we incurred $0.8 million in effective interest on our Initial Term Loan with Highbridge and Athyrium.

Interest expense increased $8.1 million in 2023 compared to 2022 primarily due to interest incurred from our OMIDRIA royalty obligation.

Contractual interest expense is comprised of cash interest paid during the year and the net change in accrued interest. Interest on our OMIDRIA royalty obligation is calculated under the effective interest method and represents a portion of the royalties remitted by Rayner to our administrative agent, Wilmington Savings Fund Society, FSB, along with principal. Pass through interest paid to DRI is offset by non-cash remeasurement adjustments taken to properly reflect the OMIDRIA royalty obligation for changes in probable cash flows on our future expected Rayner royalties.  Debt discounts on the 2026 Notes and 2023 Notes are accretive whereas the unrealized gain on the 2026 Note Repurchase Transaction is treated as a premium on the Initial Term Loan and deducted from contractual interest expense.

For further information see Part II, Item 8, “Note 6 – Debt” and “Note 8 – OMIDRIA Royalty Obligation” to our Consolidated Financial Statements in this Annual Report on Form 10-K.

Interest and Other Income

Interest and other income principally includes $8.4 million of interest earned on our investments, $1.6 million earned on sublease rental income and $1.3 million of NIDA grant income. The $5.0 million decrease in interest and other income between 2024 and 2023 was primarily due to holding lower average cash and investment balances than in the prior year. The $12.3 million increase in interest and other income between 2023 and 2022 was a result of receiving the $200.0 million Milestone Payment from Rayner in February 2023 and investing those funds.

We expect interest and other income in 2025 to be less than 2024 primarily due to lower average cash and investment balances during 2025.

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Gain on Early Extinguishment of Convertible Senior Notes

In December 2023, we repurchased $9.1 million par value of our 2026 Notes at a discount, realizing a $4.1 million non-cash gain on extinguishment.

Net Income from Discontinued Operations, Net of Tax

On December 23, 2021, we sold our commercial drug, OMIDRIA, to Rayner.  As a result of the OMIDRIA divestiture, the results of OMIDRIA operations have been classified as discontinued operations for all periods presented.

Net income from OMIDRIA discontinued operations, net of tax is shown below:

(1) For further discussion of income tax expense, please refer to Part II, Item 8, “Note 13 – Income Taxes” to our Consolidated Financial Statements in this Annual Report on Form 10-K.

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Interest on OMIDRIA contract royalty asset

During the years ended December 31, 2024, 2023 and 2022, we recorded $16.9 million, $15.3 million and $18.6 million, respectively, of income in discontinued operations representing interest income on the outstanding OMIDRIA contract royalty asset at an implied effective interest rate of 11.0%.

Remeasurement Adjustments

During the years ended December 31, 2024, 2023 and 2022, we recorded remeasurement adjustments of $8.0 million, $41.2 million and $14.5 million, respectively. Periodically, but at least annually, we remeasure the OMIDRIA contract royalty asset when there is a greater probability of achieving materially higher or lower royalty earnings than previously expected. 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. Remeasurement is impacted by any changes to the probability-weighting applied to the range of potential outcomes that could occur. For further discussion of discontinued operations, please refer to Part II, Item 8, “Note 7 – Discontinued Operations – Sale of OMIDRIA” to our Consolidated Financial Statements in this Annual Report on Form 10-K.

Milestone Income

The Milestone Event occurred in December 2022, entitling us to receive a Milestone Payment of $200.0 million from Rayner. We received the Milestone Payment together with accrued interest in February 2023.

Income Tax Expense

For the years ended December 31, 2024, 2023 and 2022, we recorded state income tax expense of $0.3 million, $0.5 million and $4.0 million, respectively, in discontinued operations.

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Financial Condition - Liquidity and Capital Resources

As of December 31, 2024, we had cash, cash equivalents and short-term investments of $90.1 million. Our cash used in operations for the year ended December 31, 2024 was $148.8 million and included a net loss for the year of $156.8 million. Pursuant to a covenant in the Credit Agreement, we must maintain $25.0 million of unrestricted cash, cash equivalents and short-term investments at all times.

In recent years, we have 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 December 31, 2024, expected repayment of a portion of the borrowings under our secured credit facility on or prior to November 1, 2025 and maturity of our 2026 Notes on February 15, 2026, raise substantial doubt about our ability to continue as a going concern through one year from the issuance of the Company's consolidated financial statements. 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. We have a sales agreement to sell shares of our common stock, from time to time, in an “at the market” equity offering facility through which we may offer and sell shares of our common stock equaling an amount up to $150.0 million. Our Delayed Draw Term Loan of $25.0 million 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; however, we do not expect that FDA approval of narsoplimab will be obtained within the timeframe that would permit us to draw the Delayed Draw Term Loan absent an amendment to, or a waiver of, this condition. Proceeds of the Delayed Draw Term Loan, if available, may only be used towards any related transaction costs and for commercialization of narsoplimab efforts of TA-TMA.

We have had preliminary discussions with certain holders of the 2026 Notes regarding a potential refinancing of the 2026 Notes and we may pursue additional debt financings to retire the 2026 Notes that remain outstanding and to raise additional capital to fund operations. Should it be necessary or determined to be strategically advantageous, we also could pursue public and private offerings of our equity securities, additional debt transactions or restructurings, 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 Initial Term Loan. See Part II, Item 8, “Note 6 – Debt” to our Consolidated Financial Statements in this Annual Report on Form 10-K for additional information.

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, potential future royalty and/or milestone receipts are excluded. Should it be necessary, we plan to manage our operating expenses and reduce our projected cash requirements by delaying clinical trials, reducing selected research and development efforts, or implementing other restructuring activities.

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Cash Flow Data

Operating Activities. Net cash used in operating activities for the year ended December 31, 2024 decreased by $223.5 million compared to the same period in 2023. This decrease was primarily due to collecting the $200.0 million Milestone Payment from Rayner in the prior year and a $15.5 million decrease in accounts payable and accrued expenses in the current year.

Net cash provided by operating activities for the year ended December 31, 2023 increased by $161.2 million compared to the same period in 2022. This increase was primarily due to collecting the $200.0 million Milestone Payment from Rayner in February 2023 and a $15.3 million increase in accounts payable and accrued expenses in 2023. This increase was partially offset by a $26.7 million change in the remeasurement of the OMIDRIA contract royalty asset, $8.7 million related to the accretion of interest on U.S. government treasury bills and a $4.1 million gain on the early extinguishment of a portion of our 2026 Notes.

Investing Activities. Net cash provided by investing activities for the year ended December 31, 2024 increased $54.8 million as compared to the same period in 2023. Significant initial investment purchases during the periods were the investment of the $200.0 million Milestone Payment we received from Rayner in February 2023 and the $115.5 million we received from DRI in February 2024 related to the sale of future OMIDRIA royalties.

Net cash provided by investing activities increased $155.0 million during 2023 compared to 2022 driven by collection of the $200.0 million Milestone Payment from Rayner we received in February 2023.

Financing Activities. Net cash provided by financing activities increased $169.0 million during 2024 compared to the prior year. The increase was primarily due to receiving $115.5 million in cash from DRI related to the sale of future OMIDRIA royalties and extinguishing $95.0 million of par value on our 2023 Notes in the prior year. This was partially offset by increased payments to DRI of $17.6 million in 2024 related to the OMIDRIA royalty obligation, an additional $16.9 million paid to repurchase our 2026 Notes and increased common stock repurchases of $7.2 million.

Net cash used in financing activities decreased $230.3 million during 2023 compared to the prior year. The decrease was primarily due to receiving $125.0 million in 2022 in connection with selling a portion of our OMIDRIA royalties to DRI and extinguishing $95.0 million of our 2023 Notes. In addition, we paid $4.9 million to retire $9.1 million par value of our 2026 Notes and repurchased $4.7 million of our common stock through a stock repurchase program in 2023.

Contractual Obligations and Commitments

Operating and Finance Leases

We have operating leases related to our office and laboratory space. The initial term of the leases is through November 2027 and we have two options to extend the lease term, each by five years. As of December 31, 2024, the remaining aggregate non-cancelable rent payable under the initial term of the lease, excluding common area maintenance and related operating expenses, was $20.2 million.

We have finance leases for certain laboratory and office equipment that have lease terms expiring through October 2029. As of December 31, 2024, the remaining aggregate non-cancellable finance lease payable was $2.2 million.

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Debt

For more information regarding the convertible senior notes extinguished in mid-November 2023, convertible senior notes due in February 2026 and our Credit Agreement, see Part II, Item 8, “Note 6 - Debt”.

OMIDRIA Royalty Obligation

For more information regarding the OMIDRIA Royalty Obligation, see Part II, Item 8, “Note 8 - OMIDRIA Royalty Obligation”.

Goods & Services

We have certain non-cancellable obligations under other agreements for the acquisitions of goods and services associated with the manufacturing of our product candidates, which contain firm commitments. As of December 31, 2024, our aggregate firm commitments were $4.7 million.

