UPDATE 1-Vanda releases efficacy data for schizophrenia drug

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LOS ANGELES, Dec 12 (Reuters) - Vanda Pharmaceuticals Inc (VNDA.O: Quote, Profile, Research, Stock Buzz) said on Wednesday that data from four late-stage clinical trials showed that its experimental antipsychotic, iloperidone, produced significantly greater improvements in schizophrenia symptoms compared with a placebo.

Vanda also said iloperidone has a favorable safety and tolerability profile.

The Rockville, Maryland-based company included results from the studies in its Nov. 26 application for approval from the U.S. Food and Drug Administration.

Shares in Vanda closed up 22 cents, or 2.55 percent, at $8.85 on the Nasdaq, but then slipped 2 percent to $8.67 as investors digested the company's after-hours announcement. (Reporting by Lisa Baertlein, editing by Gary Hill)