This section highlights FDA-related milestones and regulatory updates for drugs developed by Omeros (OMER).
Over the past two years, Omeros has reported clinical trial outcomes, regulatory submissions, approvals, and other FDA events for drugs and therapies such as
Narsoplimab and OMS906. For definitions of regulatory abbreviations such as NDA, BLA, or PDUFA, see the event status legend.
Select a button below to view the list of FDA events for that drug.
Narsoplimab FDA Regulatory Timeline and Events
Narsoplimab is a drug developed by Omeros for the following indication: Hematopoietic stem cell transplant-associated thrombotic microangiopathy (HSCT-TMA).
This drug is under review by the U.S. Food and Drug Administration (FDA).
Below is a timeline of key regulatory milestones for this therapy.
- Drug:
- Narsoplimab
- Announced Date:
- May 6, 2025
- Indication:
- Hematopoietic stem cell transplant-associated thrombotic microangiopathy (HSCT-TMA)
Announcement
Omeros Corporation announced that the U.S. Food and Drug Administration (FDA) has accepted for review the resubmission of the Biologics License Application (BLA) for narsoplimab for the treatment of hematopoietic stem cell transplant-associated thrombotic microangiopathy (TA-TMA).
AI Summary
Omeros Corporation announced that the U.S. Food and Drug Administration (FDA) has accepted for review the resubmission of its Biologics License Application (BLA) for narsoplimab, aimed at treating hematopoietic stem cell transplant-associated thrombotic microangiopathy (TA-TMA). The resubmission is classified as a Class 2 application under the Prescription Drug User Fee Act and carries a target action date in late September 2025.
The submission includes key analyses comparing overall survival rates between narsoplimab-treated patients and an external control group, with the results showing statistically significant and clinically meaningful survival improvements. It also features survival data from Omeros’ expanded access program involving both adult and pediatric TA-TMA patients. Omeros is actively engaging with the FDA during this interactive review period while preparing a European marketing authorization application for narsoplimab later this quarter.
Read Announcement- Drug:
- Narsoplimab
- Announced Date:
- February 20, 2025
- Indication:
- Hematopoietic stem cell transplant-associated thrombotic microangiopathy (HSCT-TMA)
Announcement
Omeros Corporation announced statistical analysis results related to the expanded access program (EAP) for narsoplimab, Omeros' first-in-class monoclonal antibody inhibiting the lectin pathway of complement, in the treatment of hematopoietic stem cell transplant-associated thrombotic microangiopathy (TA-TMA), a life-threatening complication in both adult and pediatric hematopoietic stem cell transplantation (HSCT).
AI Summary
Omeros Corporation announced positive statistical analysis results from its expanded access program (EAP) evaluating narsoplimab for treating hematopoietic stem cell transplant-associated thrombotic microangiopathy (TA-TMA). The independent analyses showed that narsoplimab, a first-in-class monoclonal antibody inhibiting the lectin pathway of complement, produced a marked survival advantage. Combined data from both the EAP and pivotal trials indicated that narsoplimab reduced the risk of mortality between 2- and 3-fold compared to external control patients, with hazard ratios ranging from 0.34 to 0.46 and p-values less than 0.00002. These findings were consistent in rigorous statistical models and applied to both adult and pediatric patients, including those who had previously failed other treatments. The robust survival benefit supports the clinical value of narsoplimab in this life-threatening condition and is a key part of Omeros’ upcoming regulatory resubmissions.
Read Announcement- Drug:
- Narsoplimab
- Announced Date:
- February 10, 2025
- Indication:
- Hematopoietic stem cell transplant-associated thrombotic microangiopathy (HSCT-TMA)
Announcement
Omeros Corporation announced two presentations that will be featured at the 2025 Tandem Meetings – the Transplantation & Cellular Therapy Meetings of the American Society for Transplantation and Cellular Therapy and the Center for International Blood and Marrow Transplant Research, to be held February 12-15, 2025 in Honolulu, Hawaii.
AI Summary
Omeros Corporation announced that it will feature two important presentations at the 2025 Tandem Meetings in Honolulu, Hawaii, taking place from February 12-15, 2025. These presentations will be part of the Transplantation & Cellular Therapy Meetings hosted by the American Society for Transplantation and Cellular Therapy and the Center for International Blood and Marrow Transplant Research.
The presentations highlight real-world outcomes from hematopoietic stem cell transplant patients with transplant-associated thrombotic microangiopathy (TA-TMA) who were treated with narsoplimab through an expanded access program. One presentation, delivered by Dr. Michelle Schoettler from Emory University, focuses on overall survival in 128 patients, while the second, presented by Dr. Piyatida Chumnumsiriwath of the University of California, Irvine, covers outcomes in adult patients who did not respond to eculizumab treatment.
Read Announcement- Drug:
- Narsoplimab
- Announced Date:
- January 16, 2025
- Indication:
- Hematopoietic stem cell transplant-associated thrombotic microangiopathy (HSCT-TMA)
Announcement
Omeros Corporation announced statistical sensitivity analysis results related to the primary endpoint analysis for narsoplimab, Omeros' first-in-class monoclonal antibody inhibiting the lectin pathway of complement, in the treatment of hematopoietic stem cell transplant-associated thrombotic microangiopathy (TA-TMA), a life-threatening complication in both adult and pediatric hematopoietic stem cell transplantation.
AI Summary
Omeros Corporation announced new sensitivity analysis results for narsoplimab, its first-in-class monoclonal antibody targeting the lectin pathway of complement, in the treatment of hematopoietic stem cell transplant-associated thrombotic microangiopathy (TA-TMA). An independent statistical group conducted the analyses, which confirmed the strength and consistency of the primary endpoint findings. Narsoplimab-treated patients showed a significant reduction in the risk of mortality, with hazard ratios ranging from 0.24 to 0.42 and p-values as low as < 0.00001. These results reinforce the previous finding of a more than threefold decrease in mortality risk compared to an external control group of TA-TMA patients.
Omeros now plans to resubmit its biologics license application to the FDA later this quarter, aiming for approval of narsoplimab as the first therapy for TA-TMA.
Read Announcement
OMS906 FDA Regulatory Events
OMS906 is a drug developed by Omeros for the following indication: Paroxysmal Nocturnal Hemoglobinuria.
This drug is under review by the U.S. Food and Drug Administration (FDA).
Below is a timeline of key regulatory milestones for this therapy.
- Drug:
- OMS906
- Announced Date:
- March 21, 2025
- Indication:
- Paroxysmal Nocturnal Hemoglobinuria
Announcement
Omeros Corporation today reported that clinical trial site activation for enrollment is underway for the company's Phase 3 program evaluating zaltenibart in paroxysmal nocturnal hemoglobinuria (PNH).
AI Summary
Omeros Corporation has started activating clinical trial sites for enrolling patients in its Phase 3 program to evaluate zaltenibart for paroxysmal nocturnal hemoglobinuria (PNH). The clinical study will take place at approximately 120 investigational sites in 30 different countries, with many sites already having pools of eligible PNH patients. Zaltenibart is an investigational drug that works by inhibiting MASP-3, a key protein in the alternative pathway of the complement system. This treatment targets both intravascular and extravascular hemolysis and is given intravenously every eight weeks, offering a potential benefit over current treatments that require more frequent dosing.
The trial is a critical step in gathering data for the future biologics license application, with the program expected to be completed in time to support submission in the fourth quarter of 2026.
Read Announcement
Free OMER Stock Alerts