We may be required, in connection with in-licensing or asset acquisition agreements, to make certain royalty and milestone payments and we cannot, at this time, determine when or if the related milestones will be achieved or whether the events triggering the commencement of payment obligations will occur. Therefore, such payments are not included in the table above. For information regarding agreements that include these royalty and milestone payment obligations, see Part II, Item 8, “Note 10 - Commitments and Contingencies” to our Consolidated Financial Statements in this Annual Report on Form 10-K.

Critical Accounting Policies and Significant Judgments and Estimates

The preparation of our consolidated financial statements in conformity with U.S. generally accepted accounting principles (“GAAP”) requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. 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 those estimates. An accounting policy is considered critical if it is important to a company’s financial condition and results of operations and if it requires the exercise of significant judgment and the use of estimates on the part of management in its application. Although we believe that our judgments and estimates are appropriate, actual results may differ materially from our estimates. For a summary of our critical accounting policies, see Part II, Item 8, “Note 2 - Significant Accounting Policies” to our Consolidated Financial Statements in this Annual Report on Form 10-K.

We believe the following to be our critical accounting policies because they are both important to the portrayal of our financial condition and results of operations and they require critical judgment by management and estimates about matters that are uncertain:

●     OMIDRIA royalties and contract asset accounting;

●     OMIDRIA royalty obligation accounting; and

●     accounting for debt issuances, primarily related to fair valuing debt and issuance costs.

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If actual results or events differ materially from those contemplated by us in making these estimates, our reported financial condition and results of operations for future periods could be materially affected.

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. To measure the OMIDRIA contract royalty asset, we used the expected value approach which is the discounted sum of 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. Our calculations take the net present value of the sum to arrive at the OMIDRIA contract royalty asset stated on the balance sheet. We revalued the contract royalty asset to reduce the applicable royalty percentage from 50% to 30%, as required under the Asset Purchase Agreement following the occurrence of the Milestone Event triggering the $200.0 million Milestone Payment in 2022. Royalties earned will be recorded as a reduction to the OMIDRIA contract royalty asset. The amount recorded in discontinued operations in future periods will reflect interest earned on the outstanding OMIDRIA contract royalty asset and any amounts received different from the expected royalties recorded at closing. The OMIDRIA contract royalty asset is subject to changes in net sales of OMIDRIA. All else being equal, a 10% decrease or increase in net sales results in a $15.3 million change in value of the OMIDRIA contract royalty asset, resulting in a potential OMIDRIA contract royalty asset valued within the range of $138.0 million to $168.7 million. Changes in net sales could occur due to various risks such as competitors entering the market, changes in the standard of care for cataract patients and loss of separate payment status for OMIDRIA. In determining the value of the OMIDRIA contract royalty asset, we have considered all of these factors. The OMIDRIA contract royalty asset will be re-measured periodically using the expected value approach based on actual results and future expectations. Any required adjustment to the OMIDRIA contract royalty asset will be recorded in discontinued operations.

We receive monthly royalty reports of Rayner’s OMIDRIA product sales in accordance with the Asset Purchase Agreement. Upon the closing of the Asset Purchase Agreement, we determined the expected minimum net present value of future OMIDRIA royalty receipts and recognized the amount as a gain on the sale of OMIDRIA in discontinued operations on our income statement and as an OMIDRIA contract royalty asset on our balance sheet. To determine the OMIDRIA contract royalty asset, we used the expected value approach which is based on the sum of probability-weighted payments we would receive using a range of potential outcomes at an implied effective interest rate of 11%. The contract royalty asset excludes any revenue which potentially may be reversed in the event of an over estimation.

OMIDRIA Royalty Obligations

The sale of any portion of our OMIDRIA royalty receipts is treated as a liability on our consolidated balance sheet, as this does not result in the transfer of a participating interest. We amortize royalty obligation liabilities over the term of the arrangement using the effective interest method and classify interest expense as a component of continuing operations.

To the extent our estimates of future royalties are less than previous estimates, we will adjust the carrying amount of the royalty obligation to the present value of the revised estimated cash flows, discounted at the original effective interest rate utilizing the cumulative catch-up method. The adjustment would be recognized as a component of net income (loss) from continuing operations. Our estimate of cash flows from future royalties is derived from the contract royalty asset accounting described above.

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Debt Issuances

Transactions involving contemporaneous exchanges of cash between the same debtor and creditor in connection with the issuance of a new debt obligation and satisfaction of an existing debt obligation by the debtor are first evaluated as to whether they qualify as a troubled debt restructuring (“TDR”) under ASC Topic 470-60, Debt - Troubled Debt Restructuring by Debtors (“ASC 470-60”).  ASC 470-60 requires debt modifications to be evaluated if (1) the borrower is experiencing financial difficulty, and (2) the lender grants the borrower a concession.  If both conditions are met under TDR accounting, we would record as the carrying value of the new debt any repurchased old debt less any cash paid.  No gain on restructuring is recognized unless the carrying value of the new debt exceeds the undiscounted cash flows of the new debt. Any cancellation of debt income is amortized over the term of the new debt. We determined that the Initial Term Loan qualified as a TDR. Therefore, we amortized as debt premium the cancellation of debt income from the partial repurchase of the 2026 Notes against the Initial Term Loan. If a TDR is determined to not have occurred, we evaluate the modification in accordance with ASC Topic 470-50-40, Debt - Modifications and Extinguishments, which requires modification of debt instruments to be evaluated to assess whether the modifications are considered “substantial”. In instances where our future cash flows change more than 10%, we record our debt at fair value based on factors available to us for similar borrowings and use the extinguishment accounting method. We extinguished the 2023 Notes at maturity. The partial repurchase of the 2026 Notes in 2023 was deemed to be a modification whereby we were able to recognize a $4.1 million gain on debt extinguishment.

Recent Accounting Pronouncements

Please refer to Part II, Item 8, “Note 2 - Significant Accounting Policies” to our Consolidated Financial Statements in this Annual Report on Form 10-K for information regarding recent accounting pronouncements.

ITEM 7.       MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

The following discussion and analysis should be read in conjunction with the audited annual consolidated financial statements and the related notes thereto included elsewhere in this Annual Report on Form 10-K. This discussion contains forward-looking statements reflecting our current expectations that involve risks and uncertainties. Actual results may differ materially from those discussed in these forward-looking statements due to a number of factors, including those set forth in the section entitled “Risk Factors” and elsewhere in this Annual Report on Form 10-K. For further information regarding forward-looking statements, please refer to the special note regarding forward-looking statements at the beginning of this Annual Report on Form 10-K. Throughout this discussion, unless the context specifies or implies otherwise, the terms “Company,” “we,” “us” and “our” refer to Omeros Corporation and our wholly owned subsidiaries.

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Overview

We are 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 disorders including complement-mediated diseases, cancers related to the dysfunction of the immune system, and addictive and compulsive disorders.

Complement Inhibitor Programs

The complement system plays a role in the body’s inflammatory response and becomes activated as a result of tissue damage or trauma or microbial pathogen invasion. Inappropriate or uncontrolled activation of the complement system can cause diseases characterized by serious tissue injury. Three main pathways can activate the complement system: classical, lectin, and alternative. Omeros is focused on development of therapeutics to treat diseases associated with the lectin and/or alternative pathways of complement. Omeros is developing antibodies as well as small-molecule inhibitors of key enzymes known to be centrally involved in the in activation of the targeted pathway of complement.

Lectin Pathway / MASP 2

MASP-2, is a novel pro-inflammatory protein target that is the effector enzyme of the lectin pathway and is required for the function of this pathway. Omeros is developing antibodies and small-molecule inhibitors of MASP-2 as potential therapeutics for diseases in which the lectin pathway has been shown to contribute to significant tissue injury and pathology. When not treated, these diseases are typically characterized by significant end-organ damage, such as kidney or central nervous system injury. Importantly, inhibition of MASP-2 has been demonstrated not to interfere with the antibody-dependent classical complement activation pathway, a critical component of the acquired immune response to infection.

The lead drug candidate in our MASP-2 inhibitor program is narsoplimab (OMS721), a proprietary, patented human monoclonal antibody targeting MASP-2, the effector enzyme of the lectin pathway of complement. Clinical development of narsoplimab is currently focused primarily on TA-TMA and development efforts are also directed to COVID-19, ARDS and PASC. We are also developing OMS1029, a long-acting, next-generation antibody targeting MASP-2 and the lectin pathway which we expect will be well-suited to indications requiring long-term, chronic administration. In addition, we are advancing our orally administered small-molecule MASP-2 inhibitor through IND-enabling studies. For more information, see Part I, Item 1 in this Annual Report on Form 10-K under the heading “Complement Inhibitor Programs: MASP-2 Program – Lectin Pathway Disorders”.

