UPDATE 1-Glaxo seeks U.S. approval for anti-nausea drug

(Adds further details, shares)

LONDON, May 29 (Reuters) - GlaxoSmithKline Plc (GSK.L: Quote, Profile, Research) said on Thursday it had submitted its new anti-nausea drug Rezonic for approval in the United States, and presented fresh clinical data supporting the medicine's effectiveness.

Rezonic, which also has the alternative trademark Zunrisa and is known generically as casopitant, is designed to relieve chemotherapy-induced nausea and vomiting. Analysts believe it could eventually generate sales of around $1.5 billion a year.

New clinical data from two Phase III trials demonstrated complete response rates of 86 percent for patients given a single dose of Rezonic, together with the standard dual therapy of Zofran -- an old off-patent Glaxo drug -- and dexamethasone.

Shares in Glaxo were 0.5 percent lower at 11.12 pounds by 1230 GMT, underperforming the European drugs sector , which advanced 0.7 percent. The stock was hit by worries about prospects for another new drug, Promacta, following negative comments from a U.S. Food and Drug Administration reviewer. [ID:nN28424106] (Reporting by Ben Hirschler; Editing by Quentin Bryar)