Omeros Faces Stock Drop After Negative EMA Opinion on Narsoplimab
Written by Emily J. Thompson, Senior Investment Analyst
Updated: Jun 27 2025
0mins
Omeros Corp's stock fell by 22.43% as it crossed below the 5-day SMA, following a negative opinion from the European Medicines Agency (EMA) regarding its drug narsoplimab.
The EMA's Committee for Medicinal Products for Human Use issued a negative opinion on Omeros' marketing authorization application for narsoplimab, which is intended to treat thrombotic microangiopathy (TA-TMA). This decision could significantly impact Omeros' sales and brand image in Europe, leading the company to request a re-examination of the opinion. Despite these challenges, Omeros plans to continue its global compassionate use program for Yartemlea, although supply constraints may limit access for patients in Europe.
The negative EMA opinion raises concerns about Omeros' future market prospects and could undermine investor confidence. The company is expected to face delays in the approval timeline for narsoplimab, which may affect treatment options for patients and the overall commercialization efforts in the region.
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Analyst Views on OMER
Wall Street analysts forecast OMER stock price to rise
4 Analyst Rating
3 Buy
1 Hold
0 Sell
Strong Buy
Current: 10.340
Low
36.00
Averages
43.67
High
55.00
Current: 10.340
Low
36.00
Averages
43.67
High
55.00
About OMER
Omeros Corporation is a clinical-stage biopharmaceutical company. The Company focuses on discovering, developing, and commercializing first-in-class small-molecule and protein therapeutics for both large-market and orphan indications, with a particular emphasis on complement-mediated diseases, cancers, and addictive or compulsive disorders. Its clinical-stage development programs include: narsoplimab, its antibody targeting mannan-binding lectin-associated serine protease 2 (MASP-2), the effector enzyme of the lectin pathway of complement; OMS1029, its long-acting antibody targeting MASP-2; and OMS527, its phosphodiesterase 7 (PDE7) inhibitor program. Its commercial product, YARTEMLEA, is the approved inhibitor of the lectin pathway of complement. YARTEMLEA is used for the treatment of TA-TMA in adults and in children ages two years and older. YARTEMLEA selectively inhibits MASP-2, blocking pathway activation while preserving classical and alternative complement pathway functions.
About the author
Emily J. Thompson
Emily J. Thompson, a Chartered Financial Analyst (CFA) with 12 years in investment research, graduated with honors from the Wharton School. Specializing in industrial and technology stocks, she provides in-depth analysis for Intellectia’s earnings and market brief reports.
Omeros Corporation Faces Securities Fraud Investigation
- Securities Fraud Investigation: Pomerantz LLP is investigating Omeros Corporation for potential securities fraud and other unlawful business practices, advising investors to contact them, which could lead to legal liabilities and financial repercussions for the company.
- Negative Regulatory Opinion: On June 26, 2026, Omeros announced that the CHMP of the European Medicines Agency issued a negative opinion on its marketing authorization application for narsoplimab to treat TA-TMA, impacting the product's market entry and future revenue potential.
- Significant Stock Decline: Following the negative news, Omeros's stock price fell by $2.05, or 19.12%, closing at $8.67 per share, which may undermine investor confidence and exacerbate market volatility.
- Potential Legal Consequences: The investigation by Pomerantz LLP could lead to the formation of a class action lawsuit, and if Omeros and its executives are found to have engaged in misconduct, it could have long-term implications for the company's reputation and financial health.
See More
High Options Trading Volume for Qualcomm and Replimune
- Qualcomm Options Volume: Qualcomm (QCOM) saw an options trading volume of 126,866 contracts today, representing approximately 12.7 million shares, which is about 57.5% of its average daily trading volume of 22 million shares over the past month, indicating strong market interest in its future performance.
- Bullish Call Options: Notably, the $200 strike call option expiring on June 26, 2026, has seen 6,196 contracts traded today, representing around 619,600 underlying shares, suggesting that investors are increasingly optimistic about Qualcomm's stock price appreciation.
- Replimune Options Activity: Replimune (REPL) has recorded an options trading volume of 35,327 contracts today, equivalent to approximately 3.5 million shares, which accounts for about 56.1% of its average daily trading volume of 6.3 million shares over the past month, reflecting investor confidence in its growth potential.
- Call Options Interest: Particularly, the $15 strike call option expiring on August 21, 2026, has seen a trading volume of 5,896 contracts today, representing approximately 589,600 shares, indicating a bullish sentiment among market participants regarding Replimune's stock price trajectory.
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Omeros Shares Drop 25% After EU Panel Rejects Narsoplimab Therapy
- Therapy Rejection: Omeros's transplant therapy narsoplimab was not endorsed by an expert panel of the EU drug regulator, leading to a ~25% drop in the company's shares during premarket trading.