Alternative Pathway / MASP-3

Our pipeline of clinical-stage complement-targeted therapeutic candidates also includes OMS906, a proprietary, patented monoclonal antibody targeting MASP-3, the key activator of the alternative pathway of complement. We believe OMS906 has the potential to treat a wide range of alternative pathway-related diseases and that its attributes favorably differentiate OMS906 from other marketed and in-development alternative pathway inhibitors. Clinical development of OMS906 is currently focused on rapidly advancing to Phase 3 clinical trials in multiple alternative pathway-related disorders, including PNH and C3G. We have multiple ongoing Phase 2 clinical trials evaluating OMS906 in these indications. For more information, see Part I, Item 1 in this Annual Report on Form 10-K under the heading “Complement Inhibitor Programs: MASP-3 Program – Alternative Pathway Disorders”.

PDE7 Inhibitor Programs

Our 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, part of the National Institutes of Health, to develop our lead orally administered PDE7 inhibitor compound, for which we have successfully completed a Phase 1 study, for the treatment of cocaine use disorder (“CUD”). The grant amount, a total of $6.69 million over three years, 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 study is intended to provide the toxicology data necessary to support the human study of OMS527 in CUD. The toxicology study is underway and is expected to be completed in late 2024. Additionally, with investigators at Emory University, we are also evaluating OMS527 as a potential treatment for levodopa-induced dyskinesia, a common and debilitating side effect of long-term levodopa dosing in patients with Parkinson’s disease. For more information, see Part I, Item 1 in this Annual Report on Form 10-K under the heading “Other Clinical Programs: PDE7 Inhibitor Programs – OMS527”.

Pre-clinical Programs

We are advancing preclinical research on potential molecular and cellular therapies for cancer. On the molecular front, we have developed novel biologic platforms to target cancer cells specifically and kill them directly or indirectly through the potentiation of the immune system. Our novel molecules combine tumor antigens with a potent adjuvant and show high levels of killing in cancer cells. We believe that some of these molecules could function as therapeutic vaccines against a broad range of tumors, potentially transforming treatment of both solid tumors and hematologic cancers. On the cellular front, we are evaluating novel approaches for both adoptive T cell and CAR T therapies. We have identified specific T cell signaling pathways, which, once inhibited, significantly and preferentially enhance the expansion of memory T cells that distinctively recognize and efficiently kill tumor cells. We continue to develop and validate our novel approach, which we believe could improve response rates for patients receiving either engineered or native T cell therapies for liquid or solid tumors.

OMIDRIA Sale and Royalty Monetization Transactions

We previously developed and commercialized OMIDRIA® (phenylephrine and ketorolac intraocular solutions) 1%/0.3%, which is approved by FDA for use during cataract surgery or intraocular ("IOL") replacement to maintain pupil size by preventing intraoperative miosis (pupil constriction) and to reduce postoperative ocular pain. We marketed OMIDRIA in the U.S. from the time of its commercial launch in 2015 until December 2021.

On December 23, 2021, we sold our commercial product OMIDRIA and certain related assets, including inventory and prepaid expenses, to Rayner. Rayner paid us $126.0 million in cash at the closing and we retained all outstanding accounts receivable, accounts payable, and accrued expenses as of the closing date.

Under the Asset Purchase Agreement, we were entitled to receive a $200.0 million Milestone Payment within 30 days following an event (the "Milestone Event") that establishes separate payment for OMIDRIA for a continuous period of at least four years when furnished in the ambulatory surgery center ("ASC") setting. The Milestone Event occurred in December 2022 and we recorded a $200.0 milestone receivable. We received the Milestone Payment together with accrued interest in February 2023.

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Under the Asset Purchase Agreement, the occurrence of the Milestone Event in December 2022 triggered a reduction in the U.S. royalty rate from 50% to 30% on OMIDRIA net sales until the expiration or termination of the last issued and unexpired U.S. patent, which we expect to occur no earlier than 2035. Upon the occurrence of certain events described in the Asset Purchase Agreement, including during any specific period in which OMIDRIA is no longer eligible for certain separate payment (i.e., becomes included in the packaged payment rate for the surgical procedure) under Medicare Part B, the U.S. base royalty rate would be reduced to 10%. Pursuant to legislation enacted in late 2022, we expect separate payment for OMIDRIA under Medicare Part B to extend until at least January 1, 2028.

As a result of the OMIDRIA divestiture, the results of OMIDRIA operations have been reclassified to net income from discontinued operations, net of tax in our consolidated statements of operations and comprehensive income (loss) and excluded from continuing operations for all periods presented.

On September 30, 2022, we sold to DRI an interest in a portion of our future OMIDRIA royalty receipts and received $125.0 million in cash consideration which we recorded as an OMIDRIA royalty obligation on our consolidated balance sheet. Interest expense is recorded as a component of continuing operations. The aggregate amount of royalties to which DRI is entitled under this arrangement is capped at $188.4 million.

On February 1, 2024, we sold to DRI an expanded interest in the OMIDRIA royalties pursuant to the terms of an amended and restated royalty purchase agreement dated February 1, 2024 (the “Amendment”). We received $115.5 million in cash upon closing of the Amendment. The Amendment eliminated the caps on royalty payments effective beginning in the first quarter of 2024, and provides that DRI will now receive all royalties on U.S. net sales of OMIDRIA payable between January 1, 2024 and December 31, 2031. DRI is entitled to payment only to the extent of royalty payments that are payable on U.S. net sales of OMIDRIA on or before December 31, 2031 and DRI has no recourse to our assets other than its interest in the OMIDRIA royalties. Omeros retains the right to receive all royalties payable by Rayner on any net sales of OMIDRIA outside the U.S. payable from and after January 1, 2024, as well as all royalties on global net sales of OMIDRIA payable from and after December 31, 2031. In addition to the cash consideration received at closing, the Amendment also entitles us 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 ending prior to January 1, 2026 as well as 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 ending prior to January 1, 2028. See Part II, Item 8, “Note 8 – OMIDRIA Royalty Obligation” to our Consolidated Financial Statements in this Annual Report on Form 10-K for additional information.

As of December 31, 2023, we had cash, cash equivalents and short-term investments of $171.8 million and, in February 2024, we received $115.5 million from DRI.

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Results of Operations

Research and Development Expenses

Our research and development expenses can be divided into three categories: direct external expenses, which include clinical research and development and preclinical research and development activities; internal, overhead and other expenses; and stock-based compensation expense. Direct external expenses consist primarily of expenses incurred pursuant to agreements with third-party manufacturing organizations prior to receiving regulatory approval for a drug candidate, CROs, clinical trial sites, collaborators, licensors and consultants. Pre-clinical research and development includes costs prior to beginning Phase 1 studies in human subjects. Internal, overhead and other expenses primarily consist of costs for personnel, overhead, rent, utilities and depreciation. The discontinued operations of OMIDRIA relates to the costs of drug manufacturing stability, quality control testing and costs of employees and consultants. The following table illustrates our expenses associated with these activities:

Clinical research and development expenses increased $4.8 million between 2023 and 2022. The $16.5 million increase in OMS906 development costs was due to an increase in manufacturing and Phase 2 clinical trial costs and a $5.0 million development milestone paid in 2023 under a technology license agreement. The $3.6 million increase in OMS1029 expense was primarily due to costs associated with initiation of human trials and other clinical development costs, i.e. the transition from preclinical to clinical development status in the third quarter of 2022. These increases were offset by decreased narsoplimab manufacturing costs during 2023.

The $3.5 million increase in clinical research and development costs between 2022 and 2021 was primarily due to the advancement of OMS1029 from preclinical status to clinical research and development status on initiation of the Phase 1 clinical trial in the third quarter of 2022. Additionally, we incurred increased narsoplimab drug manufacturing costs in 2022 compared to the prior year. These costs were partially offset by reduced costs in our OMS906 program resulting from the completion of toxicology study work in the second quarter of 2022.

Preclinical research and development expenses decreased $2.1 million in 2023 compared to 2022, primarily due to the migration of OMS1029 from preclinical to clinical research and development status during the third quarter of 2022, offset by an increase in preclinical oncology research costs during 2023.The $7.8 million decrease in 2022 over 2021 in preclinical research and development expenses was primarily due to the migration of OMS1029 from preclinical to clinical research and development status during the third quarter of 2022.

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The changes in stock-based compensation expense between the three covered years were due to the valuations of employee stock options.

We expect our overall research and development costs in 2024 to be similar to 2023, driven by commercial narsoplimab manufacturing costs expected to be incurred prior to FDA approval of TA-TMA, increases in OMS906 clinical and manufacturing costs, and decreases in OMS721 clinical costs. Our accounting policy is to expense all manufacturing costs related to drug candidates until regulatory approval is reasonably assured in either the U.S. or Europe.

At this time, we are unable to estimate with certainty the longer-term costs we will incur in the continued development of our drug candidates due to the inherently unpredictable nature of our preclinical and clinical development activities. Clinical development timelines, the probability of success and development costs can differ materially as new data become available and as expectations change. Our future research and development expenses will depend, in part, on the preclinical or clinical success of each drug candidate as well as ongoing assessments of each program’s commercial potential. In addition, we cannot forecast with precision which drug candidates, if any, may be subject to future collaborations, when such arrangements will be secured, if at all, and to what degree such arrangements would affect our development plans and capital requirements.

