** Shares of biopharma firm Neuren Pharmaceuticals NEU.AX tumble as much as 22.1% to A$12.660, posting their biggest intraday pct loss since early August 2018

** Stock is the top drag on the ASX 200 .AXJO, which is up 1.3%

** NEU says licensee Acadia Pharmaceuticals ACAD.O has reported that a committee of the European Medicines Agency issued a negative trend vote on its marketing-authorisation application for the trofinetide drug

** Adds, depending on the outcome of the committee's vote in February, ACAD plans to request a re-examination of the opinion once it is formally adopted

** Trofinetide is a medication used to treat Rett syndrome

** Shares heading for their eighth straight session of losses

** Over 459,500 shares change hands, 1.5x the 30-day avg

** Stock down 20.9% YTD

(Reporting by Kumar Tanishk in Bengaluru)

((Tanishk.Kumar@thomsonreuters.com; X: @thatstanishk http://www.x.com/thatstanishk;))