OMER Omeros Corporation

By Colin Kellaher

Shares of Omeros Corp. slid nearly 30% on Monday after the U.S. Food and Drug Administration rejected the biopharmaceutical company's application for narsoplimab to treat a frequently fatal complication of stem-cell transplantation.

The Seattle company said the FDA expressed difficulty in estimating the treatment effect of narsoplimab in hematopoietic stem cell transplant-associated thrombotic microangiopathy and asked for more information to support regulatory approval.

Omeros earlier this month had warned that the FDA had found deficiencies with its application, and that it didn't expect to resolve the issues by the agency's application target action date of Oct. 17.

Omeros on Monday said it plans to request a meeting with the FDA as soon as possible to discuss the agency's findings and determine the most expeditious path forward for approval.

Omeros shares were recently down 28.6% to $5.52 after hitting a 52-week low of $5.45 early in the session.

Write to Colin Kellaher at colin.kellaher@wsj.com

(END) Dow Jones Newswires

October 18, 2021 10:25 ET (14:25 GMT)

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