We are required to expend substantial resources in the development of our drug candidates due to the lengthy process of completing clinical trials and seeking regulatory approval. Any failure or delay in completing clinical trials, or in obtaining regulatory approvals, could delay our generation of product revenue and increase our research and development expenses.

Selling, General and Administrative Expenses

Our selling, general and administrative expenses are comprised primarily of salaries, benefits and stock-based compensation costs for sales, marketing and administrative personnel who are not directly engaged in research and development. Costs also include marketing and selling expenses, professional and legal services, general corporate costs and an allocation of our occupancy costs.

Continuing selling, general and administrative expenses, excluding stock-based compensation expense, decreased $4.1 million between 2022 and 2021 primarily related to reduced spending on pre-commercialization sales and marketing activities which were higher in 2021 as we prepared for the then anticipated approval and commercial launch of narsoplimab for the treatment of TA-TMA.

The changes in stock-based compensation expense between the three covered years were due to the valuations of employee stock options.

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Our selling, general and administrative expenses for 2024 will be highly dependent on whether narsoplimab receives U.S. marketing approval for treatment of TA-TMA. If TA-TMA is approved in 2024, we expect to hire a field sales force and initiate commercial launch activities which will increase our selling, general and administrative expenses. If narsoplimab is not approved in 2024, our selling, general and administrative expenses are expected to decrease in 2024.

Interest Expense

Interest expense is primarily comprised of interest and amortization of debt discount and issuance costs related to our convertible senior notes and interest on our DRI royalty obligation (see Part II, Item 8, "Note 6 – Convertible Senior Notes" and "Note 8 – OMIDRIA Royalty Obligation” to our Consolidated Financial Statements in this Annual Report on Form 10-K for additional information).

Interest expense increased $8.1 million in 2023 compared to 2022 primarily due to incurring interest from our DRI royalty obligation for the full year. Interest expense increased $3.0 million in 2022 compared to 2021 primarily due to interest incurred from our DRI royalty obligation only in the fourth quarter of 2022.

Interest and Other Income

The $12.3 million increase in interest and other income between 2023 and 2022 was primarily due to holding higher average cash and investment balances than in the prior year as a result of receiving a $200.0 million Milestone Payment from Rayner in February 2023. The $2.3 million increase in interest and other income between 2022 and 2021 was primarily attributable to obtaining significantly higher interest rates on our cash and investments in 2022.

We expect interest and other income in 2024 to be less than 2023 primarily due to lower average cash and investment balances during 2024.

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Gain on Early Extinguishment of Convertible Senior Notes

In December 2023, we repurchased $9.1 million par value of our 2026 Notes at a discount, realizing a $4.1 million non-cash gain on extinguishment.

Net Income from Discontinued Operations, Net of Tax

On December 23, 2021, we sold our commercial drug, OMIDRIA, to Rayner.  As a result of the OMIDRIA divestiture, the results of OMIDRIA operations have been reclassified to discontinued operations for all periods presented.

Net income from OMIDRIA discontinued operations, net of tax is shown below:

(1) For further discussion of income tax expense, please refer to Part II, Item 8, “Note 13 – Income Taxes” to our Consolidated Financial Statements in this Annual Report on Form 10-K.

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Gain on the Sale of OMIDRIA

On December 23, 2021, we completed the sale of OMIDRIA to Rayner and received $126.0 million in cash at the closing. Additionally, we recorded an OMIDRIA contract royalty asset of $184.6 million for the rights to receive future royalties from Rayner on OMIDRIA net sales. The sale of OMIDRIA qualified as an asset sale under GAAP.

Rayner’s U.S. net sales of OMIDRIA for the years ended December 31, 2023 and 2022 were $135.3 million and $130.9 million, respectively. We earned royalties of $40.6 million and $65.4 million on OMIDRIA net sales for the years ended December 31, 2023 and 2022, respectively, which we recorded as a reduction from the OMIDRIA contract royalty asset. The decrease in royalty earnings between the years ended December 31, 2023 and 2022 was due to a reduction of our royalty rate on U.S. net sales of OMIDRIA from 50% to 30% upon achievement of the $200.0 million Milestone Event. (For further discussion of discontinued operations, please refer to Part II, Item 8, “Note 7 – Discontinued Operations – Sale of OMIDRIA” to our Consolidated Financial Statements in this Annual Report on Form 10-K).

Milestone Income

The Milestone Event occurred in December 2022, entitling us to receive a Milestone Payment of $200.0 million from Rayner. We received the Milestone Payment together with accrued interest in February 2023.

Interest Income

During the years ended December 31, 2023 and 2022, we recorded $15.3 million and $18.6 million, respectively, of income in discontinued operations, representing interest income on the outstanding OMIDRIA contract royalty asset at an implied interest rate of 11.0%.

Remeasurement Adjustments

During the years ended December 31, 2023 and 2022, we recorded $41.2 million and $14.5 million, respectively, of remeasurement adjustments. The $26.7 million increase in 2023 was primarily attributable to assigning a greater probability of achieving higher royalty earnings on net sales of OMIDRIA as supported by our most recent transaction with DRI, which closed on February 1, 2024.

Income Tax Expense

For the years ended December 31, 2023, 2022 and 2021, we recorded state income tax expense of $0.5 million, $4.0 million and $1.0 million, respectively, which could not be offset by prior period net operating losses and tax credit carryforwards.

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Financial Condition - Liquidity and Capital Resources

As of December 31, 2023, we had cash, cash equivalents and short-term investments of $171.8 million.For the year ended December 31, 2023, our cash provided by operations was $74.7 million and our net loss was $117.8 million. In February 2024, we received $115.5 million upon the sale to DRI of our U.S. OMIDRIA royalty receipts payable between January 1, 2024 and December 31, 2031.

Historically, we have incurred net losses from continuing operations and negative operating cash flows. We have not yet established an ongoing source of revenue sufficient to cover our operating costs; therefore, we potentially need to continue to raise additional capital to accomplish our business plan and to retire our outstanding convertible senior notes due in 2026. We plan to continue to fund our operations for at least the next twelve months with our existing cash and investments and the $115.5 million we received in February 2024 from DRI. We have a sales agreement to sell shares of our common stock, from time to time, in an “at the market” equity offering facility through which we may offer and sell shares of our common stock equaling an aggregate amount up to $150.0 million. Should it be determined to be strategically advantageous, we could pursue debt financings as well as public and private offerings of our equity securities, similar to those we have previously completed, or other strategic transactions, which may include licensing a portion of our existing technology. Should it be necessary to manage our operating expenses, we could also reduce our projected cash requirements by delaying clinical trials, reducing selected research and development efforts, or implementing other restructuring activities.

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Cash Flow Data

Operating Activities. Net cash provided by operating activities for the year ended December 31, 2023 increased by $161.2 million compared to the same period in 2022. This increase was primarily due to collecting the $200.00 million Milestone Payment from Rayner in the current year and a $15.3 increase in accounts payable and accrued expenses. These increases were offset by a $26.7 million change in the remeasurement of the OMIDRIA contract royalty asset, $8.7 million related to the accretion of interest on U.S. government treasury bills and a $4.1 million gain on the early extinguishment of a portion of our 2026 Notes.

Net cash used in operating activities for the year ended December 31, 2022 decreased by $23.2 million compared to the same period in 2021. This change was primarily due to a decrease in net income of $146.8 million as we recognized $310.6 million of non-cash gain from the sale of OMIDRIA in the prior year and a change in cash collections of $124.7 million through accounts receivables and royalty earnings. This was offset by a $200.0 million milestone receivable recognized in 2022 as well as $35.6 million in non-cash charges and $29.7 million of accounts payable, accrued expenses and other.

Investing Activities. Net cash provided by investing activities increased $155.0 million during 2023 compared to 2022 driven by net proceeds from the purchase and sale of investments.

Net cash provided by investing activities decreased $321.3 million during 2022 compared to 2021. This was driven by a $194.5 million decrease in net proceeds from the purchase and sale of investments and recognizing $126.0 million in proceeds from the sale of OMIDRIA in 2021.

Financing Activities. Net cash used in financing activities decreased $230.3 million during 2023 compared to the prior year. The decrease was primarily due to receiving $125.0 million in 2022 in connection with selling a portion of our OMIDRIA royalties to DRI and extinguishing $95.0 million of our 6.25% convertible senior notes (the "2023 Notes"). In addition, we paid $4.9 million to retire $9.1 million par value of our 2026 Notes and repurchased $4.7 million of our common stock through a stock repurchase program in 2023.

Net cash provided by financing activities increased $117.9 million during 2022 compared to the prior year. The increase was primarily due to receiving cash proceeds of $125.0 million in connection with the sale of a portion of our OMIDRIA royalties to DRI, which was partially offset by a reduction in stock option exercises of $8.0 million during 2022.

Contractual Obligations and Commitments

Operating Leases

We lease our office and laboratory space in The Omeros Building under a lease agreement with BMR - 201 Elliott Avenue LLC. The initial term of the lease ends in November 2027 and we have two options to extend the lease term, each by five years. As of December 31, 2023, the remaining aggregate non-cancelable rent payable under the initial term of the lease, excluding common area maintenance and related operating expenses, was $26.9 million.