- Negative Opinion Issued: The European Medicines Agency's Committee for Medicinal Products for Human Use adopted a negative opinion on the marketing authorization application for narsoplimab, impacting its approval process in Europe.
- Current U.S. Market Status: The therapy is already marketed in the U.S. under the brand name Yartemlea for treating thrombotic microangiopathy associated with hematopoietic stem cell transplants, indicating potential in the U.S. market.
- Future Plans: Omeros plans to request a review from an ad hoc expert group regarding the decision, with the CEO expressing confidence that Yartemlea deserves approval in Europe, and expects to achieve positive cash flow within 18 months as early uptake builds.
See More
Omeros' Yartemlea Therapy Faces EU Rejection
- Therapy Approval Denied: Omeros' Yartemlea therapy was rejected by the European Medicines Agency due to insufficient evidence of effectiveness, leading to an 18% drop in stock price, potentially reaching a seven-month low if losses persist, severely impacting commercialization efforts in the region.
- Insufficient Study Data: The EMA highlighted that the main study submitted by Omeros did not compare Yartemlea with a placebo or other treatments, and participants were on additional medications, making it impossible to ascertain the actual benefits of Yartemlea, which jeopardizes its market prospects.
- Additional Study Concerns: The regulator raised concerns about the study's conduct, including changes made during the study, effectiveness measurement methods, and dosage selection, indicating significant shortcomings in Omeros' clinical trial design that could hinder future approval processes.
- Market Sentiment Shift: Despite a 38% decline in OMER stock this year, it has tripled in value over the past 12 months, with retail sentiment shifting from 'bearish' to 'neutral' in the last 24 hours, reflecting cautious optimism about the future.
See More
Omeros Provides Update on Narsoplimab Review by EMA
- Negative CHMP Opinion: Following an oral explanation meeting with the CHMP, Omeros was informed that its marketing authorization application (MAA) for narsoplimab to treat TA-TMA received a negative opinion, which could adversely affect the company's sales and brand image in the European market.
- Request for Re-examination: Omeros intends to request a re-examination of the CHMP opinion and seek evaluation by an Ad Hoc Expert Group (AHEG) convened by the EMA, a process that may delay the approval timeline for narsoplimab in Europe and impact treatment options for patients.
- Global Compassionate Use Program: Despite regulatory challenges, Omeros plans to continue providing YARTEMLEA to TA-TMA patients under its global compassionate use program, prioritizing children; however, due to drug supply constraints, only a fraction of patients in Europe may receive treatment, potentially leading to avoidable deaths.
- Clinical Data Support: The MAA is backed by clinical data from Omeros' pivotal trial of narsoplimab in TA-TMA, demonstrating its efficacy and safety, but the negative CHMP opinion may undermine future clinical research and market confidence.
See More
Investment Comparison Between NovoCure and Omeros
- NovoCure's Market Performance: NovoCure reported nearly $655.4 million in FY 2025 revenue, an 8.3% increase year-over-year, despite facing a net loss of approximately $136.2 million, indicating high costs associated with market expansion.
- Omeros's Product Launch: Omeros received FDA approval for Yartemlea in late 2025, with first-quarter sales reaching $9.89 million, reflecting strong market interest, and is projected to generate $68 million in revenue for 2026, showcasing its potential for commercial transition.
- Risk Analysis: NovoCure's heavy reliance on Optune Gio for revenue poses risks if it fails to expand into new markets or faces changes in Medicare policies, while Omeros's success hinges on the market acceptance of Yartemlea and its dependence on Novo Nordisk for development.
- Valuation Comparison: NovoCure appears significantly cheaper with a P/S ratio of 2.4 compared to Omeros's 74.3, indicating a higher market valuation for Omeros despite profitability not being expected until 2028 and beyond.
See More
Omeros Corporation Faces Securities Fraud Investigation
- Securities Fraud Investigation: Pomerantz LLP is investigating Omeros Corporation for potential securities fraud and other unlawful business practices, advising investors to contact them, which could lead to legal liabilities and financial repercussions for the company.
- Negative Regulatory Opinion: On June 26, 2026, Omeros announced that the CHMP of the European Medicines Agency issued a negative opinion on its marketing authorization application for narsoplimab to treat TA-TMA, impacting the product's market entry and future revenue potential.
- Significant Stock Decline: Following the negative news, Omeros's stock price fell by $2.05, or 19.12%, closing at $8.67 per share, which may undermine investor confidence and exacerbate market volatility.
- Potential Legal Consequences: The investigation by Pomerantz LLP could lead to the formation of a class action lawsuit, and if Omeros and its executives are found to have engaged in misconduct, it could have long-term implications for the company's reputation and financial health.
See More
High Options Trading Volume for Qualcomm and Replimune
- Qualcomm Options Volume: Qualcomm (QCOM) saw an options trading volume of 126,866 contracts today, representing approximately 12.7 million shares, which is about 57.5% of its average daily trading volume of 22 million shares over the past month, indicating strong market interest in its future performance.
