Omeros Corporation (OMER) Stock Price & How to Invest
Last updated July 2026
Short answer
Omeros (Nasdaq: OMER) is a Seattle biopharmaceutical company that spent two decades as a research story and became a commercial one in December 2025, when the FDA approved YARTEMLEA (narsoplimab-wuug) as the first and only therapy for transplant-associated thrombotic microangiopathy. Owning it means underwriting one rare-disease launch that is ramping quickly, against a balance sheet that still carries convertible debt and a shareholders' deficit.
OMER stock price
As of 2026-08-14, Omeros Corporation (OMER) last closed at $17.19, up 307.3% over the past year. Over the past 52 weeks it has traded between $4.03 and $17.35.
Prices are daily closing prices from Yahoo Finance and may be delayed. For the live quote, check your broker or Omeros Corporation's investor relations page. Walnut is informational, not investment advice.
What does Omeros Corporation (OMER) do?
Omeros Corporation develops drugs that target the complement system, the part of innate immunity that turns destructive in certain rare diseases. Its lead product, YARTEMLEA (narsoplimab-wuug), is a MASP-2 antibody approved by the FDA in December 2025 for hematopoietic stem cell transplant-associated thrombotic microangiopathy (TA-TMA) in adults and children two and older, a condition with high mortality and, until that approval, no approved treatment. Omeros also earns a royalty tail on OMIDRIA, the ophthalmic surgical drug it sold to Rayner in 2021, and in December 2025 it closed a deal handing global rights to its MASP-3 inhibitor zaltenibart (OMS906) to Novo Nordisk for $240 million in cash up front and up to $2.1 billion in total potential payments plus royalties. What remains in house is earlier stage: OMS1029, a long-acting MASP-2 antibody designed for quarterly dosing, and OMS527, a PDE7 inhibitor funded by NIDA for cocaine use disorder.
The investment picture changed twice in eight months. The Novo Nordisk transaction converted a clinical asset into cash, which Omeros has been spending on retiring its 2029 convertible notes rather than on new trials, and the YARTEMLEA launch turned a company with no product revenue into one reporting about $28.5 million of net product sales in the second quarter of 2026, up from roughly $9.9 million in the first. Second-quarter net income was about $13.2 million and operating cash flow was positive. Trailing-twelve-month revenue therefore looks tiny relative to the roughly $1.0 billion market value, but that is an artifact of a product that only started selling in January 2026; the second-quarter run rate is a far more useful denominator. The offsetting facts are that essentially all commercial revenue comes from one drug in one indication, that Europe's CHMP adopted a negative opinion on narsoplimab in June 2026 and sent the stock down about 19 percent in a day, and that several plaintiffs' firms opened investigations after that drop.
What's driving Omeros Corporation (OMER)?
1. The YARTEMLEA launch curve
TA-TMA has no approved competitor, which is unusual and is the whole reason the launch has moved this fast: gross sales went from about $11.1 million in the first quarter of 2026 to about $32.2 million in the second, with gross-to-net deductions running near 11.5 percent. The relevant question for the next few quarters is whether that reflects durable adoption at transplant centers or an initial wave of prevalent patients being treated at once. Reorder rates and the number of accounts actually dosing, rather than headline growth, are what separate the two.
2. A repaired balance sheet, not a raised one
The $240 million Novo Nordisk upfront arrived without issuing shares, and management has used the proceeds to buy back convertible debt: the 2029 notes were cut to roughly $55 million of principal by June 30, 2026, with more retired after the quarter, and a modest amount of stock was repurchased alongside. That removes future interest cost and potential dilution from a company that historically funded itself by selling equity and royalties. Cash and short-term investments stood near $132 million at the end of the quarter.
3. The OMIDRIA royalty tail and the Novo milestones
OMIDRIA still generates royalties on Rayner's US net sales through 2031, reported inside discontinued operations, and contributed about $6.6 million of net income in the second quarter. Part of that stream was previously monetized to DRI Healthcare, so the economics reaching Omeros are smaller than headline OMIDRIA sales suggest. Separately, zaltenibart milestones from Novo Nordisk are development and sales driven, which makes them real but unscheduled: they are optionality on someone else's trial timelines, not something to model as recurring.
4. Europe, label expansion and the rest of the pipeline
The CHMP negative opinion in June 2026 removed the near-term European contribution and Omeros has requested a re-examination with external expert review, an outcome that will be known later in the year. Beyond that, the in-house pipeline is thin by design after the zaltenibart sale: OMS1029 has completed Phase 1 work supporting quarterly dosing, and OMS527 is expected to begin clinical enrollment for cocaine use disorder around the end of 2026. Neither is close to contributing revenue, so pipeline value here is a call option rather than a second engine.