We have finance leases for certain laboratory and office equipment that have lease terms expiring through November 2026.

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Convertible Notes

For more information regarding the convertible senior notes extinguished in mid-November 2023 and convertible senior notes due in February 2026, see Part II, Item 8, “Note 6 - Convertible Senior Notes”.

OMIDRIA Royalty Obligation

For more information regarding the OMIDRIA Royalty Obligation, see Part II, Item 8, “Note 8 - OMIDRIA Royalty Obligation”.

Goods & Services

We have certain non-cancelable obligations under other agreements for the acquisitions of goods and services associated with the manufacturing of our drug candidates, which contain firm commitments. As of December 31, 2023, our aggregate firm commitments were $25.8 million.

We may be required, in connection with in-licensing or asset acquisition agreements, to make certain royalty and milestone payments and we cannot, at this time, determine when or if the related milestones will be achieved or whether the events triggering the commencement of payment obligations will occur. Therefore, such payments are not included in the table above. For information regarding agreements that include these royalty and milestone payment obligations, see Part II, Item 8, “Note 10 - Commitments and Contingencies” to our Consolidated Financial Statements in this Annual Report on Form 10-K.

Critical Accounting Policies and Significant Judgments and Estimates

The preparation of our consolidated financial statements in conformity with U.S. generally accepted accounting principles (“GAAP”) requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. 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 those estimates. An accounting policy is considered critical if it is important to a company’s financial condition and results of operations and if it requires the exercise of significant judgment and the use of estimates on the part of management in its application. Although we believe that our judgments and estimates are appropriate, actual results may differ materially from our estimates. For a summary of our critical accounting policies, see Part II, Item 8, “Note 2 - Significant Accounting Policies” to our Consolidated Financial Statements in this Annual Report on Form 10-K.

We believe the following to be our critical accounting policies because they are both important to the portrayal of our financial condition and results of operations and they require critical judgment by management and estimates about matters that are uncertain:

●     revenue recognition;

●     OMIDRIA royalties and contract asset accounting;

●     OMIDRIA royalty obligation accounting;

●     research and development expenses related to clinical trials;

●     accounting for convertible debt issuances, primarily related to fair valuing debt and issuance costs; and

●     stock-based compensation, primarily related to our fair value assumptions.

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If actual results or events differ materially from those contemplated by us in making these estimates, our reported financial condition and results of operations for future periods could be materially affected.

Product Revenue Recognition

Prior to the December 23, 2021 sale of OMIDRIA to Rayner, we recorded revenue from product sales when the product was delivered to our wholesalers and title for the product was transferred. Product sales were recorded net of wholesaler distribution fees and estimated chargebacks, rebates, returns and purchase-volume discounts. Accruals or allowances were established for these deductions in the same period when revenue was recognized, and actual amounts incurred were offset against the applicable accruals or allowances. We reflected each of these accruals or allowances as either a reduction in the related accounts receivable or as an accrued liability depending on how the amount was expected to be settled.

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. To measure the OMIDRIA contract royalty asset, we used the expected value approach which is the discounted sum of 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. Our calculations take the net present value of the sum to arrive at the OMIDRIA contract royalty asset stated on the balance sheet. We revalued the contract royalty asset to reduce the applicable royalty percentage from 50% to 30%, as required under the Asset Purchase Agreement following the occurrence of the December 2022 event triggering the $200.0 million Milestone Payment. Royalties earned will be recorded as a reduction to the OMIDRIA contract royalty asset. The amount recorded in discontinued operations in future periods will reflect interest earned on the outstanding OMIDRIA contract royalty asset and any amounts received different from the expected royalties recorded at closing. The OMIDRIA contract royalty asset is subject to changes in net sales of OMIDRIA. All else being equal, a 10% decrease or increase in net sales results in a $16.8 million change in value of the OMIDRIA contract royalty asset, resulting in a potential contract royalty asset valued within the range of $151.3 million to $184.9 million. Changes in net sales could occur due to various risks such as competitors entering the market, changes in the standard of care for cataract patients and loss of separate payment status for OMIDRIA. In determining the value of the OMIDRIA contract royalty asset, we have considered all of these factors. The OMIDRIA contract royalty asset will be re-measured periodically using the expected value approach based on actual results and future expectations. Any required adjustment to the OMIDRIA contract royalty asset will be recorded in discontinued operations.

We receive monthly royalty payments based on Rayner’s OMIDRIA product sales in accordance with the Asset Purchase Agreement. Upon the closing of the Asset Purchase Agreement, we determined the expected minimum net present value of future OMIDRIA royalty receipts and recognized the amount as a gain on the sale of OMIDRIA in discontinued operations on our income statement and as an OMIDRIA contract royalty asset on our balance sheet. To determine the OMIDRIA contract royalty asset, we used the expected value approach which is based on the sum of probability-weighted payments we would receive using a range of potential outcomes at an effective interest rate of 11%. The contract royalty asset excludes any revenue which potentially may be reversed in the event of an over estimation.

OMIDRIA Royalty Obligations

The sale of any portion of our OMIDRIA royalty receipts is treated as a liability on our consolidated balance sheet to the extent that any of our royalties are capped, as this does not result in the transfer of a participating interest. We amortize royalty obligation liabilities over the term of the arrangement using the effective interest method and classify interest expense as a component of continuing operations.

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To the extent our estimates of future royalties are less than previous estimates, we will adjust the carrying amount of the royalty obligation to the present value of the revised estimated cash flows, discounted at the original effective interest rate utilizing the cumulative catch-up method. The adjustment would be recognized as a component of net income (loss) from continuing operations.

Research and Development Expenses

Research and development costs are comprised primarily of:

●     contracted research and manufacturing costs;

●     clinical study costs;

●     costs of personnel, including salaries, benefits and stock compensation;

●     consulting arrangements;

●     depreciation and an allocation of our occupancy costs; and

●     other expenses incurred to sustain our overall research and development programs.

Contracted research and manufacturing costs are primarily incurred in the development and production of our drug candidates. Prior to approval, our estimates are based on the timing of services provided. We record accrued expenses equal to our estimated expense in excess of amount invoiced by the suppliers.

Clinical trial expenses are estimated on a cost per patient that varies depending on the clinical trial site. As actual costs become known to us, we adjust our estimates; these changes in estimates may result in understated or overstated expenses at any given point in time.

Convertible Debt Issuances

On January 1, 2021, we adopted Accounting Standards Update (“ASU”) 2020-06, Debt—Debt with Conversion Options (Subtopic 470.20 and Derivatives and Hedging—Contracts in Entity’s Own Equity (Subtopic 815-40) on a modified retrospective basis. ASU 2020-06 removes the separate liability and equity accounting for our convertible senior notes. As of January 1, 2021, we account for our convertible senior notes wholly as debt. Prior to January 1, 2021, we accounted for convertible debt that may be settled wholly or partially in cash upon conversion as having both a liability component (debt) and an equity component (conversion option). The cash conversion guidance applies as the embedded conversion features meet the requirements for a derivative scope exception for instruments that are both indexed to an entity’s own stock and classified in stockholders’ equity in the balance sheet. Principal cash proceeds from the instrument are allocated first to the liability component based on the fair value of non-convertible debt using the income and market-based approaches to determine an effective interest rate for present valuing the cash proceeds. For the income-based approach, we use a convertible bond pricing model that includes several assumptions such as volatility and a risk-free rate. For the market-based approach, we observe the price of derivative price instruments purchased in conjunction with our convertible senior note issuances or evaluate issuances of convertible debt securities by other companies with similar credit risk ratings at the time of issuance. The amount of the equity component is then calculated by deducting the fair value of the liability component from the principal amount of the instrument. Issuance costs from the instrument are then allocated to the liability and equity components in the same proportion as the proceeds. The equity component of the cash principal proceeds and the liability component of the issuance costs represent a debt discount.

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Transactions involving contemporaneous exchanges of cash between the same debtor and creditor in connection with the issuance of a new debt obligation and satisfaction of an existing debt obligation by the debtor are evaluated as a modification or an exchange transaction depending on whether the exchange is determined to have substantially different terms. We extinguished the 2023 Notes at maturity. The partial repurchase of the 2026 Notes was deemed to be a modification which we accounted for as a debt extinguishment.

Stock-Based Compensation

Stock-based compensation expense is recognized for all share-based payments made to employees, directors and non-employees based on estimated fair values. The fair value of our stock options is calculated using the Black-Scholes valuation model, which requires assumptions regarding volatility, risk-free rates, forfeiture rates and expected option life. We estimate forfeitures for expense recognition based on our historical experience. Groups of employees that have similar historical forfeiture behavior are considered separately. If any of the assumptions used in the Black-Scholes model change significantly, stock-based compensation expense for new awards may differ materially from that recorded for existing awards and stock-based compensation for non-employees will vary as the awards are re-measured over the vesting term.

