Omeros Corporation (OMER) jumped 81.14%, closing at $15.85, up $7.10, after the U.S. FDA approved Yartemlea (narsoplimab-wuug) for the treatment of transplant-associated thrombotic microangiopathy (TA-TMA), a serious complication of stem cell transplants.
The stock opened near $12.10, reached an intraday high of around $16.50, and saw a low of nearly $11.95, compared to its previous close of $8.75. OMER trades on the NasdaqGS.
The FDA decision makes Yartemlea the first and only approved therapy for TA-TMA in adults and children aged two years and older. The drug, which selectively inhibits the MASP-2 enzyme involved in the lectin pathway of complement, offers a new treatment option for a rare, often fatal condition with limited prior therapy options. The approval follows clinical data showing meaningful survival improvements in patients treated with the therapy.
Trading volume was reflecting strong investor interest following the regulatory milestone. OMER's 52-week range recently spanned lower levels, with the sharp rally driven by expanded commercial prospects tied to Yartemlea's approval and anticipated market launch in early 2026.
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