What are the risks to Omeros Corporation (OMER)?
Concentration is the first-order risk: one drug, one indication, one country generating essentially all product revenue, with a patient population measured in the low thousands per year. A launch that looks steep for two quarters can flatten quickly once prevalent patients are treated, and rare-disease reimbursement can widen gross-to-net deductions over time. The June 2026 CHMP negative opinion is a live setback, and re-examinations more often confirm than reverse an opinion, so European revenue should not be assumed. Several plaintiffs' firms announced investigations after the resulting share-price drop, and while no filed class action complaint was found, an investigation can turn into one. The company also still carries convertible notes and a shareholders' deficit, so a stumble in the launch would put financing back on the table for a business that has raised money on unfavorable terms before.
Is OMER a buy or a sell?
We give no verdict on Omeros Corporation. Both cases are real, which is why the question is contested at all, so here is the strongest version of each.
The case for buying. The YARTEMLEA launch curve. TA-TMA has no approved competitor, which is unusual and is the whole reason the launch has moved this fast: gross sales went from about $11.1 million in the first quarter of 2026 to about $32.2 million in the second, with gross-to-net deductions running near 11.5 percent.
The case against. Concentration is the first-order risk: one drug, one indication, one country generating essentially all product revenue, with a patient population measured in the low thousands per year.
Read the full bull and bear case on OMER, including what would have to change to break either one. Walnut is not an investment adviser.
How is Omeros Corporation (OMER) valued? (approximate, August 2026)
A simple financial snapshot. These are approximations and refresh quarterly; for current figures see Omeros Corporation's investor relations page or your broker.
- Net product revenue (Q2 2026): ~$28.5M (~$32.2M gross)
- Net product revenue (H1 2026): ~$38.4M, versus $0 a year earlier
- Net income (Q2 2026): ~$13.2M, or ~$0.18 per share
- Cash and short-term investments: ~$132M as of June 30, 2026
- 2029 convertible notes: ~$55M principal at June 30, reduced further after quarter end
- Market cap: ~$1.0B on ~72M shares outstanding
Screens that show Omeros at roughly 100 times sales are reading a trailing window that mostly predates the product: YARTEMLEA only began selling in January 2026. Against the second-quarter net revenue run rate of about $114 million annualized, the same market value is closer to nine times sales, which is an ordinary multiple for a rare-disease launch and a demanding one if the ramp stalls. Reported profitability is also flattered by one-time items, since first-half net income of about $69.3 million includes the Novo Nordisk transaction rather than recurring operations.
Who competes with Omeros Corporation (OMER)?
Complement-pathway drug developers
AstraZeneca's Alexion unit (Soliris, Ultomiris), Novartis (Fabhalta), Apellis, Regeneron and Roche all sell or develop complement inhibitors. None is approved in TA-TMA, but eculizumab has been used off label there, and these companies set the pricing, physician familiarity and clinical-development standard that any lectin-pathway drug is measured against.
Transplant and supportive-care specialists
Jazz Pharmaceuticals (Defitelio for hepatic veno-occlusive disease), Incyte (Jakafi in graft-versus-host disease), Sanofi (Rezurock) and Mesoblast (Ryoncil) sell into the same transplant centers and compete for the same budget and attention. They are the closest read on how quickly a rare post-transplant therapy can be adopted and how durable that adoption is.
Small-cap single-product launch biotechs
Investors generally price OMER against other recently commercial small caps whose value rests on one launch curve, such as Apellis, Soleno or Agios. What matters in that group is not the science but the shape of the first eight quarters of sales and whether the company reaches self-funding before its debt or cash runway forces a raise.
What stocks are similar to Omeros Corporation (OMER)?
Other names that sit close to OMER: same theme, named as a direct competitor, or held beside it in the same funds. Each entry says which. Worth a look if you are thinking about diversification within a thesis rather than concentration on one ticker.
How to invest in Omeros Corporation (OMER)
There are three common ways to get OMER exposure. Buy shares (or fractional shares) directly at any major broker. Hold an ETF that includes it, which spreads the position across many companies. Or build it into a focused thematic portfolio, so OMER sits alongside other stocks that express the same thesis.
Walnut takes the portfolio route. Describe a thesis where OMER fits (for example “AI infrastructure” or “dividend-growth large-caps”) and the AI proposes 5 to 6 constituents with target weights. You review the plan and fund it through your own broker when you're ready.
New to this? Start with how to invest in stocks, see how to analyze a stock with AI, or compare the best AI stock analyzers.