Recent Accounting Pronouncements

Please refer to Part II, Item 8, “Note 2 - Significant Accounting Policies” to our Consolidated Financial Statements in this Annual Report on Form 10-K for information regarding recent accounting pronouncements.

ITEM 7.       MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

The following discussion and analysis should be read in conjunction with the audited annual consolidated financial statements and the related notes thereto included elsewhere in this Annual Report on Form 10-K. This discussion contains forward-looking statements reflecting our current expectations that involve risks and uncertainties. Actual results may differ materially from those discussed in these forward-looking statements due to a number of factors, including those set forth in the section entitled “Risk Factors” and elsewhere in this Annual Report on Form 10-K. For further information regarding forward-looking statements, please refer to the special note regarding forward-looking statements at the beginning of this Annual Report on Form 10-K. Throughout this discussion, unless the context specifies or implies otherwise, the terms “Company,” “we,” “us” and “our” refer to Omeros Corporation and our wholly owned subsidiaries.

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Overview

We are 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 drug candidate narsoplimab is the subject of a biologics license application (“BLA”) that, following receipt of a CRL, is pending before the the U.S. Food and Drug Administration (“FDA”) for the treatment of hematopoietic stem cell transplant-associated thrombotic microangiopathy (“HSCT-TMA”). We also have multiple Phase 3 and Phase 2 clinical-stage development programs, which are focused on complement-mediated disorders, including immunoglobulin A (“IgA”) nephropathy, atypical hemolytic uremic syndrome (“aHUS”), and COVID-19. We have successfully completed a Phase 1 clinical trial in healthy subjects and are initiating a Phase 1b clinical trial in PNH patients for our MASP-3 inhibitor OMS906 targeting the alternative pathway of complement. We also have successfully completed a Phase 1 study in our phosphodiesterase 7 (“PDE7”) program focused on addiction. In addition, we have a diverse group of preclinical programs, including GPR174, a novel target in immuno-oncology that modulates a new cancer immunity axis that we discovered. We are also advancing other related cancer therapeutics as well as CAR T-cell and adoptive T-cell therapies. Small-molecule and antibody inhibitors of GPR174 are part of our proprietary G protein-coupled receptor (“GPCR”) platform through which we control 54 GPCR drug targets and their corresponding compounds. We also possess a proprietary-asset-enabled antibody-generating technology.

On December 23, 2021, we closed on an Asset Purchase with Rayner Surgical, Inc. (“Rayner”) for the sale of our commercial product OMIDRIA and certain related assets including inventory and prepaid expenses (the “Transaction”). Rayner paid us $126.0 million in cash at closing, and we retained all outstanding accounts receivable as of the closing date. We will receive a royalty on world-wide sales of OMIDRIA and potentially a $200.0 million milestone payment if separate payment for OMIDRIA is secured in the U.S. for a continuous period of at least four years before January 1, 2025.

​

As a result of the OMIDRIA divestiture, the results of OMIDRIA operations have been reclassified to net income from discontinued operations, net of tax in our consolidated statements of operations and comprehensive loss and excluded from continuing operations for all periods presented (See Net Income from Discontinued Operations, Net of Tax below for additional information).

As of December 31, 2021, we had $157.3 million in cash and cash equivalents and short-term investments available for general corporate use and $38.2 million in accounts receivable, which we expect to collect in full by March 31, 2022.

Results of Operations

Research and Development Expenses

Our research and development expenses can be divided into three categories: direct external expenses, which include clinical research and development and preclinical research and development activities; internal, overhead and other expenses; and stock-based compensation expense. Direct external expenses consist primarily of expenses incurred pursuant to agreements with third-party manufacturing organizations prior to receiving regulatory approval for a drug candidate, contract research organizations (“CROs”), clinical trial sites, collaborators, and licensors and consultants. Costs are reported in preclinical research and development until the program enters the clinic. Internal, overhead and other expenses consist of personnel costs, overhead costs such as rent, utilities and depreciation and other miscellaneous costs. The discontinued operations of OMIDRIA relates to the costs of drug manufacturing stability and quality control testing and costs of employees and consultants. The following table illustrates our expenses associated with these activities:

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Clinical research and development expenses increased $2.3 million between 2021 and 2020 primarily due to increased narsoplimab drug manufacturing costs partially offset by reduced OMS527 toxicology study costs. The change in clinical research and development costs between 2020 and 2019 is primarily due to the migration of OMS906 from preclinical to clinical research and development beginning in the third quarter of 2020 offset by reduced MASP-2 costs.

Preclinical research and development expenses increased $4.4 million in 2021 compared to 2020, primarily due to drug substance, stability and toxicology work on OMS1029 offset by the migration of OMS906 from preclinical to clinical research and development beginning in the third quarter of 2020. The $3.6 million decrease in preclinical research and development expenses in 2020 compared to 2019 was primarily due to the advancement of OMS906 to clinical research and development in the third quarter of 2020.

The increases in internal, overhead and other expenses in all years presented are primarily due to additional employee-related costs and buildout of expanded laboratory facilities to support our research and development activities.

We expect overall continued research and development costs to increase in 2022 as we continue our ongoing Phase 3 clinical programs for narsoplimab and the manufacturing of narsoplimab drug substance to meet our clinical supply needs as well as our commercial requirements should we receive FDA approval for the use of narsoplimab for the treatment of HSCT-TMA. Our accounting policy is to expense all manufacturing costs related to drug candidates until regulatory approval is reasonably assured in either the U.S. or Europe.

At this time, we are unable to estimate with certainty the longer-term costs we will incur in the continued development of our drug candidates due to the inherently unpredictable nature of our preclinical and clinical development activities as well as the potential impact of the COVID-19 pandemic. Clinical development timelines, the probability of success and development costs can differ materially as new data become available and as expectations change. Our future research and development expenses will depend, in part, on the preclinical or clinical success of each drug candidate as well as ongoing assessments of each program’s commercial potential. In addition, we cannot forecast with precision which drug candidates, if any, may be subject to future collaborations, when such arrangements will be secured, if at all, and to what degree such arrangements would affect our development plans and capital requirements.

We are required to expend substantial resources in the development of our drug candidates due to the lengthy process of completing clinical trials and seeking regulatory approval. Any failure or delay in completing clinical trials, or in obtaining regulatory approvals, could delay our generation of product revenue and increase our research and development expenses.

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Selling, General and Administrative Expenses

Our selling, general and administrative expenses are comprised primarily of salaries, benefits and stock-compensation costs for sales, marketing and other personnel who are not directly engaged in research and development. Costs also include marketing and selling expenses, professional and legal services, general corporate costs and an allocation of our occupancy costs.

The increase in continuing selling, general and administrative expenses, excluding stock-based compensation, during both years ended December 31, 2021 and 2020 was primarily due to increased pre-commercialization activities for narsoplimab for the treatment of HSCT-TMA.

Our continuing selling, general and administrative expenses for 2022 are highly dependent on the approval of narsoplimab as we have not yet hired the narsoplimab field sales force or initiated various commercial launch activities. If narsoplimab is approved in 2022, our continuing selling, general and administrative expenses will increase as we hire the field sales team and initiate commercial launch activities. If narsoplimab is not approved, our continuing selling, general and administrative expenses are expected to be less than in 2021.

Interest Expense

Interest expense is primarily comprised of contractual interest and amortization of debt issuance and debt discount related to our 6.25% Convertible Senior Notes (the “2023 Notes”) and 5.25% Convertible Senior Notes (the “2026 Notes”) as well as interest on our finance leases. Interest expense decreased $7.1 million compared to the prior year due to the January 1, 2021 adoption of ASU 2020-06, which eliminated the amortization of the non-cash debt discount on the 2023 and 2026 Notes previously allocated to equity. This decrease was partially offset by the increase in interest related to our 2026 Notes, which were issued in August and September 2020. For more information regarding our debt and our unsecured convertible notes (see Part II, Item 8, “Note 9—Unsecured Convertible Senior Notes”).

Loss on Early Extinguishment of Debt

In August 2020, we repurchased $115.0 million of the outstanding 2023 Notes. We recorded a $13.4 million loss on early extinguishment of debt related to the unamortized discount and issuance costs related to the repurchase.

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Other Income

Other income principally includes sublease rental income and interest earned on our cash and investments. The variations between years is primarily due to $0.8 million of expenses incurred in 2020 in connection with terminating the portion of the capped call related to the 2023 Notes that we repurchased.

Income Tax Benefit

​

The income tax benefit in 2020 relates to the issuance of the 2026 Notes respectively (see Part II, Item 8, “Note 14—Income Taxes”).

In December 2019, the Financial Accounting Standards Board issued ASU 2019-12, Income Taxes (Topic 740), which is intended to simplify various aspects of the income tax accounting guidance. ASU 2019-12 eliminates the exception to the incremental approach of intra-period tax allocation when there is a loss from continuing operations and income or gain from other items. As the Company prospectively adopted ASU 2019-12 January 1, 2021, we did not apply any intraperiod allocation rules to 2021. However, we reclassified the tax benefit of income from discontinued operations in prior periods to offset losses from continuing operations.