- Bullish Call Options: Notably, the $200 strike call option expiring on June 26, 2026, has seen 6,196 contracts traded today, representing around 619,600 underlying shares, suggesting that investors are increasingly optimistic about Qualcomm's stock price appreciation.
- Replimune Options Activity: Replimune (REPL) has recorded an options trading volume of 35,327 contracts today, equivalent to approximately 3.5 million shares, which accounts for about 56.1% of its average daily trading volume of 6.3 million shares over the past month, reflecting investor confidence in its growth potential.
- Call Options Interest: Particularly, the $15 strike call option expiring on August 21, 2026, has seen a trading volume of 5,896 contracts today, representing approximately 589,600 shares, indicating a bullish sentiment among market participants regarding Replimune's stock price trajectory.
See More
Omeros Shares Drop 25% After EU Panel Rejects Narsoplimab Therapy
- Therapy Rejection: Omeros's transplant therapy narsoplimab was not endorsed by an expert panel of the EU drug regulator, leading to a ~25% drop in the company's shares during premarket trading.
- Negative Opinion Issued: The European Medicines Agency's Committee for Medicinal Products for Human Use adopted a negative opinion on the marketing authorization application for narsoplimab, impacting its approval process in Europe.
- Current U.S. Market Status: The therapy is already marketed in the U.S. under the brand name Yartemlea for treating thrombotic microangiopathy associated with hematopoietic stem cell transplants, indicating potential in the U.S. market.
- Future Plans: Omeros plans to request a review from an ad hoc expert group regarding the decision, with the CEO expressing confidence that Yartemlea deserves approval in Europe, and expects to achieve positive cash flow within 18 months as early uptake builds.
See More
Omeros' Yartemlea Therapy Faces EU Rejection
- Therapy Approval Denied: Omeros' Yartemlea therapy was rejected by the European Medicines Agency due to insufficient evidence of effectiveness, leading to an 18% drop in stock price, potentially reaching a seven-month low if losses persist, severely impacting commercialization efforts in the region.
- Insufficient Study Data: The EMA highlighted that the main study submitted by Omeros did not compare Yartemlea with a placebo or other treatments, and participants were on additional medications, making it impossible to ascertain the actual benefits of Yartemlea, which jeopardizes its market prospects.
- Additional Study Concerns: The regulator raised concerns about the study's conduct, including changes made during the study, effectiveness measurement methods, and dosage selection, indicating significant shortcomings in Omeros' clinical trial design that could hinder future approval processes.
- Market Sentiment Shift: Despite a 38% decline in OMER stock this year, it has tripled in value over the past 12 months, with retail sentiment shifting from 'bearish' to 'neutral' in the last 24 hours, reflecting cautious optimism about the future.
See More
Omeros Provides Update on Narsoplimab Review by EMA
- Negative CHMP Opinion: Following an oral explanation meeting with the CHMP, Omeros was informed that its marketing authorization application (MAA) for narsoplimab to treat TA-TMA received a negative opinion, which could adversely affect the company's sales and brand image in the European market.
- Request for Re-examination: Omeros intends to request a re-examination of the CHMP opinion and seek evaluation by an Ad Hoc Expert Group (AHEG) convened by the EMA, a process that may delay the approval timeline for narsoplimab in Europe and impact treatment options for patients.
- Global Compassionate Use Program: Despite regulatory challenges, Omeros plans to continue providing YARTEMLEA to TA-TMA patients under its global compassionate use program, prioritizing children; however, due to drug supply constraints, only a fraction of patients in Europe may receive treatment, potentially leading to avoidable deaths.
- Clinical Data Support: The MAA is backed by clinical data from Omeros' pivotal trial of narsoplimab in TA-TMA, demonstrating its efficacy and safety, but the negative CHMP opinion may undermine future clinical research and market confidence.
See More
Investment Comparison Between NovoCure and Omeros
- NovoCure's Market Performance: NovoCure reported nearly $655.4 million in FY 2025 revenue, an 8.3% increase year-over-year, despite facing a net loss of approximately $136.2 million, indicating high costs associated with market expansion.
- Omeros's Product Launch: Omeros received FDA approval for Yartemlea in late 2025, with first-quarter sales reaching $9.89 million, reflecting strong market interest, and is projected to generate $68 million in revenue for 2026, showcasing its potential for commercial transition.
- Risk Analysis: NovoCure's heavy reliance on Optune Gio for revenue poses risks if it fails to expand into new markets or faces changes in Medicare policies, while Omeros's success hinges on the market acceptance of Yartemlea and its dependence on Novo Nordisk for development.
- Valuation Comparison: NovoCure appears significantly cheaper with a P/S ratio of 2.4 compared to Omeros's 74.3, indicating a higher market valuation for Omeros despite profitability not being expected until 2028 and beyond.
See More