The bottom line on Omeros Corporation (OMER)
OMER has stopped being a pre-revenue biotech and become a single-product launch story, so the case now turns on how far YARTEMLEA sales run before anything else in the pipeline has to carry the company.
More on Omeros Corporation (OMER)
Whether OMER is worth buying today depends more on your time horizon and what you already hold than on any single call. We walk through valuation, what would have to go right, and the risks in is OMER a buy or a sell?, and where the stock could go from here in the OMER stock forecast.
For income investors, whether OMER pays a dividend and how the payout looks is covered in does OMER pay a dividend? And to weigh OMER against a peer, read the full side-by-side comparisons: OMER vs AZN and OMER vs NVS.
Wondering how OMER fits the portfolio you already own? Walnut is an AI investing app that connects your brokerage read-only and answers questions like that about your actual holdings: overlap, concentration, and how each position tracks the S&P 500. Compare the best AI portfolio analyzers or see the best AI investing apps in 2026.
Investing in Omeros Corporation with AI
Connect the broker you already use and ask Walnut's AI how OMER fits what you actually hold: whether you own it already through a fund, what it would do to your concentration, and how it has tracked the S&P 500. Read-only by default, and you approve anything before it reaches your broker.
FAQ
What does Omeros actually sell today?
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One approved product. YARTEMLEA (narsoplimab-wuug) was approved by the FDA on December 23, 2025 for hematopoietic stem cell transplant-associated thrombotic microangiopathy in patients two and older, and it is the first lectin-pathway inhibitor to reach the market. Omeros also collects royalties on OMIDRIA, the eye-surgery drug it sold to Rayner in 2021, which are reported inside discontinued operations rather than as product revenue.
Is Omeros still a clinical-stage biotech?
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No, not since the end of 2025. It reported about $28.5 million of net product revenue in the second quarter of 2026 and about $13.2 million of net income, with positive operating cash flow. What remains in house is early: OMS1029, a long-acting MASP-2 antibody that has finished Phase 1, and OMS527 for cocaine use disorder. So it is a commercial company with a thin pipeline rather than a pre-revenue one.
Why does OMER look like it trades at 100 times sales?
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Because the trailing-twelve-month figure on most screeners still covers quarters when the company had no product to sell. YARTEMLEA launched in January 2026, so the trailing number captures roughly two quarters of sales at most. Measured against the second-quarter run rate of about $114 million annualized, the roughly $1.0 billion market value works out closer to nine times sales. Whether that is cheap depends entirely on the launch continuing.
Why did Omeros stock drop in June 2026?
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Europe's CHMP adopted a negative opinion on the narsoplimab marketing authorization application in late June 2026, and the shares fell about 19 percent in a session, closing near $8.67. Omeros has requested a re-examination with external expert review, with the outcome expected later in 2026. The US approval and US sales were unaffected, but the decision removed the near-term European contribution from most models.
Is there a securities class action against Omeros?
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Several plaintiffs' firms, including Pomerantz, Portnoy, Bronstein and Schall, announced investigations after the June 2026 share-price drop. As of August 2026 those are investigations, not a filed complaint, and no lead-plaintiff deadline had been published. Announcements like these follow most sharp biotech declines and often go nowhere, but they can convert into a filed case, which is why the possibility belongs in the risk column rather than being ignored.
What did the Novo Nordisk deal do for Omeros?
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It converted a clinical asset into cash without issuing stock. Novo Nordisk acquired global rights to zaltenibart (OMS906), a MASP-3 inhibitor for paroxysmal nocturnal hemoglobinuria, in a transaction that closed December 1, 2025 with $240 million paid up front and up to $2.1 billion in total potential milestones plus royalties. Omeros has largely used the proceeds to retire convertible debt rather than to fund new trials.
Does Omeros pay a dividend or buy back stock?
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There is no dividend, which is normal for a company at this stage. Capital has gone toward debt reduction instead: Omeros repurchased a large slice of its 2029 convertible notes during 2026, cutting the outstanding principal to roughly $55 million by June 30 and retiring more after the quarter, alongside a modest open-market repurchase of about 489,000 shares. That removes interest cost and potential dilution rather than returning cash.
How can someone invest in OMER?
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OMER trades on the Nasdaq Global Market, so any US brokerage that offers listed equities can hold it, including brokers that support fractional share amounts. It is a single-product small cap with a recent history of 20 percent single-day moves in both directions, so position sizing tends to matter more here than entry timing. Nothing above is a recommendation to buy or sell the shares.
Walnut is informational, not investment advice. Financial figures on this page are approximations; always verify current numbers with Omeros Corporation's investor relations page or your broker before making investment decisions.