​

During 2020, we recorded an income tax benefit of $23.3 million from continuing operations comprising $12.0 million related to the issuance of our 2026 and 2023 Notes, and an additional $11.2 million income tax benefit related to the sale of OMIDRIA assets to Rayner into income from continuing operations. During 2019, we recorded $19.7 million of income tax benefit into continuing operations related to OMIDRIA assets sold to Rayner.

Net Income from Discontinued Operations, Net of Tax

On December 23, 2021, we sold our commercial drug, OMIDRIA, to Rayner. As a result of the OMIDRIA divestiture, the results of OMIDRIA operations have been reclassified to discontinued operations in our consolidated statements of operations and comprehensive loss and excluded from continuing operations for all periods presented. Net income from discontinued operations, net of tax is as follows:

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​

Net income from OMIDRIA operations and the gain recognized on disposition of the asset is shown below:

​

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Product Sales, Net and Royalty Income

The fluctuation in 2020 product sales, net, reclassed to discontinued operations, was due to COVID-19-related reductions in the number of elective cataract procedures from mid-March 2020 through late June 2020. Additionally OMIDRIA pass-through reimbursement under Medicare Part B expired on October 1, 2020 and OMIDRIA revenues were significantly reduced. In December 2020, CMS confirmed that OMIDRIA qualifies for separate payment when used in the ASC setting, and sales normalized during the first half of 2021.

After the sale of OMIDRIA to Rayner, we receive royalty payments of 50% of U.S. domestic net sales. We will continue to earn royalties at this rate until the earlier of January 1, 2025 or when separate payment for OMIDRIA is secured in the U.S. for a continuous period of at least four years. Should separate payment be achieved during this time, the Company would receive a $200.0-million milestone payment from Rayner. Upon the earlier of qualifying for the milestone payment or January 1, 2025, the royalty rate will be reduced to 30% (the “U.S. base royalty rate”) until the expiration or termination of the last issued and unexpired U.S. patent. The U.S. base royalty rate is reduced to 10% upon the occurrence of certain events such as OMIDRIA no longer being eligible for separate payment. We will also receive a royalty of 15% on OMIDRIA net sales outside the U.S. on a country-by-country basis until the expiration or termination of the last issued and unexpired OMIDRIA patent in such country.

OMIDRIA sales have historically been highly dependent on separate payment under Medicare Part B.  Given that OMIDRIA reimbursement might be dependent on CMS’ annual renewals and policy, we would likely experience

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significant fluctuations in period-over-period OMIDRIA royalty earnings should CMS change its non-opioid separate payment policy, which likely would effect CMS’ reimbursement of OMIDRIA.

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Deductions to OMIDRIA sales consist of chargebacks, rebates, distribution fees and product return allowances (see Part II, Item 8, “Note 2—Significant Accounting Policies”).  The overall percentage deductions to OMIDRIA sales were as follows:

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​

The gain on the sale of OMIDRIA included in discontinued operations for the year ended December 31, 2021 is as follows:

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OMIDRIA Royalties and OMIDRIA Contract Royalty Assets

​

Upon the closing of the Transaction, we have rights to receive from Rayner future royalties 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 qualifies as an asset sale. To measure the OMIDRIA contract royalty asset, we used the expected value approach which is the sum of the discounted probability-weighted royalty payments, net of tax, 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 contract royalty asset excludes the achievement of the $200.0-million milestone payment and any foreign royalties to the extent it is probable that a significant reversal in the amount of cumulative income recognized will not occur. Royalties earned will be recorded as a reduction to the OMIDRIA contract royalty asset. The amount recorded in discontinued operations in future periods will reflect interest earned on the outstanding OMIDRIA contract royalty asset and any amounts received different from the expected royalties recorded at closing. The OMIDRIA contract royalty asset will also be re-measured periodically using the expected value approach based on actual results and future expectations Any required adjustment to the OMIDRIA contract royalty asset will be recorded into discontinued operations.

On December 22, 2021, the Company granted and expensed RSUs to employees who accepted offers to work for Rayner as a retention incentive to help drive sales of OMIDRIA. The RSUs vest over a two-year period contingent on continued employment at Rayner.

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Financial Condition - Liquidity and Capital Resources

As of December 31, 2021, we had $157.3 million in cash, cash equivalents and short-term investments available for general corporate use held primarily in money-market accounts, as compared to $135.0 million at December 31, 2020. As of December 31, 2021, we also had accounts receivable of $38.2 million. We have historically generated net losses and incurred negative cash flows. With the sale of OMIDRIA to Rayner, we had net income of $194.2 million and negative cash flows from operations of $109.7 million as compared to negative cash flows of $100.1 million in the prior year.

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We plan to continue to fund our operations with our cash and investments, our outstanding accounts receivable, OMIDRIA royalties and potentially the $200.0 million milestone related to achieving long-term OMIDRIA separate payment. If FDA approval is granted for narsoplimab for HSCT-TMA within the next twelve months, sales of narsoplimab will also provide funds for our operations. In addition, we have a sales agreement to sell shares of our common stock, from time to time, in an “at the market” equity offering facility through which we may offer and sell shares of our common stock having an aggregate amount of up to $150.0 million. Should it be determined to be strategically advantageous, we could pursue debt financings as well as public and private offerings of our equity securities, similar to those we have previously completed, or other strategic transactions, which may include licensing a portion of our existing technology. Should it be necessary to manage our operating expenses, we would reduce our projected cash requirements by delaying clinical trials, reducing selected research and development efforts, or implementing other restructuring activities. We have $95.0 million of 2023 Notes due in November 2023. We plan to fund the repayment of the 2023 Notes through cash from operations, including narsoplimab HSCT-TMA revenues should approval be granted by FDA, the $200.0 million milestone related to OMIDRIA, strategic transactions, sale of stock or through issuance of additional debt.

Cash Flow Data

Operating Activities. Net cash used in operating activities increased for the year ended December 31, 2021 by $9.6 million compared to the same period in 2020. The change in net income adjusted for non-cash items increased by $12.1 million. In addition, we had a $65.7 million increase in the change in operating receivables due to timing of OMIDRIA Medicare Part B reimbursement and a $34.4 million decrease in the change in accounts payable.

Net cash used in operating activities increased for the year ended December 31, 2020 by $40.0 million compared to the same period in 2019. The difference largely resulted from the $53.6 million increase in our net loss from 2019, a $33.0 million increase in cash used in accounts payable and accrued expense, and a $3.6 million increase in cash used for prepaid and other assets. These increases were partially offset by a $43.7 million increase in cash provided from collections of accounts receivable and an increase in non-cash charges of $5.6 million.

Investing Activities. Net cash provided by investing activities increased $260.7 million during 2021 compared to the same period in 2020. This was driven by the $126.0 million payment made as part of the OMIDRIA asset sale and an increase of $134.7 million in net proceeds from the purchase and sale of investments.

Net cash used in investing activities increased $63.6 million during 2020 compared to the same period in 2019, driven by an increase in purchases of investments of $133.2 million offset by proceeds from sale and maturities of investments of $66.4 million.

Financing Activities. Net cash provided by financing activities during 2021 decreased $168.2 million from the prior year. The decrease was due to receiving cash proceeds of $76.9 million, net, in the prior year, from the issuance of our 2026 Notes, which includes the payments for partial repurchase of our 2023 Notes, payments for debt issuance costs, proceeds from termination of our 2023 capped call, and purchases of capped calls related to our 2026 Notes. In addition, we received net proceeds of $93.7 million from our August 2020 public offering of our common stock.

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Convertible Notes

For more information regarding the 2023 and 2026 Notes see (Part II, Item 8, “Note 8—Unsecured Convertible Senior Notes”).

Line of Credit

We have a Line of Credit Agreement that is secured by all our assets excluding intellectual property and development program inventories and matures on August 2, 2022. The Line of Credit is based upon maintaining a certain amount of accounts receivables including royalty receivables from Rayner. As of December 31, 2021, we had no outstanding borrowings under the Line of Credit Agreement and we were in compliance with all covenants. For more information regarding the Line of Credit Agreement (see Part II, Item 8, “Note 8—Line of Credit”).

Contractual Obligations and Commitments

Operating Leases

We lease our office and laboratory space in The Omeros Building under a lease agreement with BMR - 201 Elliott Avenue LLC. The initial term of the lease ends in November 2027 and we have two options to extend the lease term, each by five years. We lease office and laboratory equipment under various operating and finance lease agreements with initial terms of five years or less. As of December 31, 2021, the remaining aggregate non-cancelable rent payable under the initial term of the lease, excluding common area maintenance and related operating expenses, is $42.9 million.

Convertible Notes

Refer to “Financial Condition—Liquidity and Capital Resources—Convertible Notes” above.

Goods & Services

We have certain non-cancelable obligations under other agreements for the acquisitions of goods and services associated with the manufacturing of our drug candidates, which contain firm commitments. As of December 31, 2021, our aggregate firm commitments are $32.0 million.

