Narsoplimab faces a critical PDUFA date on December 26, 2025, with an EMA decision expected mid-2026. The initial indication is transplant-associated thrombotic microangiopathy (TA-TMA), a rare and often fatal complication after stem cell transplant. TA-TMA is marked by small-vessel damage, clot formation, organ injury, and multi-organ failure. Mortality rates are high and there are no approved therapies.
The FDA previously issued a Complete Response Letter (CRL) due to challenges in interpreting efficacy. Since then, Omeros has worked closely with the agency on protocol, statistical methodology, and external control analyses. The FDA extended the review to December 2025 to evaluate the new data. Omeros noted that “all analyses requested by FDA as part of its review have been consistent with and have provided statistically significant support” for narsoplimab’s benefit (Q2 2025 Results). Narsoplimab carries Orphan Drug Designation in both the U.S. and EU, with patents running to 2038.
Financial Setup
In June 2025, Omeros raised cash through a modest dilution, providing runway to the PDUFA date. This sets up a binary outcome:
- Another CRL → likely sharp downside.
- Approval → major upside, as market cap is very low versus commercial potential.
Management
- Gregory A. Demopulos, M.D., founder & CEO, has led Omeros for 30+ years and is inventor on dozens of patents.
- Nadia Dac, CCO, brings 30+ years in pharma and led key launches at AbbVie.
Together they provide scientific vision and commercial execution.
Commercial Outlook
Omeros owns 100% of global sales rights to narsoplimab. With no approved standard therapy, exclusivity is highly valuable. Analysts see > $1B peak sales potential, backed by strong efficacy data and orphan status. Approval could drive rapid adoption in transplant centers and establish narsoplimab as a cornerstone therapy.
My Position
I hold a small position. This is a pure PDUFA play. Another CRL would likely crush the stock, but approval could deliver major upside given the low valuation and blockbuster potential in an area of urgent unmet need.