We may be required, in connection with in-licensing or asset acquisition agreements, to make certain royalty and milestone payments and we cannot, at this time, determine when or if the related milestones will be achieved or whether the events triggering the commencement of payment obligations will occur. Therefore, such payments are not included in the table above. For information regarding agreements that include these royalty and milestone payment obligations, see Part II, Item 8, “Note 11—Commitments and Contingencies” to our Consolidated Financial Statements in this Annual Report on Form 10-K.

Critical Accounting Policies and Significant Judgments and Estimates

The preparation of our consolidated financial statements, in conformity with U.S. generally accepted accounting principles (“GAAP”), requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. 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 those estimates. An accounting policy is considered critical if it is important to a company’s financial condition and results of operations and if it requires the exercise of significant judgment and the use of estimates on the part of management in its application. Although we believe that our judgments and estimates are appropriate, actual results may differ materially from our estimates. For a summary of our critical accounting policies, (see Part II, Item 8, “Note 2—Significant Accounting Policies” to our Consolidated Financial Statements in this Annual Report on Form 10-K.

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We believe the following to be our critical accounting policies because they are both important to the portrayal of our financial condition and results of operations and they require critical judgment by management and estimates about matters that are uncertain:

If actual results or events differ materially from those contemplated by us in making these estimates, our reported financial condition and results of operations for future periods could be materially affected.

Revenue Recognition

Product Sales, Net: We record revenue from product sales when the product is delivered to our wholesalers which is generally when we satisfy all performance obligations. Product sales are recorded net of wholesaler distribution fees and estimated chargebacks, rebates, returns and purchase-volume discounts. Accruals or allowances are established for these deductions in the same period when revenue is recognized, and actual amounts incurred are offset against the applicable accruals or allowances. We reflect each of these accruals or allowances as either a reduction in the related accounts receivable or as an accrued liability depending on how the amount is expected to be settled.

Chargebacks and Rebates: Provisions for chargebacks are determined utilizing historical and projected payer mix and information regarding sell-through and inventory on-hand received directly from wholesalers. Chargebacks are generally settled within four weeks of recording product sales revenue.

We provide reimbursement support services and financial assistance in the form of a rebate to patients whose commercial insurance is inadequate to cover the full cost of our drug product. We apply an experience ratio based on historical and projected patient claims. This experience ratio is applied to product sales to determine the patient rebate accrual and is reviewed and updated periodically to reflect actual results.

Distribution Fees and Product Return Allowances: We pay our wholesalers a distribution fee for services that they perform for us based on the wholesaler average cost value of their purchases. We record a provision against product sales for these charges at the time of sale to the wholesaler.

We allow for the return of product up to 12 months past its expiration date or for product that is damaged. In estimating product returns, we take into consideration our return experience to date, the remaining shelf-life of product we have previously sold, inventory in the wholesale channel and our expectation that product is typically not held by the health care providers based on the frequency of their reorders.

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OMIDRIA Royalties and OMIDRIA Contract Royalty Asset

Upon the closing of the Transaction, 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. To measure the OMIDRIA contract royalty asset, we used the expected value approach which is the the discounted sum of probability-weighted royalty payments, net of tax, 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. Our calculations take the net present value of the sum to arrive at the OMIDRIA contract royalty asset stated on the balance sheet. The contract royalty asset excludes the achievement of the $200.0- million milestone payment and any foreign royalties to the extent it is probable that a significant reversal in the amount of cumulative income recognized will not occur. Royalties earned will be recorded as a reduction to the OMIDRIA contract royalty asset. The amount recorded in discontinued operations in future periods will reflect interest earned on the outstanding OMIDRIA contract royalty asset and any amounts received different from the expected royalties recorded at closing. The OMIDRIA contract royalty asset is subject to changes in net sales of OMIDRIA. A 10% change in net sales results in an $18.4 million change in value of the OMIDRIA contract royalty asset, resulting in a potential contract royalty asset valued within the range of $166.7 million to $203.5 million, all else being equal. Changes in net sales could occur due to various risks such as competitors entering the market, technology change as to how cataracts are treated and loss of separate payment status. In determing the value of the OMIDRIA contract royalty asset, we have considered all these factors. The OMIDRIA contract royalty asset will be re-measured periodically using the expected value approach based on actual results and future expectations. Any required adjustment to the OMIDRIA contract royalty asset will be recorded into discontinued operations.

We receive monthly royalty payments based on Rayner’s OMIDRIA product sales in accordance with the Asset Purchase Agreement. Upon the closing of the Transaction, we determined the expected minimum net present value of future OMIDRIA royalty payments and recognized the amount as a gain on the sale of OMIDRIA in discontinued operations on our income statement and as OMIDRIA contract royalty asset on our balance sheet. To determine the OMIDRIA contract royalty asset, we used the expected value approach which is based on the sum of probability-weighted payments we would receive using a range of potential outcomes using a double digit discount rate and the statutory federal income tax rate. The contract royalty asset excludes any revenue which potentially may be reversed in the event of an over estimation. Therefore, we did not include any expectation of receiving the $200.0-million milestone payment or any foreign royalties as we could not judge the probability of those events with certainty.

Royalties earned will be recorded as a reduction to the OMIDRIA contract royalty asset. The amount recorded through earnings in discontinued operations will reflect the time value of money on the outstanding OMIDRIA contract royalty asset. The OMIDRIA contract royalty asset will be evaluated periodically and adjusted using the expected value approach based on actual results and future expectations. Any required adjustments will be recorded into discontinued operations.

Research and Development Expenses

Research and development costs are comprised primarily of:

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Contracted research and manufacturing costs are primarily incurred in the development and production of our drug substance and drug candidates. Prior to approval, our estimates are based on the timing of services provided. We record accrued expenses equal to our estimated expense in excess of amount invoiced by the suppliers.

Clinical trial expenses are estimated on a cost per patient that varies depending on the clinical trial site. As actual costs become known to us, we adjust our estimates; these changes in estimates may result in understated or overstated expenses at any given point in time.

Right-of-Use Assets and Related Lease Liabilities

We record operating leases on our Consolidated Balance Sheet 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 derived our incremental borrowing rate by assessing rates in recent market transactions, as adjusted for security interests and our credit quality. A change in the calculated incremental borrowing rate of 100 basis points would not be material to our consolidated financial statements.

Convertible Debt Issuances

On January 1, 2021, we adopted Accounting Standards Update (“ASU”) 2020-06, Debt—Debt with Conversion Options (Subtopic 470.20 and Derivatives and Hedging—Contracts in Entity’s Own Equity (Subtopic 815-40) on a modified retrospective basis. ASU 2020-06 removes the separate liability and equity accounting for our convertible senior notes. As of January 1, 2021, we account for our convertible senior notes wholly as debt. Prior to January 1, 2021, we accounted for convertible debt that may be settled wholly or partially in cash upon conversion as having both a liability component (debt) and an equity component (conversion option). The cash conversion guidance applies as the embedded conversion features meet the requirements for a derivative scope exception for instruments that are both indexed to an entity’s own stock and classified in stockholders’ equity in the balance sheet. Principal cash proceeds from the instrument are allocated first to the liability component based on the fair value of non-convertible debt using the income and market-based approaches to determine an effective interest rate for present valuing the cash proceeds. For the income-based approach, we use a convertible bond pricing model that includes several assumptions such as volatility and a risk-free rate. For the market-based approach, we observe the price of derivative price instruments purchased in conjunction with our convertible senior note issuances or evaluate issuances of convertible debt securities by other companies with similar credit risk ratings at the time of issuance. The amount of the equity component is then calculated by deducting the fair value of the liability component from the principal amount of the instrument. Issuance costs from the instrument are then allocated to the liability and equity components in the same proportion as the proceeds. The equity component of the cash principal proceeds and the liability component of the issuance costs represent a debt discount. which we amortized in prior years as non-cash interest expense over the term of the notes method. On

Transactions involving contemporaneous exchanges of cash between the same debtor and creditor in connection with the issuance of a new debt obligation and satisfaction of an existing debt obligation by the debtor are evaluated as a modification or an exchange transaction depending on whether the exchange is determined to have substantially different terms. The 2023 Notes repurchase and issuance of the 2026 Notes) were deemed to have substantially different terms due to the significant difference between the value of the conversion option immediately prior to and after the exchange. Therefore, the repurchase of the 2023 Notes was accounted for as a debt extinguishment.

Stock-Based Compensation

Stock-based compensation expense is recognized for all share-based payments made to employees, directors and non-employees based on estimated fair values. The fair value of our stock options is calculated using the Black-Scholes option valuation model, which requires assumptions, including volatility, forfeiture rates and expected option life. We estimate forfeitures for expense recognition based on our historical experience. Groups of employees that have similar historical forfeiture behavior are considered separately. If any of the assumptions used in the Black-Scholes model change significantly, stock-based compensation expense for new awards may differ materially from that recorded for existing awards and stock-based compensation for non-employees will vary as the awards are re-measured over the vesting term.

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Recent Accounting Pronouncements

Please refer to Part II, Item 8, “Note 2--Significant Accounting Policies” to our Consolidated Financial Statements in this Annual Report in Form 10-K for information regarding recent accounting pronouncements.